Are power outlets in a home out of phase with each other? I'm working on a science project and there's one aspect of home wiring I need to find out (don't worry, I'm not messing with wiring - this is all on paper).  Since 120V outlets in a home can be wired to either of the two 120V legs that come in from the power company, would it be a true statement that outlets on different breakers could be out of phase with each other?  In other words if Bedroom 1 is tied to leg 1 and bedroom 2 is tied to leg 2 is it reasonable to assume that the sine waves measured from outlets in bedroom 1 will be out of phase with the sine waves measured from outlets in bedroom 2?

Sort of. It depends on your frame of reference.

If you're looking at the ungrounded (hot) conductor from each receptacle, you'll end up with a 240 volt circuit.  Since it's a single circuit, it can't be out of phase with itself. If you hooked up an oscilloscope to the ungrounded (hot) conductor of each receptacle, you'd get a single 240 volt sine wave.

If you're looking at the two separate circuits (e.g. the ungrounded (hot) and grounded (neutral) conductor from each receptacle), then you'll end up with two 120 volt circuits 180° phase shifted from each other. If you hooked up the oscilloscope to the ungrounded (hot) conductor and grounded (neutral) conductors from each receptacle (4 leads instead of 2), you'd see two 120 volt sine waves 180° phase shifted from each other.

The two sine waves should look something like this.

Because the waves are phase shifted 180°, the electrical potential between the legs (at the peak) will be 240 volts. While the potential between either line and "neutral", will be 120 volts.

If the waves were not phase shifted, they'd be at the same potential (or have 0 volts between them).

So while this is not a multi phase system, it's also not a simple single phase system.  Technically it's known as a "Single split phase system".

All of this; of course, assumes that the ungrounded (hot) conductors are from different legs of the service.


Didn't stain my new fence this summer: do it while its cold or wait until next year? I have a new fence built from pressure-treated wood.  We did not get around to staining it this fall and the temperatures are now in the 40s.  Is it better just to wait until next year or should I attempt to stain it anyway?  Which is the better of two less than ideal options?

I live in SW Pennsylvania with wet winters and humid summers, so the fence will be experiencing a lot of varied weather until conditions are good for doing the job properly.  Its possible that we'll get a week back up in the high 40 or low 50s before Christmas, and I can take time off whenever to get the job done.

Definitely wait.  The temperature will be dropping low enough during the stain's curing process that many problems could present themselves.

GOOD NEWS, HOWEVER!  If you used pressure treated lumber, then staining the wood is almost entirely an aesthetic decision.  While lack of a stain will cause a greying of the wood over several years of UV exposure, the wood beneath the grey will remain sturdy.  (Also even with the stain, eventually UV will take its toll.)

Rest easy - it's a non-issue.

When it comes time to stain, http://www.sherwin-williams.com/homeowners/ask-sherwin-williams/staining/exterior-stains/  should give you all the prep info you'll need.


We're in the middle of a(n epic) flood. Why won't my toilet flush? Apologies if this isn't exactly on topic, but I found Why will my toilet not flush after it rains or when ground is wet here, and my question is similar, so hopefully I can get a response.

I live in an area very susceptible to floods, and we're in the middle of the results of Harvey.  To be clear, that means cataclysmic flooding throughout the city.  Bayous are overflowing, and it's likely that all of the city sewers are as overrun as they can be, and may be backing up.

I know nothing about plumbing (though I know that we use the municipal system, not a septic), and we currently still have running water.  All of the sinks seem fine - water comes out of the faucet and down the drain.  But when we flush our toilet, the bowl fills up somewhat and slowly drains down.  The tank refills properly.  This happened first with one toilet (which, if it matters, is closer to the sewage line), and eventually has happened with the other toilet.  We've had the exact same behavior with the other massive floods over the past few years.

My interpretation is that the city sewage line is sufficiently backed up that what we flush sits in our pipes connecting to the sewage line, and once our pipes fill up, can't go any further.

What does this mean to us?  Obviously, try to limit our use of the toilets until the city sewer system recovers.  But I don't know enough about what lines go where.  Is it safe to run the sink?  Can I still wash dishes?  There's no great need for it, but could I use the washing machine?  I'd assume all lines would back up equally over time, but I know there are differences between sewer lines and whatever the other lines are called that go out of our house.

Are there any recommendations for being able to use the toilet?  "Hold it in until it's over" doesn't work when this flooding may go on for literally a week.

I've also looked at Toilet not flushing after flooding, but the consistent behavior during floods and only during floods seems to imply that our line hasn't collapsed.

Scott,
I'm not a plumber but I think I have been through just about anything plumbing issues can throw at you. I think you provided enough information to get it figured out. I don't think it's item one below since you said it's only an issue when you have torrential rainfall. BUT. One comment made me address this too.

When you said the toilet fills up somewhat when flushed, it leads me to believe your tank is not filling up and getting enough water for a complete flush. - Pull the lid off the back of the toilet and make sure it's filled up before you flush. (should be a water mark / stain showing where the normal level is) If it's not full, it won't flush properly. Get some water from another faucet and fill the tank up and flush. If that works. Good. If not, you have another issue.
Since you are in a municipality (mud district), your house and the neighbor directly behind you are piped into the main sewer line. (All lines run out the back at connect to a center trunk basically. There should be a PVC cap just behind your house (maybe 2-3 feet from the house). This cap should be screwed on (threaded - not glued) This is there to remove for cleaning the line out going either way. (toward the center trunk or under the house and into the toilet). Take that cap off and see if it's full of water/sewage. If it is, your line is either plugged up, collapsed or the main sewer is full.
Good Luck


How can I mount an 12V transformer for LED lighting inside a wall? The stairs to my basement has one light fixture at the bottom, and that casts a shadow on the rest of the stairs. I want to run a strip of LED lights up the crown molding or on top of the upstairs door to illuminate the whole area better. The plan is to aim them at the brightly painted walls for light diffusion.

I don't want the transformer to be showing though. In Massachusetts, I know low-voltage wiring is legal inside walls without a permit or inspection. And I'm confident in my abilities to run those wires safely.

My concern is piggy-backing the light fixture at the bottom of the stairs. Is it legal to strip the AC wires that go to the transformer and just wire them in with a wire nut, in parallel, to the existing wires? Or would I have to actually wire up an outlet and plug it in? Is it legal to have an in-wall outlet? Is there such a thing as in-wall rated 12V transformers?

Regarding your code question: no, you cannot hardwire the transformer.

I believe this falls under NEC 400.7:

  400.7 Uses Permitted.

  (A) Uses. Flexible cords and cables shall be used only for the following:

  Pendants
  Wiring of luminaires
  Connection of portable luminaires, portable and mobile signs, or appliances
  Elevator cables
  Wiring of cranes and hoists
  Connection of utilization equipment to facilitate frequent interchange
  Prevention of the transmission of noise or vibration
  Appliances where the fastening means and mechanical connections are speciﬁcally designed to permit ready removal for maintenance and repair, and the appliance is intended or identiﬁed for ﬂexible cord connection
  Connection of moving parts
  Where speciﬁcally permitted elsewhere in this Code

At a stretch, if you could permanently attach the transformer, you could maybe consider this to be under 400.7(A)(8), but then you're still required to have a removable plug:

  (B) Attachment Plugs. Where used as permitted in
  400.7(A)(3), (A)(6), and (A)(8), each ﬂexible cord shall
  be equipped with an attachment plug and shall be energized from a receptacle outlet or cord connector body.

Additionally, I think this could be interpreted as violating 400.8:

  400.8 Uses Not Permitted. Unless speciﬁcally permitted in 400.7, ﬂexible cords and cables shall not be used for the following:

  As a substitute for the ﬁxed wiring of a structure
  Where run through holes in walls, structural ceilings,
  suspended ceilings, dropped ceilings, or ﬂoors
  Where run through doorways, windows, or similar
  openings
  Where attached to building surfaces Exception to (4): Flexible cord and cable shall be permitted to be attached to building surfaces in accordance with the provisions of 368.56(B)
  Where concealed by walls, ﬂoors, or ceilings or located above suspended or dropped ceilings
  Where installed in raceways, except as otherwise permitted in this Code
  Where subject to physical damage

So I'd say, no, you cannot just hardwire the transformer in any way.

Additionally, you need to ensure the transformer (and all connections) are accessible for servicing. Transformers also get hot and need cooling - failure to have adequate cooling could cause the transformer to prematurely malfunction and/or lead to all the other problems of hot things in contact with flammable materials like your walls.

I'd find some area (such as under the stairs) that is accessible and unfinished, and run a new receptacle there. Then you can plug in the transformer, run the low voltage wires back to the LED strips, and you're good to go.

It's quite common to remotely mount transformers -- eg, it's very common for low-voltage under-cabinet lighting in kitchens that the transformer is located in the basement near the electrical panel or other unfinished (serviceable) area.


Is there any way to predict foundation problems? I'm considering buying a historic home >100 years old on the Chicago north shore and am trying to quantify/budget for the most expensive risks.  I assume the foundation is one of the most expensive potential problems.

I'm wondering about when foundation problems tend to occur.  Do they correlate strongly to the age of the home?  Is there a certain age at which foundation problems become more likely?

If the foundation has repaired, does that mean that problems are more (or less) likely to return for a long time?

Outside of naturally occurring activities like earth quakes, sink holes, etc., I'd say the current condition relative to the age is a good indication of what's to come.

There's no real answer to this without inspecting the foundation.

An old, well built foundation that has never had problems and shows little sign of damage (cracks, crumbling, staining, holes, etc.) might last 100 years longer if maintained.  A 5 year old foundation that was poured sloppy and has had water seeping in since day one is more of a risk.

A home inspector would be able to give you a good opinion as to the quality and current state of the foundation.

You could also ask some neighbours with similarly aged homes what their experience has been.

Beware of something that looks too good for its age. It's unlikely something 100 years old wouldn't have cracks or some water staining.  If it's been repaired, the quality of the repair needs to be looked at to ensure it's not just a façade someone put up to sell the house.  A good quality repair on an otherwise intact foundation wouldn't be a huge risk in my opinion.


What is this water cap/valve for? We are considering replacing the water main/gooseneck that supplies our 1920 Washington Dc duplex home. We think it is probably original galvanized pipe. While it is not leaking and we have reasonable water pressure we are going to be tearing up our yard and the laying a rat slab under our porch where we assume the water main runs, so now would be the best time to do it.

right over our property line between the sidewalk and street (about 40 feet from our house) is what I believe is the access point to our water meter and shutoff.

About 30 feet from there and 10 feet from our house is this cap/valve. What is it for?

I'm not sure what the first one is, but you're probably right about it being a meter. Around there they're all inside.

The second one is the city's shutoff for the branch to your home. You can see that it has a pentagonal nut, similar to what's on a fire hydrant. If you move out or quit paying your bill they use that to discontinue service. They're usually near the property line, though, so it's odd that yours is so close to the building.


Do you have to pull up vinyl flooring before tiling bathroom floor? Do you have to remove old single layer of vinyl flooring before tiling?  What is best to use for under lay would it be backer board over vinyl?

There's usually some type of underlayment beneath the vinyl.  When I did my kitchen floor, it had luan board.  I would remove the vinyl.  You really just need to remove the luan board and the vinyl comes for the ride.  Then you can put down cement backerboard or even the rubber membrane.

Unfortunately/fortunately, the luan board is stapled down, which is easier than if it was glued down, but there's a lot of staples.


Basement Bathroom Drywall Behind Toilet I'm about to start finishing a basement half bathroom. I have a toilet that sits on an unfinished exterior wall. Should I have the wall drylocked, studs placed, board stock insulation installed, and green drywall put up in order to finish that wall? The toilet's water line causes me some concern about potential condensation that could form within the finished wall. Thanks, any input is much welcomed!

You can slow down condensation on cold water pipes by insulating them.

What?  Insulate cold pipes???

Sure, why not.  The insulation doesn't care. The insulation will act as a vapor barrier to keep humid air away from the pipe, and will greatly slow the warm-up of the pipe.   Remember, in condensing conditions, what is warming the pipe is the enthalpy of vaporization as water vapor condenses.  The water vapor gives up 2257 joules/gram or 970 BTU/lb. when it transitions from vapor to liquid, and this is what warms the pipe until it equalizes to ambient.  The insulation greatly slows this process, reducing condensation greatly.


How can I prevent a shower curtain from drifting into the shower's occupant? The problem to be resolved

When taking a shower, the curtain sneaks closer and closer to my body and finally, it bites my butt, which is immensely unpleasant. One person in the household lacks balance due to medical issues and can fall to the floor on occasion.

Special restriction

Due to medical considerations, it's not possible to mount a rail on the floor. Whatever solution there is, it has to be above-floor concept. If absolutely nothing else works, it might be something that doesn't create a threshold or significant elevation.

Solutions that won't work

Installing a rail on the floor will stop someone in the household from accessing the shower. Fixed wall over a part of the access way and/or partial rail will create a too narrow access path heavily impacting on the ease of use.

Schematics of the facility

The bathroom has the shower part by the far-end wall, across the whole wall, not in the corner. The person stands/sits with the back to the wall opposite to the wall with the faucet. On the right side, there's a wall with a window then. On the left, open space with toilet and sink.

Ideas for solution

I was thinking about a much heavier curtain but I fear that it will still sneak up my donkey. Another idea would be a magnet in the wall that the curtain connects to. I suspect that the middle part would still "baloon inwards".

The request/question

What would be a nifty way to approach this matter? Can any of my ideas be set up in a functioning way? Anything else that I should consider? I'm trusting that there's a nice way to resolve it because people generally have butts and most of them shower.

This is at least easy to try:  Go to a place that makes vertical blinds.  Buy a handful of the steel plates they use to keep them hanging straight.  Pick up some 3/4" diameter disk magnets.  Put plate on one side of curtain, and a magnet on the other.

If this works, then buy a can of that vinyl goop that you dip tool handles in.  Dip the plates into the goup.  This will keep them from rusting, and if they swing against the wall tile they won't leave a mark.

The weights are easily transferred when you install a new curtain.

If you have a delicate finish on your tub, you may want to change the style of your weights to reduce the chance of scratching:

Weights have beads of silicon seal on them.  Or use rubber drawer bumpers (See Lee Valley Tools)


Efficient whole house heating on a budget. Electric baseboard? Here's the question, read below for the back story and details.

1100SF row home shell.  LNG and 200A Electric service but at the moment leaning towards all electric. Considering upfront capital, long term efficiency and long term maintenance, I'm looking for the best heating solution and could use some insight.

A little back story here.  I'm flipping a row home which will be primarily for student housing.  While this is not my first flip.  It is my first flip for student housing and also, my first flip where I am hiring a contractor.  The goal here is a cost-effective flip given the intended tenants,  not cheap. My budget is 80K for a 1100SF home.

Also, this home is in an old area of the city where natural gas headers are at best an unknown variable but in some cases filled with sediment and sometimes collapsed.  The contractor proposed going all electric since we are redoing the electric anyway. I'm not married to this idea, but not opposed to it if it is necessary, or I can get incentives from the electrical company.

I'm concerned about heating. The home appears to have had forced air in some of the home at some point.  However, it doesn't appear to be balanced and is in really bad shape. This is a clean slate, even some of the sub-floors are being replaced.  The contractor seems to think that each students room should have its own heating control, and suggests electric baseboard heating.  I do like the fact that there would be less maintenance involved but the independent controls seem a little superfluous, and I was under the impression that electric baseboard heat is horribly inefficient.  Since there is not a fluid medium with any heat capacity to speak of, if it is not running, it is not heating.  I'll be putting in new R13 and brand new windows which will help, but I'm still not sure. I'd like to know what my other options are.  Most homes I've worked in had an existing Hydoionic system to work off of.  So the decision of what type of heating to use for both long term efficiency and reasonable (not minimal) upfront capital expenses somewhat eludes me.

Electric baseboard is "100% efficient" - all the heat gets used in the house. It's also horribly expensive to operate, and not remotely the most efficient "all-electric" heat, which is a cold-climate heat pump(CCHP) that can be 250-300% efficient. Also known as mini-splits.

The only "advantage" electric baseboard has is that it's cheap to install. It can also cause fires if furniture or drapes are pushed too close to it.

Many utilities have rebate programs for installing a CCHP. Some states do as well.

Depending on utility rates, natural gas or CCHP are the most cost effective form of heat to operate in most places that have natural gas available. As far as I can discern from your question the area of concern for that would appear to be the domain of the gas utility, so perhaps they would be willing to investigate if you are considering connecting to their service.


How can I stop this downspout leak? The image is outside of my house where the down drain leads away from the house. The water flows in the direction of the arrows, and leak occurs where the "T" connector connects to the outlet. I tried pushing the T-connector into the outlet more, but it didn't help.

This type of pipe and fitting is meant for burial and is not made to seal. The pop-together fittings just ensure the pipe stays together, not leak free.

If you want water tight sealing on the joints, you need to use PVC thinwall sewer/gutter drain pipe. It will have the same adapters so you can get a proper water-tight seal for the sump pump drain, a nice rectangular adapter for the downspout and glue-together slip fittings that can be cement welded for permanent leak-free operation.

Barring that, you could try popping the connection back apart, get some poly-foam backer rod, tack it into the corrugation that will be inside the connector with some silicone and see if you can make a water seal with that. It will only have to cover 2/3 of the circumference on the bottom side of the joint.


What can be used to prevent my windows from sliding down? I have wooden windows in my home, they came with a pulley mechanism to hold them up once they are opened. However, some of the pulley's cord popped, so now when I lift the lower window open and let go it falls back shut.

Are there any thing I can buy to keep the windows open without me having to wedge them ? I was thinking maybe they sell the Pulleys independently ?

Thanks in advance.

Picture of window style:

This might go against your "wedge them" restriction, but I saw these when searching for something in the past...

The are actually for sale at this site but of course they are easy enough to make.  A simple stick would also work, but that's pretty obvious and I'm sure you considered it.


transmission wire amp rating I have a cable which has 3 wires, each wire is 7 strands of SWG 22.

I need to find the transmission amp rating for this cable. How do I go about it?

Thanks

According to this table of a wire manufacturer 7
strands of 22 makes a 14 gauge wire which would carry 15 amps.

That a good estimate, but remember your wire wasn’t likely manufactured by the company who published the table.


Can I have a clothes dryer and room heater on one circuit? I currently have a 100 amp panel (square D) with no free slots. I'm looking at adding an electric heater (1000 watts, 240V) to the washroom.

I'm wondering if I can replace the 30 amp breaker for the dryer (24 amp, 3 wire + ground) with a 40 amp breaker and run wiring from the dryer receptacle to the heater. I would use 8 ga. wire for both lengths (from breaker to dryer receptacle and from dryer receptacle to heater).

Get a 120V heater

Electric heaters are cheap.  A 240V 1000W heater is worth about $40.   You could easily spend more than that on exotic breakers and hookups.  Sell it on Craigslist and get a 120V 1000W heater.

If you hardwire it, either put it on a dedicated 15A circuit, or a shared 20A circuit. A hardwired load which shares a circuit with receptacles must be less than 50% of the circuit's capacity (2400W, which is why you can't do it on a 15A 1800W circuit unless you downsize the heater.)

Share a 40A breaker

No.  You are not allowed to put more than one receptacle on a branch circuit.  NEC 210.23.

To be more precise, 210.23 calls out the exceptions where you are allowed to have multiple receptacles on a circuit, and it lists them by ampere rating. For residential, only cooking appliances for a 40-50A circuit.

Each receptacle must have the same rating as the circuit, i.e. you can't put a 30A receptacle on a 40A circuit.  (NEC 210.21).  The exceptions are 15A receptacles are allowed on 20A circuits... and 50A receptacles on 40A circuits (because no 40A receptacle standard exists).

Duplex breakers

The usual way to solve a "box cram" problem is a quadriplex breaker that puts two 240V 2-pole breakers in two spaces.  Quadriplex may not be available in 3/4" wide breakers.  But you don‘t need them to be.   You can get two plain 120V duplex breakers and use them for four of your 120V circuits.  That will free up two spaces for your 2-pole breaker.

Sub-panel

Given the criterion of using the on-hand parts (240V/40A breaker and heater), sub-panel is the way to go. Put in a 240V 40A sub-panel and put in any circuits you please, does not necessarily have to include the dryer. In fact I wouldn't put the dryer in there. I'd move over as many 15-20A 120V circuits as I possibly could, to free up spaces in your main panel. You could certainly put at least six 15A circuits - I'm not familiar with the rules on panel fill. You could even put this sub-panel right next to your main panel to make it easier to move circuits.

Do not be bashful about buying a large sub-panel.  Cheaping out and getting a panel with too few spaces is how you got in this pickle in the first place.  You might even think about planning the sub-panel so it could become your future main panel.

It is totally OK to buy a sub-panel which is rated at a larger amperage than you are using.    It is also OK if your sub-panel has a "main" breaker larger than your 40A  breaker.  That main breaker will simply be redundant.


Clarification on NEC requirements for Fixtures ( Danger ) I've recently had a problem with 2 of my ceiling mount light fixtures in the kitchen that were both on dimmer switches ( 2 different models of switches ) I had to replace 3 lights ( incandescent ) in 3 months which I found odd, So i removed the first fixture and found that the white wire was black and crunchy, So i checked the fixture across from it on a separate Dimmer switch and also a separate 15A circuit with 14/2 wire and it was also black.

Most people would jump to saying It's the resistance of the wire that's causing the high heat or you have a hairline short. All the connections were very secure, and the socket was still in new condition and had tight connections on the pop rivets and in the corn ties ( socket was rated up to 660 Watts 250 Volts with 18 Gauge wire rated for 60 C Minimum )

So then i checked the power coming in at the fixture and from Ground to Common I got 120 Volts and from Neutral to Common i got 120 Volts So i thought could it be the dimmer switch, What are the chances of 2 different dimmer switches on 2 different circuits heating up the fixtures just in the kitchen, Because i removed all of the other fixtures around the house that are the exact same and there's no heat issue with them, They're also on normal switches

So it had to be the switch, right !

I replaced both switches with normal on/off 14 A simple switches and both fixtures for safety and i took apart the switch itself to look for any arching, On one of the dimmer switches what looked like an orange capacitor was burnt and arching, but the 2nd switch on the 2nd circuit was fine, So really I'm lost at this point and sort of worried about a fire even though i changed the parts

I think It's probably best to change the white wire that has turned brown also  for safety but i came across some forums that say "NEC" Doesn't allow "NM Romex wire" So what sort of 14/2 wire is used and allowed for light fixtures, Also any insight on why a wire would heat up like this even though i was getting 120V and had tight connections with newer sockets would be much appreciated, as a final note: I though maybe because it was a dome light fixture with 2 lights in each fixture, and the fact that we kept it on all night that, that would heat up the wire, But i tried a 9 Watt Dimmable led light and it got hot pretty quick, These are the type of lights that are suppose to stay cool if I'm not mistaken, Our house was built in 1982

https://www.fs.fed.us/database/acad/elec/greenbook/3_basicdesigns.pdf

Similar light fixture to ours

https://www.homedepot.com/p/Commercial-Electric-13-in-2-Light-Brushed-Nickel-Flushmount-with-Frosted-Glass-Shade-2-Pack-EFG8012A-BN/202064742

I have found even fixture wire in fixtures damaged when larger than specified wattage lamps were used in the past, in several cases the damage may have been a decade old but after several lamp changes the wiring failed. A dimmer can not cause this problem and will reduce the heat generated because the waveform going to the lamp is reduced thus less power less heat. The type of wire needed is fixture wire it is high tempature wire designed to handle the heat but even it can become damaged if a larger wattage lamp is installed than the fixture rating. The next question folks ask is how could 18 gauge wire be legal? It is based on the load of the lamp 60w /120v = .5 amps code allows 18 gauge in signal circuits to be 7 amps. So the wire is large enough but a larger lamp may have cooked the wiring in the past.


How to check which wire is switched live? I just replaced an existing dimmer switch (with two dimmers). I noticed that the previous wiring used what I understood to be the wrong colour codes.

One dimmer had blue => C and brown => L1.
The other had black => C and red => L1.

The blue and black wires are not banded or otherwise marked.

My understanding was that brown (and previously red) were permanent live and should go into C, so for my new dimmer I swapped them around and the lights work the same.

I know that doesn't mean they're safe, so should I keep the original wiring or use the new one based on colour? Is there any way to know for sure which is the switched live?

You figure out the live by using a voltmeter or voltage detector.  If a voltmeter you compare it to neutral (or earth will suffice for testing, if present.)

You figure out the switched-live by noting which of the  live wires is off with the switch off and dead with the switch missing.

Generally you are stuck with the colors that twin-and-earth come in: blue and brown (or black and red, I assume you're going back to those colors after Brexit completes?)   So using a different color wire is not a luxury you have.  Thqt's why I own 10 colors of tape, but many installers do not bother especially if the usage is obvious.

If power (always-live and neutral) are coming through the switch, the wire past the switch to the light will need neutral, so its usual neutral wire color must be used; the live color gets used for switched-live.  i.e. You will see two blues spliced together in the back of the box and two browns on the switch.

If it is what we Yanks call a "switch loop", power comes to the light and only a single twin-and-earth goes to the switch. Neutral is not in the cable even though a neutral-colored wire is present.   One is always-live and one is switched-live, anyone's guess which.  The switch either connects them to each other, or does not.  Dimmers might care which is the always-live, but if it's wrong, they just wouldn't work.


I want a cheap solution for water heating, maybe even something I can build myself, please give me some ideas I have a little problem, over summer we choose to run a wetback for our hot water, on some days over summer this is unbearable, please provide some helpful suggestions, things like solar ovens, solar heating etc.

Unfortunately nothing in life is incredibly easy, and solar is no different.  I would NOT suggest attempting to install it by yourself or even with the help of some untrained friends.  Most average people wouldn't attempt to install their own electrical, or even their own water heater, but for whatever reason, some people believe that solar is easy.  It's not.  If you can't install your own water heater, you shouldn't even think about installing solar yourself.

What you can do, however, is analyze whether or not you are a good candidate for solar in the first place.  You might find that you are a great candidate for solar, or you might be able to mark it off the list, narrowing down your options, making your decision eaier.

Question #1:  Since you are in the Southern hemisphere, you want it on the North side of your roof.  How much available roof space do you have on the North side?  Solar hot water panels, for typical homes, will require an area between 9'x9' and 18'x9' in size (horizontal x vertical.)  (Note: If there is no room on the Northern roof, but you can install them on the ground near your house, then that is also acceptable.)

Question #2:  Are there any trees or other objects that will shade the Northern side of your roof (or the ground location)?  If so, would it be reasonable to remove the objects causing the shade?  Shade between 9:00 to 3:30 should be avoided, and shade between 10:00 and 2:30 is unacceptable.

Question #3: Is your storage acceptable for solar?  You should have roughly 10 gal + 20 gal/person in storage.  You should have an electric/gas heating element within the last 40 gallons of the hot water outlet... and plenty of storage near the cold inlet that is heated exclusively by solar.  The element near the hot out is there to heat the water in case there is no solar input, and the storage space heated exclusively by solar is required so that the solar can have a chance to heat the water without having to compete with the electrical/gas element.  For this reason, a two-tank setup is ideal.  In the diagram below, the cold water enters the tank on the left, which should not be plugged in or connected to gas, instead being heated exclusively by solar, which feeds the tank on the right, which should be heated by gas/electric.  With this setup, solar should be able to provide ~85% of your hot water.

Question #4: How many "sun-hours" do you receive in your location?  (This is not equal to simply how many hours of the day that the Sun is out, but is a measure of how many watts per square meter fall at your location.  It is a product of intensity/angle, duration, and cloud cover.  Any measurement that you might find from a location within 100-150 km is sufficiently close.)  Low exposure to the Sun can be compensated for by installing an additional panel, but if your area gets under 2.8 sunhours/day, I don't know that I'd recommend solar.

If any of the above concerns are applicable and not rectifiable, then you can cross solar hot water off the list.  Unfortunately, not everyone is a good candidate for solar, and solar HW systems that are designed poorly are a waste of money, but well-designed systems installed on homes that meet these minimum requirements work exceptionally well and will produce hot water at a fraction of 15 cents/KWh electric.. or even natural gas.  Though certain components will need replacing, sturdy flat-plate collectors should last 50-150 years (in a drainback system) and withstand up to baseball-sized hail.

Though I cannot install it for you, very detailed information is available on my web site's page on how solar hot water works.


Is it possible that I could have a 240V circuit with no circuit breaker? Is it possible to put in an electrical circuit without any way to interrupt the circuit?

I tried to work on a 240V outlet, and it wasn't marked in the breaker box. I threw every breaker, and that outlet remained hot.  For that matter, there's not a master breaker, either.

If there's no main breaker, then there is probably another breaker box somewhere, possibly in the same enclosure as the meter.

Also, it's possible that the panel you are looking at does not have a main breaker at the top; it could be one of the breakers mixed in with the branch circuit breakers. If you can, post a picture of your breaker panel with the cover removed so we can see the wiring inside.


Represurise Vaillant Turbomax gas boiler - turning filling screws, but won't fill I have a Vaillant Turbomax boiler (unsure of exact version as I don't have the manual).
The pressure is a little low so I'd like to refill. I've followed these instructions:
http://www.vaillantservice.co.uk/Vaillant_Boiler_Self_Help.html
("Turbomax Filling Loop Mechanism" section)
But nothing seems to happen when I turn both screws 90 deg. I can't hear any water flowing and the pressure isn't changing. Any thoughts? I'm currently on about 0.5 bar. Many thanks

For anyone who experiences the same: It turned out to be a blocked filling loop. We removed the filling loop (flexible silver pipe) and pocked a thin wire through it until the blockage was dislodged. Reattached and all now works fine.


Importance of plaster repair skills/experience I have an old 1920's house in the Chicago area with many lath-and-plaster walls and ceilings.  We are going to be removing a whole-house fan, which will leave a 3' square opening that will need to be patched.  There are also a few other spots, such as the area around the thermostat and some electrical boxes that need to be filled.

How important is it that I find someone who is skilled at plaster repair?  Is it something a typical handyman or painter can handle, or do I need to find a specialist?

Also, I've seen several contractors who specialize in plaster and stucco; are they similar skill sets?  Should I assume that someone skilled at stucco work is also skilled at plaster work?

Should I assume that someone skilled at stucco work is also skilled at
  plaster work?

No you should not!


What type of plastic water supply pipe do I have in my crawlspace? The hot water line under my crawl space cracked so I am trying to replace myself. The existing pipe is grey,  has CTS 3/4" 7/8 O.D. print and connected with brass ring clamps and fittings.  So I bought sharkbite pex pipe 3/4" from Lowe's and after removing the existing pipe I found out the new one is thicker and can't slide onto the existing fittings.  The Lowe's one has a thickness of around 3.5/32 in and the existing one is around 2.5/32" (0.078).where can I buy the same thickness of the existing one or if there something I can do,  Please help.  Need to DIY to save money.

I think that is actually CTS (copper tube size) CPVC. It is smaller and thinner than the normal sized PVC. If it has cracked here it will likely crack else where so If you can get to it, I would recommend replacing the entire run with one piece of PEX. And making the end connections in an accessible space.


How do I divert rain water that collects between two shed structures? I have a pvc hoop shed that sits against the rear of my main resin storage shed. The rainwater flows down the taut tarp of the hoop shed & gets into the main shed floor. What's the best method to divert the water away?

Resin storage shed

Hoop Shed: (older pic that still shows how hoop shed is flush to resin shed on one side and deer fencing on the other)

i would wedge a length of plastic gutter on a slight slope between the 2 sheds , making a small gap and encouraging the water to run into the gutter and into a down pipe directing it away from both sheds. You may have to experiment a little for the height of this


Wiring E27 lamp holder with switch how do I wire this lamp holder? http://www.creative-cables.co.uk/33985-big_default/e27-lamp-holder-with-switch-black-bakelite.jpg I am confused by the switch.

I live in Sweden if that matters. I have a regular cable without earth.

Thanks!

Hej!

Jag har sökt samma svar i ett par veckor och blev glad att se bilden du länkat till. Plötsligt slog det mig att ena ledaren kan först fästas på brytarens nedre fäste och den andra på "plattans" fäste som inte "spiken" kommer upp till. "Spiken" kan skruvas fast sist på rätt höjd eftersom det finns en öppning kvar vid det skruvfästet tills man sist skruvar ned själva lamphållarens "rör". Ja du hör ju att det inte är en elektriker som talar, men det blir faktiskt en krets med vippbrytaren som öppnar/sluter som den ska. Jag skruvade ihop den på några minuter. Ska våga prova den och återkommer!

Hälsar Ulf

Yepp, det funkade!

Ulf

In English:
One leader attached to the bottom of the switch part and the other leader attached to the part connecting to the lightbulb. The bent "nail" fixated finally to the right hight in the last hole and it can be twisted together. This makes an electric circuit, but I am NOT an electrician by far and will welcome any confirmation that this is the right and secure way to assamble this. I will check with my electric store and return shortly.

Regards Ulf

Yepp, worked like a charm!

Sorry about the Swedish and my poor explanation (in both languages). Stupid as I am I did not think of taking a photo of my first attempt of wiring and since it did turn out to work I am not dismanteling a fully operational light. However I have marked on the photograph provided by the questionaire how it's done.


RPC trips separate GFCI circuits on start up. Why? I have four 20A GFCI breakers each handling a string of outlets on each wall in my garage shop.  I also have an 100A circuit for a 20HP RPC (Rotary Phase Converter).  When I start the RPC it trips two and sometimes three of the GFCI circuit breakers. I can reset them and they are fine after that.  What's going on?

George that is a soft start. This is a way to reduce the current on start up the common way is twin SCR’s that are pulsed on until the motor is at speed. This creates a large amount of harmonics that end up on the neutral and even the ground circuits. If you look at my original comment I thought that might be the case. Line reactors on the incoming line may be the best in this case, however RFI filters on the line side may also work but a good ground reference is needed for RFI filters , I have seen harmonics cause 20+ volts on the neutral and 13+ volts on grounds and this affects other circuits like you are experiencing. One way to see if this is the problem is to monitor the neutral to ground voltage when you start the system.  More than 2.5 volts in my experience not only causes GFCI problems but can cause switching power supplies like in computers and many lighting circuits to malfunction because the reference voltage is shifted. We see this in industrial facilities quite often and use line reactors mostly. 20 hp in a home based system is more than 2x anything I have ever seen and 4x normal homes in my experience.
Edit : whoops I thought it was 20 Hp not 20 amps. Still similar issues but a 1-2 hp motor may be able to be soft started without a line reactor but RFI filters may be the best option. I would suggest checking your homes grounding electrode system. Not that many years back a single water pipe feeding the home was totally code legal but with updates to plastic pipe some of these homes end up with insufficient grounds and the reason multiple grounding electrodes required today or supplemental ones.


Outdoor party lights keep burning fuses I just bought several strings of lights.  At first they were fine, but then they keep popping fuses.  The lights say they are 60 amps.  Can I replace the fuse with higher amp or what do I have to do to keep them running?

I would say it is not safe to replace the fuse with a higher amp fuse. If the fuse is 15 amps, that means the wiring can handle 15 amps. If you allow too much current over too little wire, things get hot, fast. You definitely don't want an electrical fire. So let's troubleshoot the problem instead...

If you're running a lot of those strings and there's other stuff on the circuit (e.g. a fridge or air conditioner) you might be overdrawing and tripping the fuse.

What else goes out when the lights go out?
How many strings of lights are you linking?
How many amps is the fuse that keeps blowing?


Joining two different tile We recently had wood-look tiles placed in our living room.  There were already some retro-looking tile in front of the fireplace that we liked and complimented the wood-look tile that was going in.  Is there something that can be placed to join the two different tiles, kind of like a bullnose, but needs to be narrow and has a finished edge?  There is a slight height difference between the 2 tiles (<1/4").

Extruded tile edging is typically installed underneath the tile before it's laid. If your existing tile is at a higher level, this probably won't work as you'll want the outer face of the edging oriented toward the lower tile. It is possible that the hem on the inner face will be tall enough to do the job, however.

Another option would be a beveled marble transition strip (threshold). By placing the bevel toward the lower tile, you'd have a nice finished elevation change.


Drilling holes in concrete I'm not what you'd call a handy guy, and now wife wants me to put up curtains. This task is reduced primarily to getting a bit of metal stuck to the ceiling.

I bought screws and anchors. The anchors are a bit shorter than the screws. The clerk in the store told me that's normal. After some soul searching, I managed to drill the holes as deep as the screws. At first, I was worried that the holes were too big, since I can put the plastic anchors in with my finger.

When I try screwing in the screw, I'm physically unable to turn the screwdriver about halfway in (at this point I'm unable to yank it out of the hole either, so I'm assuming that the plastic bit expands on the inside). I don't have one of those screw-driving thingies, but I attached a screwdriver instead of the drillbit on the drill I used to make the hole, and it just "jumps out" every time I press the trigger.

I'm confused. The only possibilities that I can see are as follows:

I am not strong enough and the drill is in high gear so it can't be used this way.
Somehow I managed to mix up the anchors and the screws.

Well, here are the culprits:

Oh, don't worry about the hole in the background. That one hit something shiny, so I abandoned it. Anyway, that's about as far as I can screw it the screw without losing my cool. Oh, it's my ceiling btw.

No, this isn't normal. Your anchors don't fit to your screws. What is happening is that the tip of the screw reached the concrete, and, of course, you can't force a screw into concrete - not even with a drill or a electric screwdriver, and certainly not by hand.

This picture shows how anchor and screw should fit into the hole. The hole definitely needs to be longer than the screw. The screw should be a bit longer than the anchor, but not as long. Maybe the clerk saw that you have picked an wood screw and gave you anchors suited for the second situation. It doesn't hurt to use wood screws with anchors in a concrete wall, you'll just have the cap jutting out a bit. But the length of the screw should be only a bit longer than that of the anchor (the surplus should equal the length of the tip + the length of the attached thing), and your cap will stick out a bit if the thing you are attaching isn't soft enough for the cap to sink in.

The table shows how to determine the correct hole depth. It also tells you what diameter of anchor and drill to choose for a given screw. As for the length of the screw, it is determined by the weight it will have to carry. Vertical screws are more problematic than screws in walls, because gravity is pulling in the direction of the hole, not at 90° to it. Light curtains will be OK with your size screw, but don't put any molton on them.


Hitachi brad nailer - firing it empty against a hard surface I just bought a brand new Hitachi brad nailer, and part of the "testing process" of ensuring that it operates as normal is when you get it, make sure it fires when the nose is depressed against a surface (among a few other things).  One thing I'm not sure of is when you "test fire" this against a hard surface, whether it be wood or concrete, surely that's not good for the "hammer" in the unit, is it?

Don't dry fire brad nailers against anything you wouldn't drive a nail into. The instructions (PDF) specifically state, "against the workpiece," don't they? Use a scrap piece of wood for the initial testing. You may also want to limit dry firing to initial setup and any future troubleshooting procedures. Many newer nail guns have a dry-fire lockout that prevents the tool from firing when fasteners run out. This is partly to protect a workpiece from being marred by the hammer, and partly to extend the life of the tool.

Why would you test fire it against concrete? You bought a brad nailer, not a Ramset!


Flickering light at outlet tester Scratching my head after trying to troubleshoot some failed outdoor lights. It is a long story.
The issue was with the outdoor lights outside my garage door. There are 3 sconce lights, and one overhead light that is controlled by a motion detector. All 4 lights are controlled by a single switch. There are other lights inside the garage (including garage door opener) that shares the same circuit breaker, and they are working fine. This is a relatively new house, originally built is 1996, but significantly upgraded in 2006.
Wife complained that the overhead light always stays on (i.e. not controlled by motion detector), and the sconce lights never turned on.
I first tackled the overhead light. The motion detector was bad; so I changed the motion detector, and it started working correctly. So far so good!
Then I started checking if any power is coming to the bulb holders of the sconce lights. Verified that all 3 bulbs are good. Also put a "Lamp Holder to Outlet Adapter" in the bulb holder, checked the voltage  using a multimeter, and got ~120V between hot and neutral.
However, when I connected a LED light to that adapter, I got a very dim output. Also tested it using a "Klein Tools Digital Circuit Breaker Finder/Receptacle Outlet Tester", making sure to connect the ground wire to it as well. It showed correct wiring (2nd and 3rd yellow lights were on), but these lights were dim and flickering. I saw the same issue at all three sconce lights.
In addition, if I connect a light bulb to the bulb holder, then the outlet voltage drops down to almost zero, even though the light bulb does not turn on. If I use a CFL bulb instead of filament bulb, I see a faint flickering.
At this time, I found that the overhead light has stopped working altogether. I removed the overhead light, and saw the same issue there as sconce lights; i.e. 120v but outlet tester was showing dim/flickering lights.
To isolate any issue with the devices, I completely removed all the 4 lights, leaving only the wires coming out of the outside wall. Still seeing the same issue.
As the next common point was the switch, I removed the switch completely, and connected the black wires together. Still no change. Also, if I use the outlet tester at the switch, then the two yellow lights are bright and steady. I also checked that the neutral wire at switch box is securely attached with the other neutral wires (there is another switch in the same box).
At this point I am at a loss. I hate to think that this is a wire issue, because the wires go above the wall of the finished garage, and not easily accessible.
Is there any other experiment that I can do?
Thanks.
PS: Adding more datapoints based on the suggestions below.
Tried these experiments:
(a) Connected an Edison bulb to one of the sconces, and on 2nd scone bulb-socket, attached an extension cord to bring the point near the switch. With the light-bulb connected, the voltage between the hot and neutral of extension cord drops to 1 volt. Now, I checked the voltage between neutral of extension cord and that of the switch. It was 0 volt. Next, checked the voltage between hot line of extension cord and that of this switch. It was 120volt.
(b) With bulb removed and power turned off, I measured resistance. Between neutral of switch and extension cord, it was 0 ohm. Between hot of extension cord and that of switch, it was about 6 M-ohm. This should also ideally be close to 0, right?

Everything you have observed points at a bad connection with high resistance. When the load is small (voltmeter or neon test lamp), the measured voltage is high, and when there is a larger load, the voltage drops. LED and CFL lights may flicker because they can start with very little current and they have capacitors in their power supplies enabling momentary running on the tiny available power, but an incandescent bulb will stay dark because it never gets hot enough to be visibly lit.
You will need to find the bad junction. One way to do this is, while there is a load (the sconce lights), to put a voltmeter across two different points on the same wire (both hot or both neutral). Good wiring should see no more than a few volts, and usually much less; a bad connection will show somewhere up to the full 120 volts. If you see a large voltage, the bad junction is somewhere between those points, and you can then test further within that span, or inspect all the joints. You may need extensions for your meter's leads to be able to reach.


Are floor joists allowed by code to be notched at the ends? I'm repairing termite damaged floor joists in the crawl space a 1940s house. At the chimney, there are double 2x10 trimmers and headers as you would expect but on each side of the chimney one of the joists tieing into the headers is a 2x12. The ends are notched at the sill plates and they aren't under bearing walls. I can't find any current code requiring this and the way it's notched it may as well had been a 2x10. Is their a reason for this one joist to be a 2x12 or was this just something that's no longer required?

The stress on a joist reduces substantially near the ends. For this reason it's often the case that engineered joists have a narrower (shorter) bearing point. Take top-hang truss-joists, for example:

Image source

Another example is the typical rafter truss. Obviously those are very small at the ends.

Whether your situation meets any sort of code is somewhat irrelevant. It's a 1940s home, after all. The bigger question is whether it works, and apparently it does. The joist is larger than the others probably because it has a wider spacing due to the chimney, or because it carries some additional load.

If you're concerned about passing inspection, have a conversation with your inspector. (S)he will specify whether replacing like-with-like is adequate, or whether you'll be required to get an engineer to sign off on a modern approach.


Want to install an outdoor ceiling fan directly to exposed 2x4 on a covered porch The above picture is not my roof but nearly identical. Except my roof also has horizontal 2x4 supports. The previous owner has a shop light running horizontally screwed directly into the 2x4. I want to install a ceiling fan but am not sure how. I know I can install a box that directly mounts to the 2x4 that is fan rated but I thought the canopy of the fan would have a greater circumference than the box and there would be an exposed gap. Any suggestions? I would want a look like this

You want the main attachment for the fan box to be attached perpendicular to the floor, not horizontally into a faming member. The twist on a horizontal attachment could lead to failure. The box should be attached with sizable screws or lag bolts.

That means, you should have a framing member directly above the box, either the 2x4 you mentioned or a short added framing piece running perpendicular (vertically) to the joist.

I would build a small wooden frame around the fan box. 2x or 1x pieces should do. They are not structural but decorative and gap filling. These will give a base larger than the canopy.

I would then run a conduit to carry the cable to the fan box, making holes in the surrounding box trim.


Can't get NPT connection to not leak I am trying to connect this spigot (3/4 in. FIP Inlet):
https://www.amazon.com/gp/product/B00MA9F8RE/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
to this elbow (3/4" NPT Male):
https://www.amazon.com/gp/product/B004XUKSF0/ref=ppx_yo_dt_b_asin_title_o00_s01?ie=UTF8&psc=1
If I understand correctly, FIP and NPT are directly compatible - right?
Even with paste thread sealant (which I believe you are supposed to use for this kind of connection), and tightening it wrench tight, it still leaks. Not spraying, or even dripping, but just pooling up water enough to drip one drip ever several seconds. This seems wrong. I noticed that when I unscrew the threads, they are really clean (i.e. the paste sealant seems to have been "pushed" out entirely when I connected the two).
Am I doing something wrong here?

I put H B Smith 350, 450, and 650 screw nipple boilers together with RTV for many years as did a couple contractors I worked with. These boilers almost always had nipple thread leaks. When I or the contractors used RTV we never had a leaking nipple.
my 2 cents


How do I remove white residue on bathroom floor tiling? There is white residue on my bathroom floor tiles in areas where water regularly leaks. It looks like limescale but will not budge when I try to remove it with vinegar. How can I remove it?

That does not look like residue.
1.) if you get it wet, does it fade or change in color?
2.) if you scrape at one spot wiht your fingernail, does it come up?

Looking at the photos you've posted, I think that is both mold (in a few areas - showing that the area does indeed stay wet often as you imply), and damaged flooring.

I suspect the material of that flooring is porous and the water has actually damaged the "cheap" surface.

Also, it looks like you may have used a scrub tool on it, which has scored the surface further (the scratches and lines), and the condition will continue to get worse.

My recommendation at this point is to keep it clean and dry, solve the issue that introduces the water/dampness. you will have to replace the damaged areas to return it to like new condition.

If that is real wood, and it has a finished surface, you can probably use a buffer on it, but it does not look like real wood.


What causes the noise coming from this radiator valve? There's a hot water wall-hung radiator in my kitchen that produces a constant ticking noise when water is flowing. The noise is coming from the valve area, removing the thermostat does not influence the noise. Pushing the little rod on the valve with the thermostat removed only makes the noise louder.

I recorded the noise, amplified it and placed it here.

Is this noise indicative of a defective valve?

That's an odd noise, it sounds like something's loose inside the pipe and rattling around. Might be a piece of rust or gunk. If you remove the thermostat head and press the rod down completely, the rattling should cease because the valve is closed and there's no water flow. If the noise continues, that indicates the valve isn't closing properly.


Why I am having eye irritation problem with oil radiator in my home (in India/Asia) when I never had such problem in Europe I used to live in Europe, and I loved electronic oil radiators as well as central heating.
This year, I decided to buy an electronic oil radiator for my home in Delhi, India. But whenever I use it, my eyes feels very dry and irritated after 10 minutes.
What is the problem?

Probably paint on the outside of it off-gassing something.
Set it outside and run it on high for a few hours, that might help burn the volatiles off.
Most are too convoluted to expect removing the paint to be practical.


Thermostatic control of an unmanaged energy source to supply hot water cylinder I have a solid wood burner that contains a heat exchanger. There is no guarantee that the combustion can be regulated. This heat exchanger feeds a loop that acts as the source heat exchanger in a hot water cylinder. The loop is pumped (pump not shown in diagram) when the furnace outlet exceeds a certain minimum temperature.

As we cannot control the combustion, it is possible that the loop and hot water cylinder would overheat. I am looking to ensure that we do not exceed a specified maximum temperature.

It is very possible that there is a component that already exists to do this, so please let me know if this is the case (the more analogue the better). In lieu of such a component, I came up with the following diagram:

When the temperature in the loop exceeds the maximum desired, the thermostatic control valve injects cold water into the loop. This creates an excess of water in the loop which will then exceed the pressure managed by the pressure relief valve, which will open and then 'drain' some of the coolant from the loop.

I would appreciate some feedback on this idea. The existing implementation (not my doing) basically has no control whatsoever, and isn't immediately replaceable.

I am totally aware that this is a waste of energy, but its just a safety control - I wouldn't expect to ever trip it.

EDIT: I can see that the more sensible option here, as hinted a few times by others, would be a thermostaticaly actuated valve to release hot water from the hot water cylinder when it exceeds a certain temp which would then handle its own "mixing". I think thats what im going to do for now. I also like the idea of a separate loop that gets activated to discharge excess heat through an alternate sink. Could be handy for keeping a hot-tub, greenhouse, etc, warm - should I ever decide to take on that task :D

Thanks for help everyone. Wish I could accept a combination of answers, as they are all great!

A woodstove would never be connected to a cylinder in such a fashion.

The only use for the thermostatic valve is to control the output of the hot water tank to the user and a common setting is 46 degrees C.

The hot out pipe of the woodstove should have the combined P&T valve fitted with an expansion pressure vessel to allow for the normal water expansion due to the rise in temperature.

The woodstove manufacturer will normally specify the minimum volume of tank to be used and, most likely, so will the local regulations - perhaps also set by the local fire department.


How do I repair aerated autoclaved concrete? I got an everlasting problem with a aerated autoclaved concrete (also known as "Gasbeton") wall: there's a crack that seems to split the upper half from the bottom half of the wall.

I tried several time to fix it, either with the proper aerated autoclaved concrete putty and with stucco but, after some days, the crack comes back again.

Any idea on how to fix it for good?

EDIT: The wall is made of AAC blocks (as bricks), I have access to both sides and is an interior wall: basically it divides one former big room in two smaller rooms (kitchen and bedroom).

Instead of trying to fix the crack, first try figuring out what is causing the crack.  You can fix a crack many times, but if you are fighting against something like water pressure (or one of the many other causes of cracks in concrete), you will never win.   Once you find what is causing the crack, then look to mitigate the problem somehow (proper drainage in the case of water buildup), and then fixing it one final time will take care of the problem.


In IKEA kitchen marketing, what does 'kvm' mean? This page advertises an IKEA demo kitchen. In the panel just below the main image, it quotes the following:

  £3,060 without appliances

  12 kvm

What does 'kvm' mean? Is this a Swedish name for a unit of measure that they didn't realise they should translate? I can't find any mention of it besides the adverts themselves, and googling a number of permutations of 'kvm ikea kitchen' doesn't yield anything that looks useful.

edit: As of July 2015; the linked page still exists, but has been updated to read 'sqm' which English-speakers would readily interpret the way it is intended - 'square metres'.

This is short for m^2 which stands for kvadratmeter. This is the total area the kitchen will cover. The two terms are user interchangeably in the Swedish language. Wikipedia article (in Swedish)


How do I wire a light with only two white wires and nothing else? I bought a light that is labeled a night light.  When I opened the box I found that it has a red and black wire that lead to some sort of electrical component which I believe is related to the remote control.  The only two wires that exit this component are white.  There were no instructions at all.  I'm assuming it goes to a ceiling box from the way the bottom of the light looks.  How would I wire this into a ceiling box? Can this be wired with a plug instead?

Strange it came with no documentation.

The backward UR is an underwriters laboratories recognized component marking. It appears to have a C before it and a US after it.
https://en.m.wikipedia.org/wiki/UL_(safety_organization)#Recognized_Component_Mark

That doesn't mean the whole assembly is UL approved but it means that part has been tested.

Either send it back and get a refund, or contact the company that sold it to you for instructions.


New Door Handle wants larger main hole than is on there already The new door handle wants a larger hole, by 1/4 inch, than is on there.  What to do?   get a different door handle hoping for the right size hole, or , a new door???

Figured it out using the Related postings prior, and removed the anti-pry plate by prying it off.  Oh, the irony.  Thx, SE et al.  Those lever type door handles are the bomb.


Cellulose ceiling tiles (asbestos?) Came across this room with broken acoustic ceiling tiles, that I have to spend time working. The tiles look kinda "modern" to contain asbestos, but then again you never know. Wondered if anyone can recognize the material(s) they're made of. Many thanks.

Do you know anything about the building you have them in?  Age of the building, dates of renovations?  If you can pinpoint that it might rule out the asbestos for you.  Asbestos building materials were made illegal in North America and if you can find someone (an older person with some years in) at that place they might be able to help give you some information.  If you haven’t been working with those tiles your exposure would be minimal, for asbestos to be dangerous it must be air born and the amount of exposure determines your health risk.  So if those tiles were broken a long time ago and you didn’t disturb them in your work your exposure would be minimal.  If you have been working with them it does increase your risk unfortunately.


What does it mean when an LED bulb starts blinking randomly? Recently I noticed that my led bulb turns on/off for a split second randomly over the past few days. Does this mean it is starting to die or could it be something wrong with the lamp?

I've unscrewed to see if anything was damaged but could not detect any damage.

LED drivers are generally switching power supplies, which apply pulses of power to keep themselves charged to the level the LED needs. One side effect of this is that if there's a trickle of power available, they will still try to charge up, turn on the LED, immediately run out of power, and repeat. It's a complicated form of a "relaxation oscillator."

If your switch has a light or remote-control circuit that is powered by allowing a trickle of current through the load, or if you have a dimmer which fades far down but isn't cutting off completely, you'll get this effect.

For what it's worth, sample-to-sample variation means that different LED bulbs will blink at different rates for a given underpowering level. I have a 16-bulb fixture in my living room which, when faded down, does a nice imitation of christmas tree lights, "randomly" blinking in unpredictable patterns.


How long before I can move a concrete lid? I cast a concrete lid to replace the broken one on my well pit. My lid is 30"x 36", and 2-1/2" thick and reinforced with rebar. I am keeping it covered with a tarp and misting it every few hours. How long before I can safely move the lid to my well pit?

As a teenager, I had a summer job pouring concrete to cast septic tanks and their lids.  The lid of a septic tank is exactly what you're creating - we made them in circles about 5 feet across and three or four inches thick with rebar inside and three rebar hooks for lifting.

Each morning, we would use a front-end loader (tractor with a bucket on front) to pick up the lids we had cast the previous day.  These would be set aside to cure for another few days before installation.  Then, by the afternoon, we would have the forms set up for pouring again.  The concrete arrives at 1pm, we pour by 2pm, and then mist the tops to keep them from cracking until sundown (Texas heat).  Like I said above, by morning, the lids are able to be moved and we start the process all over again.   Based on this, I would say that the lid can support its own weight after 24 hours, and will fully harden over the course of a few days.

To give yourself a safety factor, double those numbers, so go with this:
Wait 2 days to move it at all, and wait 5 to 7 days before putting it into place.


What is this small hole and why is it there at the bottom of sink? I installed a new faucet and drain pipe assembly. I found that there's a small hole at the bottom of the sink (underneath). Water is coming out of it. When I pull up the stopper (so the water collects inside the sink), there's no leakage. But as soon as open the stopper or open the faucet, water is start dripping through this hole.

Anyone knows why is it here, why is it leaking, and how could I fix it? There didn't seem to have a cover or "plug" for it previously.

Thank you.

This looks like it's tied into the overflow system for the sink. Your old drain pipe might have covered it up. If the old gasket will fit on the new drain pipe you could just reuse it or get a duplicate gasket from your plumbing supply store. I would hesitate to just plug up the hole because you never know when your plug would fail and you'd have a big leak. It could also compromise your overflow protection. You could also just put the old drain pipe back on the sink if you can't get a new exact match.


Possible Electrical Short After Drywall Installation I just finished tearing my office down to the studs, insulating, and then having drywall installed. The crew did the drywall install today. I have a light switch which is a dimmer that powers 4 "cans" AKA recessed lights. After the drywall install I flipped the switch and the lights came on with a loud POP noise. I turned the switch off and then on again. This time nothing happened for about 5 seconds and then the lights came on. I turned the light off and on about 50 more times and now it always works but there's a low hum that did not exist before. I suspect an electrical short situation was created during the drywall install but I'm not much of an electrician. Where should I look for problems and how should I solve this? Will my house possibly burn down?

This sounds like a rather dangerous situation. The drywall installers no doubt did not install metal straps on the studs wherever an electrical wire crossed through the stud. Most likely a drywall screw or nail has gone into the stud and entered a wire that crossed the stud in the same place.

The fix for this may require a professional electrician unless you are pretty familiar with electrical wiring work. It will be necessary to cut the power to the circuits and open all the applicable electrical boxes and disconnect the various lights, switches and power feed wires. Then shorts checks can be made using an appropriate ohm meter for all the wires in the area between the boxes.

Once the short is located it will likely be necessary to remove the drywall in that area to replace the wire.

Do not leave this problem go. It sounds like you have a medium resistance short in some wire/stud crossing. I say medium because you did not mention that it is tripping a breaker. The resistive short can produce a lot of heat and could definitely lead to a fire in your wall or ceiling.


2 switch to one - Similar but not the same I have  outside security lights on two separate switches.  I am remodeling and have removed a door and now only want one switch to control the security lights.
When disconnecting the one switch I think I opened the circuit and now the other will not operate the light.  I am wondering if I should connect the red and Black with a wire nut and cap the other black in order to close the circuit and have the one switch work.

The black wire going into the groups of black wires with the red wire nut is your feed. The solo black and red wires were your travelers to the other switch. Connect your feed to one of the travelers. Try your other switch. If the switch position is correct, toggle up is on, toggle down is off, you're good to go, cap the unused traveler. If not, then connect the feed to the other traveler and cap the unused one.
Put a blank box cover over the box without the switch. It has to remain accessible and can't be drywalled over.


Should my carbon monoxide detector be reporting zero PPM? I've got a Carbon monoxide detector hanging in my kitchen for a few years now. Lately I've noticed it reads a PPM of 0 (zero). Is this right? Doesn't the air contains around 400 ppm?

In other words, is my detector even working? I'm getting the feeling I should throw it out.

No, 400 ppm is NOT a safe level.  Here is the US Govt. CPSC information on CO:
CPSC CO Information
To quote the relevant part:

What CO level is dangerous to my health?
The health effects of CO
depend on the CO concentration and length of exposure, as well as each
individual's health condition. CO concentration is measured in parts
per million (ppm). Most people will not experience any symptoms from
prolonged exposure to CO levels of approximately 1 to 70 ppm but some
heart patients might experience an increase in chest pain. As CO
levels increase and remain above 70 ppm, symptoms become more
noticeable and can include headache, fatigue and nausea. At sustained
CO concentrations above 150 to 200 ppm, disorientation,
unconsciousness, and death are possible.


How to attach newel post to stringer below the tread? I need to install a new newel post at the top of my stairs but there is not room on the landing for a post, it will have to mount from the tread of the top step.

My plan is to notch out the post at the bottom and sink it through the tread and bolt to the stringer below. My question is, is there a specific way to attach the post without weakening the integrity of the stringer? My main concern is how it attaches to the stringer without losing integrity.

I attached an image to show how I plan to do it.

I'd use four 5/16" x 3-1/2" lag screws through the stringer into the post, properly piloted, and construction adhesive at all contact points. Spread the screws as far as possible, staying at least 3/4" from any edges, for the best stability.

The bigger concern, though, is the attachment of the stringer to the landing. If that's not robust, your post won't be, either. If possible, add construction adhesive to that joint at all contact points, even inside and around any builder hardware (such as a hanger). Even a heavy bead wrapping the joint and tooled out slightly will add significant strength. You could also add a block to one or both sides of the stringer, against the hanging surface, and embed that in adhesive. Anything along those line will really help give you a solid post.


Electric 220 stove wiring I am replacing my electric slide in range with a stand alone model.  The original was hard wired and the new is with a cord.  There are 3 wires and a bare copper wire coming from the wall.  What should I do with the copper wire.

You will need to install a NEMA 14-50 outlet for your new stove.  Connect the black wire to L1, the red wire to L2, the white wire to N, and the copper wire to G, then plug your stove in.


Melted switch replacement Was taking a shower and smelled some melting plastic. Turns out that the switch to the heat function of my bathroom fan was the cause of the melting smell. That one switch is part of a box that has 3 other switches and that particular switch has it's own circuit due to the heater. The other 3 switches are all grounded together using one copper wire connected to each switch but the melted switch was not grounded.

Is this what caused the switch to melt?

Will a 20A switch suffice or do I need one rated higher?

The switch is a goner, so you'll have to replace it

What happened here was the initial connection at that screw terminal was made improperly (mistorqued), which caused it to overheat and progressively fail further until it started smelling...melty.  The good news is that you caught it soon enough that it didn't start anything serious (like a fire!).  The bad news is that the switch is toast and needs to be replaced with a new decorator-style double switch, preferably one rated for 20A.

When you replace it, you'll want to use a torque screwdriver that reads in inch-pounds to tighten the screws on the new switch to the specified torque (12-14 in-lbs, as per this Leviton specification, if your switch didn't come a number).  You'll also need to fit a grounding pigtail to the new switch, connecting it to the existing ground wire bundle in the box.


Installing new fixture over medicine cabinet The old light had 2 separate cables coming from wall. Each had black and white wire and ground. There was only one black wire hot out of the 4. I used that bundle to hook up fixture. Black to black, white to white. Capped the other bundle. I could turn light on and off by circuit breaker but not switch. I took black and white from second bundle added them to black and white from first bundle this just tripped breaker. Not sure what I did wrong.

As noted by commenters, you should never disconnect something without noting how it was connected in the first place. With smartphones common and handy, at least take a picture next time.

Educated guess here, but the non-hot wire was probably the switch. It's easy enough to check.

Take the wall plate off the switch and unscrew it from the box. Verify the wires are not hot. If it has a white and black connected to the switch, proceed to step 2. If you have any other colors (i.e. 2 blacks. connected STOP and get an electrician.
Assuming a white and black, turn the breaker off and connect the white wire you nutted off to your hot black wire. Now, turn the breaker on. If you have power at the switch, you have your answer. If not, STOP an consult an electrician.
Assuming Step 2 was successful, remove the nut from the black wire at your fixture and wire it to the hot side. Put everything back and you now have your switch working.


Best way to take wood glue off of tools? I try to clean my tools after working with wood glue but i always miss a spot here or there. My square is covered  with wood glue because i didn't clean it fast enough. Whats the best way to take the glue off? I don't want to damage the plastic or metal on this precise part.

Bucket of hot water and a utility knife is what I use.  Let tool sit in bucket.  Sometimes after a couple minutes you can just touch the glue and it falls apart.  If it is a strong glue it will pop off with the utility knife.

The hot water is the fastest way I know because it heats both the glue and the tool.  Heating the tool causes its molecules to contract, weakening the bond and the glue just melts most of the time.


Can I plug my E27 bulb directly into my wall socket Assuming I have an E27 lightbulb such as this:
https://web.archive.org/web/20150928143146/http://www.wartena.com/en/light-bulbs/6-philips-spaarlamp-e27-14w-65w-8710163224138.html

and I have fixed it onto a E27 mount, and perhaps wire it to a plug that looks like this:

Can I just plug it directly into a wall socket?

I'm in Malaysia and we run 240V from the wall sockets.

I don't really know how voltage comes into play here for bulbs or if a transformer is required.

Like I notice that all our other electronics have transformers. E.g. our cellphone and laptop chargers have some intermediate box that does necesary conversions.

Compact Fluorescent Lightbulbs

So long as the lightbulb is rated for 240V (and not 110V or 120V) it will work when connected as you suggest. In countries with 240V household outlets, retailers will normally supply lightbulbs rated for 240V. Check the packaging and the lightbulb itself - the voltage will be marked on them.

There is a manufacturer's datasheet for the part with EAN code 8710163224138. It says "• Voltage: 220-240 V" - so this is OK.

A home-made light fitting of this sort may not meet your local electrical safety code (i.e. law). Normally there has to be an enclosure designed for the purpose. The enclosure provides mechanical protection to the lightbulb (especially any glass parts) and provides some protection against people inadvertently touching parts that carry live current or which might do so in a fault condition.

You also need to pay attention to earthing any metal parts that are accessible.

In particular, compact-fluorescent lightbulbs of that sort are relatively delicate and, if broken, will leak mercury - which is poisonous. It is prudent to provide some protection in case the luminaire is accidentally knocked over or bumped into.

Other lightbulbs

Some lightbulbs are designed for low voltage. For example some desk-lamps use halogen bulbs that require 12V DC. These desk-lamps are supplied with a suitable transformer. These lightbulbs should never be directly connected to 240V AC.

These type of lightbulbs will never be provided in a E27 fitting. In general, you can be sure that any commercial lightbulb with an E27 fitting supplied in a well-regulated country by a reputable vendor is suitable for your local household electrical supply (e.g. 240V AC)

Other appliances

As you note, phone "chargers" and similar items contain a transformer that typically convert the household electrical supply (e.g. 240V AC) to a voltage suitable for the small appliance (e.g. 5V DC).


Fast *safe* way to add an outdoor light I want to add an outdoor light or two on an exterior wall that has no lights.

(I'm about to get a puppy and have a door out from my bedroom that has no lights. Since I live in the mountains and have seen and heard bears outside on that wall, I'd like to know for sure at 3am before going out for a puppy pee break.)

Factors:

I'd like a bright flood light (or two). Not a dim solar-powered failure.
Ideally the light would be motion-triggered in addition to some way to force it on from inside.
Some of the exterior is 8" concrete.
There is a light switch next to the door that controls an exterior light around the corner from the desired face.
There is an outdoor outlet one floor down, around the corner from the wall.
There is very little eave over the face where I want the light (maybe 1').
I need some solution (if not the final one) in place in two weeks. Hard to find an electrician in that time.

Here's a hack diagram of the situation:

I want the lighting along the exterior face on the right in the picture.
The yellow circle is the existing outdoor light.
The dotted "S" is the interior light switch controlling the deck light.
The dotted "O" is an outdoor outlet (tucked around a low concrete wall).

Is there any way I can just run an extension cord from the outlet up to...something?

Are there any LED lights that you would consider acceptably-bright for an outdoor safety flood? And solar-powered?

Can I patch into the cord from the light switch by drilling through from the exterior?

You can run the light from the switch. This is a one hour job for an electrician. It doesn't get much faster than that.


2 Layers of 5/8" Drywall in Garage Side DO I need to provide 2 layers of 5/8" type x gyp board on garage side?
Plan checker is telling me I need to specify 2 layers.

Garages are to be separated from single family residences by 1/2” gypsum board on garage side ONLY, provided the garage does not open into a sleeping room. (See 2017 edition ICC Table R302.6.)

Also the door between the garage and house shall be a solid wood door a minimum of 1 3/8” thick and is not permitted into a sleeping room. (See ICC R302.5.1.1.)

However, town houses require 2 hour separation, which requires 2 layers.


How do I remove 4 pieces of tile in my shower? I am replacing my old 3 piece grohe faucets with a one-piece shower faucet.  I need to remove 4 tiles, which will be replaced when the new faucet is installed.

How can I remove the 4 tiles without damaging the tiles I want to keep? I don't want to buy a specialty saw for just a one-time job.

Thank you!

You first cut the grout line surrounding the 4 tiles.  The cheapest tool for that task is a $10 grout saw like this https://www.lowes.com/pd/Marshalltown-2-in-Steel-Blade-Red-Plastic-Grout-Saw/1000204021.  You can remove easily 5 ft of grout line in 30 minutes with this tool and elbow grease.

Then use a drill make holes in your tiles.  Use a hammer and gently tap on the tiles.  Finally, cleanup the thinset left behind.


What is the easiest solution to add receptacle along an unfinished, exterior, insulated, basement wall? I need to add a pair of receptacles along an unfinished, insulated, exterior basement wall. I want the easiest method possible. I have no plans to finish the basement. I need each receptacle to be on its own circuit breaker.
I do not want to remove the vapor barrier/insulation and drill through all the 1.5X2.5" studs. The floor joists run perpendicular to the wall.
Does this require the wire be run by conduit along the top of wall and then down studs to a box attached to face of stud ?
Or is there another way that would meet code ?

I think the easiest solution is to cut the vapor barrier in the section(s) the outlets will be located in. Cut along the studs. The install outlets/wiring between stud/insulation. Then, simply cut a new vapor barrier section, tape to seal. You don't need to take the entire vapor barrier down (unless you don't trust the tape seal--which if true, I also  presume you'd want to replace the entire vapor barrier?)

You may not plan to finish the basement, but the next owner may. Having receptacles flush with the studs will make it easy--if/when that time ever comes.


Identify a pipe coming out of the basement floor, as well as a hole in the floor? I want to build a bathroom in the basement with a 36”x36” shower.
I am trying to figure out if this pipe is the vent from the main drain.

I am trying to figure out if this pipe is the vent from the main
drain.

It is a vent, it is coming off of the top of a sanitary tee so it is a vent for a fixture (Bathroom sink) that would be attached to the SanTee.
The pipe coming form the bottom of the SanTee is the drain for a fixture  that would be attached to it.
The hole in the floor should be the required space for a drain/trap for a shower/tub. Presumably since the sink plumbing and a  toilet flange was roughed in there would be a capped off drain pipe under the dirt.


Blower motor runs won't shut off no heat My furnace is set at 72, my house is 64. I have no heat, and when I turn the thermostat off, it continually runs.
When I'm running the air conditioner, it blows heat.
What is a possible cause?

One or more limits are open.  You'll have to determine which one is open, figure out why it's open, and then fix whatever's causing it to be open.

If you look at the control board in the furnace/air handler, you may see a blinking light (or two). Count the number of blinks in the pattern, and compare it to the manufacturer's documentation. This will often point you in the direction of the problem.

If there are no diagnostic lights, then you'll have to check each limit until you locate the open one. If you don't have the tools or knowledge to work on HVAC equipment, it may be time to contact a local HVAC company.


Is it safe/compliant for one circuit to supply grounded wall outlets in both a kitchen and a living room? On one side of my wall (in kitchen, not the refrigerator or stove plug) is a three prong grounded outlet. Would it work without overloading a circuit to put a new outlet on the other side of the wall (the living room)? Any special precautions I should take? The house is small and short on plugs, so I could use a few more. Is this OK or not OK?

National Electrical Code says no.

National Electrical Code 2008
ARTICLE 210 Branch Circuits
210.52 Dwelling Unit Receptacle Outlets.
(B) Small Appliances.
(1) Receptacle Outlets Served. In the kitchen, pantry, breakfast room, dining room, or similar area of a dwelling unit, the two or more 20-ampere small-appliance branch circuits required by 210.11(C)(1) shall serve all wall and floor receptacle outlets covered by 210.52(A), all countertop outlets covered by 210.52(C), and receptacle outlets for refrigeration equipment.
(2) No Other Outlets. The two or more small-appliance branch circuits specified in 210.52(B)(1) shall have no other outlets.
(3) Kitchen Receptacle Requirements. Receptacles installed in a kitchen to serve countertop surfaces shall be supplied by not fewer than two small-appliance branch circuits, either or both of which shall also be permitted to supply receptacle outlets in the same kitchen and in other rooms specified in 210.52(B)(1). Additional small-appliance branch circuits shall be permitted to supply receptacle outlets in the kitchen and other rooms specified in 210.52(B)(1). No small-appliance branch circuit shall serve more than one kitchen.

210.52(B)(1) basically says, that all the receptacles in the kitchen should be supplied by 2 or more 20A circuits. 210.52(B)(2) says that there should be no other outlets on these 2 or more circuits, which means no lighting outlets and no outlets outside of the kitchen.  210.52(B)(3) says that the 2 or more circuits, can be used to supply receptacles in other 'related' rooms (pantry, breakfast room, dining room, or similar area).
Even though the kitchen and living room may share a wall; according to NEC 2008, they cannot share an electrical circuit.


Adding a second hatch to the attic I have the following problem: my attic is mostly a crawlspace for the air-conditioning unit. And that crawlspace is full of obstacles, which makes my filter very hard to reach.
My solution is to make a second push-up hatch (or ladder hatch) that is right next to the filter, as opposed to the other side of the attic.
It would go here (view from crawl-space, looking down onto ceiling of top floor.)

Some googling makes me believe that I need to place a box, with Styrofoam lid in my ceiling.
Also, that is what resembles my existing hatch, at the other side of the attic.
I've measured the beams (joists?) to be close together, with only a 39cm gap between them.
I guess enough for a small hatch, of custom size?

Would I place my custom box on top of the timbers, or between the timbers? It looks like I need to re-route some electricity if it goes between the timbers.
There seems to be a plastic foil on the boards. Any concerns when I cut through that to create a hole?
For the hole, I guess drill 4 times, and with a reciprocating saw cut out the panel?

You can use the existing door as an example.
A few things to pay attention to:

Your hatch must be special kind that is air tight when closed. If it's insulated (styrofoam) it's a bonus. You don't need an external hatch door. The airtight fit ensures that no warm and moist air from the house mixes with cold air in the attic to form condensation and related mold problems at the hatch. That's also what the purpose of the existing vapour barrier is, the plastic foil you mention.
The existing vapour barrier must form a closed seal with the door's trim: it is glued or taped or compressed with a foam lip. Your hardware store can show you which sealing method is best for the hatch you chose. The tape and/or glue are special for vapour seals, so make sure you get the right kind.

To cut the opening you need a drywall saw. No need to drill corners first. The saw has a pointy tip to help initial protrusion. They are cheap manual things and easy to use but messy.
You will use your hatch as the cutting template. Your hatch will likely be fitted from the attic side, protruding down, with the vapour barrier lip pressing against the vapour barrier foil and drywall. Then a trim is applied to sandwich the drywall and rim, and provide a finished look. The trim also conceals the drywall edge at your cut.
For best strength, you may need to build a small a wooden frame to the back of the ceiling drywall. This relieves mechanical stresses from repeated opening and closing and prevents cracking of the drywall. The frame is then attached to both joists. One side of the hatch, usually the hinge side, is screwed into one of the joists. The other 3 sides are screwed into the trim or rim of the hatch. For the frame you'll need 2x2 or 2x3 lumber. You will also screw the ceiling drywall into the frame you built. No need to mud the screw heads if the hatch has a trim that conceals it. So make sure that the frame is positioned tightly behind the trim.
If the door is smaller than 15in you do not need to move the electrical wire. However, make sure that while you are working on the hatch and frame that you do not squeeze/pinch the wire or screw/nail into it. You could move the wire a few inches further up the joist.


How to dispose of a large full length mirror? I have this mirror that I am replacing. This mirror was extremely heavy and fell off the wall one time and the frame is broken. The mirror/glass part is all in good shape. The edges are just sharp and it's heavy so I don't know how to dispose of it. Or where I can take it.

Craigslist (or equivalent) "free mirror, broken frame" with pictures. Or a low price, which sometimes works better than free even without the aspect below...

or

Set beside the street, sign "free" (if that does not work, set a price and hope someone steals it now that it has value, or be pleasantly surprised if someone actually pays the price. Or just start there.)


How to fix a rupturing wall bathroom tile? There are bathroom tiles on the wall (natural stone), the bathroom tends to get pretty humid (pre-code/no ventilation, do our best to keep it low). We are seeing that a few of the bathroom tiles are beginning to flake off--there seems to be a veneer and a dusty material underneath. What's the recommended way to fix this in the short-term? (there's the systemic solution to get rid of the humidity, but during the interim we don't want to inhale this underlying tile dust). Thank you!

It appears that your wall is failing. Whatever those tile are, they weren't intended for bathroom use. You can scrap off the loose particles and then apply a thin layer of caulk or sealer to the area to prevent you from inhaling the dust. How many tiles you're taking about. Other than that, you're going to have to plan on redoing the walls. The tiles will probably continue to fail even if you improve the ventilation.


Convert pair of 3-way switches to a one single-pole with neutral I have a circuit controlled by a pair of 3-way switches wired like this:

where there is 12/3 from the panel to the first switch box with the white not connected.   I'd like to replace the switch in JBox 2 with a remote-controllable single-pole switch that requires neutral.   I have no use for the switch in JBox 1.

Would there be any code problems with removing S1 and connecting the two 12/3 cables together (black:black, white:white, red:red) in JBox 1, installing the switch in JBox 2 (red controlling the load), and connecting white to the neutral bus in the panel?

I can't vouch for code, but that's certainly something I would expect would meet code -- you're just using the first switchbox as an unswitched junction box (which should be legitimate), and Red is being used correctly as second/switched hot.

Then of course your smart switch in the other box connects between black and red, with white used as the neutral for its electronics and otherwise not going anywhere.

Assuming you make the connections properly, and unless I'm missing something....

Quick point: Remember that junction boxes must be accessible for service, so you can't plaster over that repurposed switchbox. You can cover it with a blank plate painted/papered to match the wall, hang art over it, put freestanding furniture in front of it, or a combination of these... but an electrician has to be able to find it and open it up without having to break into the wall.

(Thanks for making me think this through, by the way. I have several two-way circuits, and I too have plans for home automation eventually. Unfortunately I think I have to wait until most of these non-dimmable CFLs burn out and I can replace them with dimmable LEDs.)


Attic Fan Box Vapor Barrier This past weekend I installed a ceiling fan to replace an already existing light fixture. I had to replace the plastic electrical box from when the home was built in 1992.

I am unable to get into the attic for this specific fixture as it's in a spot that I am physically unable to reach due to the layout of my attic and the support beams so I used a retrofit Saf-T Brace rated for ceiling fans.(see below) I'm guessing this box was installed before the drywall was put up because of the location it's at, there really is no way for a person to fit into this small corner of the attic.

When I went to install the brace bar, I realized there is a vapor barrier bubble around the already existing ceiling box with blown in insulation on top of it. It's a 6 mil poly sheet which I am assuming is just stapled and caulked on. I went ahead and cut a small hole on the side to make the brace bar fit through it, secured the bar, installed the box and installed the fan.

I now realize I should have fixed the vapor barrier but since I cannot access it from above - what is the best course of action? I don't really want to have to cut a bigger hole and repatch drywall if I don't have to. Could I use some fire retardant spray foam to seal it up by taking the fan down, removing the box and blowing some in there? Is it even a cause for concern?

A penetration of this barrier is not of concern. Forget about it. It is probably not a vapor barrier, but is there to keep the blown in insulation from working its way into the box and around the box.

In new construction all the boxes are placed on the framing before the drywall is installed.