Shed on grade foundation height limitations I am building a 10x12 shed on a slight slope. I was hoping to do an on grade foundation, but when using a string level, it looks like my slope is about a 2ft difference on its lowest corner.

What are the height limitations of using stacked paver blocks and deck piers with 4x4 post? The plans I have mentioned not to stack more than four 4inch tall blocks as it becomes unstable, but what if it's just one corner? also it didn't specify the height restrictions on the deck pier.

Is there anything wrong with doing a deck pier or a post in ground in the lowest spot, and paver blocks every where else?

How you approach the problem depends on what you propose to use as a foundation for the shed.

Option 1: On-grade paver foundation

Step 1: Build a retaining wall to support a flat grade. The simplest would be a gravity wall: bare wall blocks on a packed gravel base, no mortar. The 4" pavers you mention are not suitable but there are many blocks available for this task. For a small corner wall I suggest buying a few wall blocks at the local chain store. There are nicer blocks available from dedicated stone suppliers but you typically have to buy a full palette. You can also use concrete blocks (CMB) but the wall blocks look nicer and are designed to stack without re-bar or fill. I'm only glossing the surface here. Search for other questions on gravity retaining walls and you will learn more about their construction. The key to their long-term durability is to address any drainage issues so water doesn't build up behind them.

Step 2: Put down an on-grade foundation to support the shed. Sounds like you plan to use 4" tall pavers (e.g. on a sand base). If you want to set the pavers on top of the wall then you need a frame to retain the pavers so they don't slide out. It's probably easier to set the pavers flush with and behind the wall. In this case the shed will sit on the wall, rather than the pavers, in the one corner.

Option 2: Deck foundation

My shed sits on a frame built from pressure-treated 2x6 boards covered with pressure-treated plywood. A deck foundation of this style can be supported by a combination of methods: a continuous gravel base, concrete blocks set on gravel, or deck posts set into the ground with typical deck construction methods. I'm not a fan of the deck post solution because it looks a bit unfinished and tends to create animal habitat (see below). It's better to set the deck on a block retaining wall as above and elsewhere on individual blocks set on a gravel base.

If you intend to install the shed near flush to grade then some of the deck foundation must be buried. Typical pressure-treated 2x6 lumber and plywood is not treated for ground contact. It will not last as long as the shed that sits on it. The paver foundation will.

Building animal habitat

The deck foundation method tends to leave sheltered space under your shed. Once the dust settles your local mammal population is sure to move in. If you're not particularly fond of rodents then you should take steps to deny them this space. With deck construction you can't really fill the space in the corner so fence it off with steel hardware cloth (23 gauge galvanized material with 1/4" holes should do it). If the entire deck is above grade then you'll need to fence it off all around. On end of the fence attaches to the deck. The other end should be buried. The buried bits will rust away but by then hopefully the dirt is packed and the rodents steer clear. I like to cover the buried cloth with gravel as a further deterrence.


Why wouldn't other receptacles work after I changed a receptacle? One of my outlets was getting very hot so I took it apart, cleaned it because it was very very dirty and changed the outlets. It stopped getting hot and the tester said it was correct but now the other outlets do not work at all. Why?

Most likely the outlet was part of a chain of outlets - so there would be at least 2 cables of 3 wires each (hot, neutral and ground).

All of the hots need to be connected together and to the outlet.  Same for the neutral and ground. Often this is done by using the screws on the outlet itself - connecting BOTH hot wires to the two screws for hot.  Only connect one wire per screw.

If you connected it exactly the same way as it was before it should work.  Did you break off the little tabs between the sets of screws?  Were they broken off on the old one?  Make sure they are the same.


Installing Hammock Chair from Ceiling with Metal Joists I’m mounting a hammock chair to my ceiling using 2 eye-bolt plates rated for 160 lbs max load. The plates came with 4 screws meant for wooden joists, but after drilling a pilot hole, I realized the apartment has metal joists.
Since I couldn’t find any info on how to properly mount anything heavy on a metal joist online, I was wondering if anyone here knows what I should do to properly mount the chair? I read about using metal-sheet screws or toggle screws, but since the metal joists are hollow, this doesn’t seem appropriate for a hammock chair (meant for light swinging, as it will be indoors)

I think you probably ought to abandon the project at this point.  Metal joists can be surprisingly light gauge steel.  Sheet metal screws would not be strong and reliable enough for the pullout strength you need, especially holding a moving object.
Toggle bolts would probably be strong enough, I don't see the bolts ripping right out of the sheet metal, but I could see the sheet metal flexing enough to mess up the drywall and possibly deform the joist, which would be a very expensive repair.


Is it OK to drink water from newly-cemented PVC pipes? It has been my habit to use Christy's Red Hot Blue Glue to mend PVC pipe.

I am happy with the performance and the repairs turn out very well.

I also note, with great interest, that it is rated for potable water pipes (NSF pw-G-dwv-sw).

Recently, I constructed a long water conduit with schedule 40 potable water PVC pipe (NSF-61).  The pipe sat, unused, for a month or so, and we used an air compressor to test it (ONLY TO 60 PSI, CALM DOWN ...) and when we let out all the air, it smelled like an open can of PVC solvent.  Very, very strong smell.

OK, no big deal.

So I filled the pipes with water and let it sit for a few days.  Then we drained all of that water out.  Then we filled them with water a second time and let it sit for a few days.

When we ran the spigots to drain this second flush of water, the water had a strong and distinct smell of PVC solvent.  Not terrible, but strong enough to notice.

So my question is this:

On a regular basis plumbers and pump and well guys and other contractors will fix potable water systems with PVC solvent and put those pipes into almost immediate use for drinking water.

Why is this OK ?  If I can dry it out fully and then double flush it (sitting for days each time) and still smell the solvent, that means there is solvent in the water and that means people are drinking it.

Why is this OK ?  Why should I ignore and/or not care about this ?

Thanks.

Your different methods are causing you to notice the smell more than normal.

I'm making a few assumptions, but if you create an airtight PVC pipe, where did you expect the glue to off-gas? It's going to fill the inside of the pipe, especially if left for weeks. The air volume of the inside of the pipe is pretty small, so it's a high concentration. You probably shouldn't be breathing in the test pressure exhaust when you vent it.

Next you said you "flush" it for several days, but filling a pipe with water and letting it sit, then draining it, and doing that twice isn't a flush. Again I'm making assumptions, but that's what it sounds like you did. Run fill pressure water through the pipe for several minutes with it going to drain to actually flush it.

The volume of water sitting in a pipe is miniscule compared to running water.

I don't disagree, PVC glue and primers aren't good for you. We all just "waste" more water than you to rinse the pipe more, so we probably don't notice it.


What type of substrate should I use to install pavers over an existing poured slab patio I'm going to be putting pavers over an old slab patio. The current patio has settled and spalled, so I'm looking to pitch the paver patio in such a way that it drains as the original slabs did. In some places that will mean 2" of substrate while 1/2" in others.

It is surrounded on two sides by brick wall, and a third side by pressure treated wood (the side of a house built on concrete tubes). The fourth side is the down hill side. Since there is something constraining on all sides, do I really have to cement the perimeter pavers down, or can I just install again existing surfaces?

I plan on using polymeric sand for the cracks, but what is the best type of substrate to use under the pavers if they are on top of solid concrete? Should I compact the substrate or not?

Since nobody else it going for this, then I'll give my two cents (based on limited experience, so please, anyone else feel free to chime in).

When it comes to concrete roads, for example, after patching it a few times the road eventually becomes too worn out, and the concrete is rubblized (into crush and run). Then fresh pavement is layed on top. Here's a look at some overlaying options for roads: Concrete Pavement Overlay Design. This isn't a manual and it's not extremely helpful but some of the pictures might help you visualize your own possible solutions.

With that being said, I realize this is just a patio... but the similarities to highways is not so remote that you couldn't glean something from studying how they're done. I think the biggest issue you have to deal with is levelling the area. I'm afraid that I don't really know what's going to work for you. Your idea of whitetopping may be okay... but you also said something about 2 inches... so, I think that the official answer must be that you have to remove the old stuff... it's the only way to be sure it's done correctly... and yes, soil compaction is important. After leveling and compacting the soil you need a full 2" to 3" layer of crush and run before laying down 1" to 2" of sand and new pavers.

Edit- After giving this some thought, my worry would be that the underlying pavers would cause the sand and underlayment to wash out due to non-drainage... so a soil base (which drains) is probably better. Plus, you need room for the crush and run (or gravel), sand, and pavers (but perhaps you already have that depth). The grade should be about 1/4" per 12 ft.

Otherwise if you pour a concrete pad over the old structure, and want to add pavers, then you probably shouldn't use anything beneath the pavers, so that there is nothing to wash away.


Is it a good idea to chisel out the edge of rafters for wires? I am wondering if it is a good idea to chisel out the edge of rafters for wires? We want to floor our garage attic, and there are wires criss-crossing on top of the rafters.

Update: These are regular 2x4 rafters. Or isn't that regular

The top or bottom edges of a beam are the worst places to cut. It is where the most stress occurs. This is one of the reasons why it is best to run wiring/plumbing through holes in the center of your beams. Will it cause a problem? That is impossible to know, unless we also knew how much of a load you would be adding up there, the dimensions of these beams, etc.

While it is very possible there would be no problem, remember that those rafters were put there with no plans for a floor above. The structure may not have been designed to take a load. So if these are 2x4 rafters, on which you will then install a waterbed or a hot tub, expect problems. If you will be just using that floor to store a few light boxes, it probably won't be an issue.

If the floor that you add consists of 4x8 sheets of plywood, they will add considerable stiffness to the floor, but they will also add weight. As an alternative, you might consider adding sleepers on top of the rafters, which would allow you to avoid cutting into these members at all.

Finally, remember to be very careful in nailing/screwing down the new floor. A nail through an electrical line tends to be bad news.


HELP: Supporting Vaulted Ceiling Mid-Beam I'm working on calculating beam sizing to support one end of a mid-beam for a vaulted ceiling.  The room is 16x20, with 4x10 beams spanning the 20' distance (48" O.C.).  There is a mid-beam in place (4x14) spanning the 16' distance.  That load is then transferred to the footing (concrete slab) through an existing wall on each end.  I'm wanting to remove the wall on one end, and supporting this beam is the only structural aspect of this wall.  I'm wanting to put a flush beam in place.
The live load to use is 20psf.  I'm estimating the current roof system (clay tile & t&g) around 15psf.  I have roughly then estimated the load on this flush beam to be approximately 2700lbs.  However, this load is not spread evenly, and is approximately would be entirely in the center.  I'm looking at using a parallam PSL beam, but haven't really decided how to select the proper beam for this application.  Any suggestions or critique of my estimates would be helpful.

I suspect the loading on the new “flush beam” is more than the 2700 lbs. outlined in the question. I calculated 2800 lbs. and that’s without the weight of the upper wall resting on the new beam. (However, I think that would be about 250 lbs. per linear foot on the new beam.)
Depending on the species and grade, a new 4x10 beam 20’ long can support about 2800 lbs. mounted in the middle of the span AND a 4x12 beam 20’ long can support about 3100 lbs. mounted in the middle of the span. (I used a SPF species with a higher than normal grade... like “select structural”.
In addition to holding everything up, you’ll need to hold everything down too, if you live in a high wind area. I’d use Simpson steel connectors between the existing beam and new beam.
Remember, the support posts (and footing) at each end will need to support about 1400 lbs. minimum.
If you’re located in a seismically active area or high wind area, you’ll need to check for shear walls, etc. too.


How to achieve a 1% gradient Currently preparing an area in our garden to lay a paved patio area and pergola (the latter being provided by a professional).

My wife and I need to build a supporting wall around the sides and at the top side (see the photo below).

We have been advised to create a 1% incline on the slabs, so that water can run off when it rains etc.

My question(s) is, how do you measure out/figure out how to do this? Is this a requirement when building a patio area? Is 1% the ideal incline?

You want the grade to be in the width, not the overall length of the patio. The fall should point in the direction away from the home. .01 × (width of the patio in inches) = the height difference. I/E: If the patio is 8' wide, 96 inches x .01 = .96 inches. So the height of one side needs to be one inch higher than the other.

To my knowledge there is no building code for fall requirements on a patio. 1% is a very shallow fall. I would grade it at 2% (1/4" per foot) for a better fall without it looking weird to the eye. 2" over an 8' span isn't going to be very noticeable.


Is a single ductless HVAC system more efficient than two smaller ductless systems? I have an 809 sq ft stand-alone room with concrete slab and block walls that needs to have AC and heat.  We have windows on all sides, 8' ceilings, and live in Florida.  The room will be used as a dog kennel and office.

We're looking at ductless AC units and can't figure out if using one system is as efficient as using a mini-split system.

I would also like to know if using a 24,000 BTU system is sufficient.

I can't say anything about the efficiency difference between single unit or minisplit systems for a single room, but for 809 sq ft, 24000 btu (2 tons of refrigeration) seems like a high estimate based on the information here:

http://www.energystar.gov/?c=roomac.pr_properly_sized

http://www.greenbuildingadvisor.com/blogs/dept/musings/calculating-cooling-loads

http://en.wikipedia.org/wiki/Ton_of_refrigeration

Assuming that your concrete block walls are uninsulated and allow air to move through them (true unless there's insulation and an air barrier you didn't mention), the high estimate is probably reasonable. You will save money and energy in the long run, however, if you insulate and seal the walls and ceiling with advice from an energy efficiency/home performance professional, then install an appropriately-sized system.


Storm doors without glass Do they make storm doors without glass? I need a storm door for insulation and is located on a dark side of my home. It would be added security without glass.

What you are looking for, then, is a security door.  These are essentially storm doors with metal bars that make entry more difficult.  They come in a variety of styles and prices.  If you need the "storm" protection as well, you can get some that include glass or plastic, or you can mount a plastic sheet to the inside.

It will look better than a solid non-transparent metal door, and provide significantly more security than any storm door, without a significant increase in cost.

Also, keep in mind that storm and security doors are relatively simple.  If you cannot find what you want, you can buy the door hardware (hinge, latch, gas spring return), sheet metal, and metal tubing to create your own.  A hacksaw, drill, and screws or rivets, plus metal paint, is all you need. It won't be as secure as a security door, though, unless you buy security door hardware. But if all you're looking for is a storm door without glass, this would provide the same level of security.

Also worth considering is buying a storm door with a plastic window.  Some additional clips, or replacing the window with plastic, will provide slightly more security while maintaining the look of a traditional storm door.


How can I turn a floor lamp, that emits light upward, into a reading light? I want turn this floor lamp into a reading light. I want all light exiting upwards from the lamp shade to point down.
Do I just buy a mirror and put it on top of the lamp shade? Then the mirror can reflect down any upward light. But is this safe? I use a fluorescent light bulb, but it still heats! I don't want a fire hazard.

I would fit a disk of aluminum foil on top, either over or under the shade nut (the nut securing the shade frame to the lamp stud) and resting on the shade support arms. You could also use sheet metal, such as from the bottom of a coffee can.
This disk should not extend all the way out to the shade wall--leave at least 1/2" for ventilation to prevent dangerous heat buildup. Do not use tape or other combustible materials. If you put the disk under the shade nut you could also use a standard or fender washer to prevent damage to the foil.
I'd also use an LED bulb, which emits much less heat than an incandescent bulb.


On heat load calculations My question is simple. Is heat load calculation the same for sizing air conditioners as it is for sizing radiators? I.e if an AC guy gives you the heat loads which lead him to select particular air conditioners can you use those BTU figures for sizing radiators or designing your hot water radiator system (determining flow rates and head etc?)

No.  Heating and cooling loads are dependent on two things: (1) the house dimensions, insulation, windows, etc., and (2) the climate in which it is located.  Some areas have very cold winters and moderate summers, so the heating load will be high but the cooling load quite low.  In another area with moderate winters and hot summers, the opposite will be true.  Both have to be calculated independently.


Does this look structural? My house is 5 years old and is a two story. This is on a ceiling upstairs in a vaulted area of my home. We have an attic but don’t use it for storage or anything. I can tell it’s the drywall but would this possibly be something related to structural or something I can easily fix? I am still under a 10 year structural warranty with the builder, so if it’s that, I want to have them fix it. Thanks.

I don't believe it to be a structural issue but a bad tape joint as @Tester101 mentioned in his comment. There's a slight possibility that this is a byproduct of a small roof leak too, tho not likely in a 5 year old home. Also, as @Tester101 mentioned, it's difficult to say without being able to physically inspect the structure ourselves.

Bubbles in taped joints are caused by not having enough mud behind the joint tape. If I were to fix this, I'd cut out most of that seam and redo it.


Can the neutral and hot be split like this? The picture describes it better than I can, but here is the plan.  Run a circuit off the panel (hot, neutral, ground) into a GFCI.  Off the load side of the GFCI run wires into a light switch box that will control two sets of lights (all lights plugged into outlets).  The hot will be pig tailed in the light switch box to feed both switches, while the neutral passes straight through to the first outlet box.  In this outlet box I will pig tail the neutral (now have two hots and two neutrals in this box).  These two sets of wires will supply two separate sets of lights.
Is this plan valid and safe?

Looks good - you're not switching the neutral, the loads are all in parallel, and the conductors are kept together.


Should double glazing sit evenly in brick to brick window space? I've just had double glazing installed and I'm not entirely happy, but it could be my expectations are set too high.

The picture below shows my new sash window for the front room bay window. This is a brick to brick installation in a Victorian house. From the front of the house the window looks fine, but inside the frame is not lined up evenly. The frame is only visible to the right of the window, the left side of the frame disappears into the wall. I imagined the window would line up in the middle?

Is this kind of issue expected in a 100 year old house which are off square? Or are there ways to make the window hole square so everything fits properly? Have the windows firm measured the window properly?

Probably a case where the window can look good from the outside, or the inside but not both due to the way the house was constructed.

They chose to not make it look like an eyesore from the outside where everyone walking by would notice it.

It's one of the irritating factors of retrofitting something into something that was never built to those dimensions. You would need to hire a finish carpenter to widen the interior opening to give it that aesthetic balance as long as brickwork would allow it.


What can I do about lead paint on fieldstone foundation walls? I have an old field stone basement (1870's) that is crumbling but not just the mortar, the stone itself. We have tuck pointed the mortar areas with some success. Our problem is: the previous owner worked in a shipyard in the 50's and painted some of the walls with blue lead paint. The paint has disintergrated the actual stone into a sandy mess. Any solutions for this problem would be welcome.

The mortar is crumbling because of moisture seeping through the walls from the outside, not from the paint. That is a common problem with fieldstone foundations. See questions about how to remove crumbled mortar and what kind of mortar to use.

I would be very surprised if the fieldstone itself is actually crumbling. If so, you need a structural engineer that specialized in old foundations. Can you please post a picture? (If the system won't let you, upload it to imgur.com or somewhere else, and someone here can edit the picture into your question.)

Working with the crumbled mortar and peeling paint will probably require protective equipment because of the lead paint. See this related question. Bring in a specialist if you're unsure about how to protect yourself.


Chandelier installation and switch wiring Chandelier installed, New Duplex switch--Done!5
--(ignore switch on left for outdoor light)I have four recessed ceiling lights controlled by two three-way switches in my kitchen. I want to add a chandelier and would like to replace one of the three-way switches with a duplex switch(so I don't have to install a larger box) so the chandelier can be turned ON/OFF separately from the existing recessed lights. Can I grab power for the chandelier from the existing three-way switch? How would this be wired? I'm in the USA(NYC).

The key for you will be finding a double switch that has a 3 way and a one way, seeing as you want to eliminate the need for changing out your box - assumption here is that you have an existing installation with drywall already in place.
There is another factor at play though - NEC CODE requirements for how many wires you can put into that existing box. - How much space - you can't just stuff more wires just because you might have a wire hole to feed them into.

However installing a bigger box is really not that hard in this situation as some newer boxes have the box mounting screws internally - not on the outside where it would be difficult to mount in an existing installation (and yes they are screws - quite nifty for about $3.00 USA).

Your wiring might look something like this below.

Below you will find an example of the SMART box by Madison Electric

In your situation this makes perfect sense to use.}
The Tabs for studs - if you don't need / use them they are removable...


How do I remove the rest of this lever-style door handle? I'm trying to remove an old lever-style door handle (with no visible screws) that had a missing latch so was already non-functional. Following online tutorials on how to remove door handles and doorknobs with no visible screws, I made a bunch of progress (even got the plate off, revealing two screws beneath, which I also removed) but cannot, for the life of me, figure out how to remove the rest of the remaining structure.

Photos from different angles (both inside and outside) available here: https://imgur.com/a/2J70dMm

I suspect there's some kind of mechanism that I need to press/engage which will allow me to pull these remaining cylinders and the remaining inner-plate (?) out.

Thanks for your guidance!

It looks like there is a threaded collar screwing through from one side to the other. I think if you use a small screwdriver / punch to undo it (as arrowed), this will release the two halves:


What is the best way to tell a water stain on a drywall is wet We had a leak in the roof a while ago that caused water stains on the wall. The leak should be fixed now, but we wanted to wait a bit before painting the wall until we are sure that there is no more water leaking in. I feel that it is now really hard to tell if the wall is wet where the old stain is, or just cold.

What is the best way to tell if the drywall is actually moist or if it is dry. Preferably without buying any moisture meter or so.

Thanks
Simon

Press a paper towel firmly against the wall and hold it there for a minute.  Then feel the paper towel for see if you sense dampness in the paper towel.

Hand the paper towel to somebody with neutral hands, since yours may now be cool, to sense if the paper towel is damp.


What are the differences between wood and composite shoe molding? I'm about to install shoe molding all over my house. I'm deciding between composite (I think it's PVC) and wood. They are quite similar in price. How do these 2 materials compare in terms of:

durability
paintability
cutability
prone to splitting by nails
anything else I'm overlooking

I would go with the wood. It will paint & caulk better. Some of the PVC stuff doesn't cut well on a chop box, has a tendency to break and may crack with larger nails. PVC just looks cheap when its up, you can tell its plastic.

If the composite is MDF, I would buy that over wood. MDF is cheaper, and usualy straighter pieces. It also paints nicely. The only time I might choose wood over MDF is if I were staining the molding.


How to seal marble tile mixed with glass? I recently put up a tile backsplash with mosaic marble and glass tiles.  I'm preparing to apply sealer to the stone before I start grouting.  It's several hundred 1/2" x 2" to 7" mixed in a random pattern.  Here's a photo:

It's going to be nearly impossible to avoid all the glass tiles, but both the sealer and tile instructions clearly state to keep sealer away from glass - any tips on how I can apply this to the stone tiles without mucking up the glass?  Alternatively, are there any stone sealer products out there that don't have the glass restriction?

Alternative idea.

Test the sealer on a piece of left over tile.

Let the sealer get onto the glass and wipe it up shortly thereafter.

Compare the before/after -- if you see no notable damage, just put the stuff on and have someone clean up the glass right behind you.


Grounding Requirements for same structure subpanel I understand that unless a 250.32(B) (NEC 2014) applies, a separate ground wire should run from the main to a subpanel where the service is in a separate structure.

Still confused however about NEC grounding requirements for the same structure. I am replacing a subpanel  and moving the location from the Kitchen to the garage, about 3 feet. The main is 200 amp (grounded and bonded) service and the subpanel 125 with a 3 wire #2 feeder between the two and EMT the entire way in the slab. All 11 EMT runs to the house, as well as the feeder were buried in the slab until an archeological dig to extricate and extend the EMT to the new subpanel. Each of the EMT runs and the feeder were attached to the wire mesh in the concrete by small wire (14 guage or less) within about 6 feet of the panel. I plan to replace this. Not sure if this was for grounding, or just to hold the EMT in place when the slab was poured.

Does the NEC require a separate grounding wire back to the main in this case and/or a separate ground rod by the subpanel?

If not, would a separate grounding rod at the subpanel be a good idea. Not anxious to try and run a separate ground back to the main.

Thank you in advance for any help.

Your ground path is through the EMT conduit. It needs a proper connection to the main panel ground and to the sub panel ground. You could use grounding bushings, but standard EMT connectors meet code.

The “connections” to the concrete reinforcing are not part of a normal grounding or bonding approach. This kind of bond is only used at the service entrance and uses more substantial wire.

One concern with your installation is that EMT conduit can corrode in buried or embedded installations. I have seen conduit rusted completely away after four or five decades of service. This can result in high ground impedance and non-tripping breakers. If you have this problem you should run a new feeder with a proper ground connection. Do not drive a separate ground rod at the subpanel. The ground connection belongs at the service to avoid ground loops and to ensure over current protective devices work properly.


Will heat set off a smoke detector placed in an attic? A heating furnace is in a partially floored attic. used for storage only  We have
placed a smoke detector above the furnace and wonder if the heat in the summer would
set it off.

Heat will not set off a smoke detector. Heat will set off a heat detector, but most heat detectors would not be set off by the temperatures in an attic (and if one is, if probably means the attic could stand some ventilation upgrades.) A heat detector is commonly employed in areas where some minor smoke might be expected but fire is still a concern (such as near the stove in a kitchen, or directly over an oil furnace or boiler, which can smoke a bit when being serviced - much more so than a gas furnace or boiler.)

A photo-electric smoke detector can be set off by dust (and if poorly designed, by spiders getting in the beam - a better designed one will exclude spiders from that area, but I have certainly seen false alarms that were blamed on spiders in the unit.) However, if nothing is stirring up dust, that is relatively unlikely.


How can I waterproof wall sheathing along concrete steps? kick board with nothing between it and concrete is rotting. What can I do?

Well, you aren't going to keep all the water out. The builder should've applied a water barrier before pouring the concrete. You'll have to decide whether the sheathing is degraded enough that you need to replace it. Here's what I'd do (after letting everything dry out well):

Procure some flexible waterproof membrane such as ice and water shield or window flashing tape. It should be gummy on the back side so it bonds to itself and seals around fasteners.
Apply it to the sheathing along the concrete, tight to the joint. Use staples along the top and wherever needed to hold it securely to the sheathing. It should run up the wall at least 6" or whatever space is available.
Caulk the membrane/concrete joint with a high-quality caulk. Silicone is ok. Latex is not. Urethane is better. Create a substantial, coved bead, but try to keep it small enough that it'll be hidden under the j-channel. Use masking tape on the concrete 1/2" away from the sheathing if you like.
Reinstall your siding.


Subpanel wire size questions I am installing a subpanel in an out building that will be fed from a 50 amp subpanel in another out building ( going all the way to the main box is not an option). I only need 30 amps in the new bulding and I am using #6 wire for the 80' run between buildings. After the new subpanel and a 30 amp breaker will be another 55' run to a 30amp plug for a RV hookup. According to the interwebs I can use a #10 wire for that run. My question is when I'm calculating wire size is the length of the run considered from the new breaker to the outlet or do I need to use the distance from the original subpanel in the other building ? My thinking is I should use #6 all the way to the outlet as well.

You have 2 completely different questions in two completely different scopes. Don't confuse them.  You must consider and answer each individually, and use the higher of the two answers.

Given the receptacle you want to use, which defines the breaker size, what is the minimum wire size you must use to keep from cooking the wire?   A 30TT or 14-30 requires a 30A breaker, and the answer is "10 AWG wire".
Given the current you realistically expect to draw, actually, how much voltage drop do you feel will be acceptable to you?   This is more complicated, starting with the "current draw, actually".  It depends dramatically on what appliances are installed in your RV, which appliances you actually do use, and how much current those draw. Which you need to survey.

Remember -- having a 30A plug does not mean the RV draws 30A.  It means that is the standard socket at RV parks, because some other RVs draw 30A.

Continuing part 2, you need to figure out the voltage drop you find acceptable under your practical load(s).  I for one don't have a problem with a 5-6% drop, but then, I don't feed my family by upselling you into thicker wire.  Those who do, say 3% is max.   3% is not mandatory, it boils down to what you find acceptable.   The voltage drop cannot damage your wire, the required breaker in step 1 guarantees that.

As an example, let's say your practical load is 10A most of the time and you'd like to have a 3% drop then; or 20A in extreme circumstances and you don't mind a 6% drop then.

Plug those into a voltage-drop calculator, and there you go.  (only consider the distance from the last subpanel to the RV).

Now, take the largest (smallest numerically) in step 1 (10AWG) and step 2 (in my example 12AWG).  You must use at least 10AWG.

If you did the numbers again with 3% at 24A (the highest you are likely to draw continuously), I get 10 AWG.

If you want to for thicker wire nonetheless, that's between you and your wallet.

Now consider the new AA-8000 aluminum alloy wire.  The ooga-booga about it never applied to AA-8000, nor to large conductors.   At those large sizes with lots of metal content, it is far cheaper, and bonds better to large lugs, which are made of aluminum.

Starting at 6 AWG Cu, I start pricing it both ways - you need to run the numbers and typically go up a wire size i.e. 4 AWG Al.  For the cost, you could even upsize the AL and reduce your voltage drop further.

If you upsize the feed to a subpanel, you can upsize the supply breaker.  If you upsize the feed to a receptacle, you must use the breaker the receptacle requires.


How to insulate slab that's been extended? I bought a house built on a concrete slab on grade. It's an older house, so no part of the slab was insulated. At some point in the past, previous owners decided to pour concrete around the entire perimeter of the house, effectively increasing the size of the foundation slab so that it protrudes two or three feet out beyond the walls (this appears to have been done at least partially for termite control).

My problem concerns how to insulate the exterior of the slab. Obviously I would have to dig to expose the slab edge that I could insulate, but would this even be possible given that the slab has effectively been extended outwards? Even if I insulated the perimeter of the extended slab with foam boards or a 12" perlite-filled trench or something, the top of it (that you can walk around the house on) will still be exposed to the exterior temperature.

Should I just cover the exposed slab surface on the floor with polyiso (R-7) foam insulation boards instead? The final floor coverings will be mostly wood, with some tile and carpet.

The walls are already insulated to about R-10 or so.

Insulating out 2-3 feet won't make sense, as particularly on high desert nights far too much will be sucked right out of the extended slab to the air.

Removing the slab extension should be explored. It has no valid termite purpose, other than to provide good habitat and a staging point for termites looking to crawl up one of the inevitable cracks.  French drains on the other hand help keep the soil or sandy soil dry, reducing termite habitat.

A local insulation expert will have to comment on the cost/benefit of traditional slab sidewall insulation: have them show you before & after energy statements as proof their products have a positive payback in your microclimate.

--

Floor coverings are fine, but in your climate you have extreme desert temperature swings, and the thermal mass of the slab is helpful in both heating and cooling seasons.


How do weather conditions affect pouring a concrete foundation? I'd like to understand how weather conditions affect pouring a concrete foundation.

Are there concerns about pouring a foundation during cold, snowy, rainy, or otherwise inclement weather?  Is it safe to do so, and can it affect the longevity of the concrete?  Are there other considerations?  Extra cost?

What precautions should I request in a contract to ensure the foundation is poured effectively?  Are there tests that can be performed prior to pouring and/or temperature limits that should be maintained?

If it's too wet and water starts to accumulate in the foundation, you can end up with weakened concrete.

One of the key metrics for a concrete mix is the free water to cement ratio. If the water content is too low, you struggle to get it to compact properly , resulting in air voids, and weak concrete. If the water content is too high, the water can leave pores in the concrete, which also reduces the strength of the concrete.

If the temperature is low, the hydration reaction slows down. Further, if the temperature is too low, the water can freeze, which means that it is not available to hydrate the cement, again affecting the strength of the concrete.


Loose thread in standing lamp between base and rod My wife just bought a lamp at Target, the kind you have to self assemble the rod from 4 hollow pipes and a base, where the electrical wire is already threaded through all of them.  Each of the 4 sections screws into the one below it, and finally the bottom one screws into the base.

The rod sections / pipes screw into each other perfectly and tighten nicely.

The last one that tightens into the base is a bit too large, you can screw it on all the way but then the whole thing wobbles, if I try to tighten it anymore it keeps turning freely. After unscrewing it and re-screwing it back a few times I realized it is so big it literally can be pushed down instead of screwed in.

This thread has some interesting suggestions:
What can I use as a thread "tightener" compound for a free-running bolt?

I tried plumbers threading tape and it got squeezed out and shredded and didn't really make a difference. I tried Scotch tape and had the same results. (I do think I may have put too much of both, I probably went around 7 or 8 times).

Finally I tried dental floss, which helped some - its a bit tighter now and I just left it as is.

Any other suggestions?

Since I saw this question on other threads: The base itself has an extruding nub with threads that the bottom section covers and screws over. Both of them have threads. Both of them are hollow and the electrical wire goes through it all.

That's a common failure mode for those lamps; the threads are fairly shallow and prone to stripping out. Though if it happens immediately, rather than after a few years of use, I would definitely return it for refund and/or replacement.

If it fails after the warranty has expired:

It is possible to kluge the connection by wrapping the threat in teflon plumber's tape; enough layers will tighten the connection so the remaining threads can engage. This, too, tends to eventually fail, but you may get several more years of use out of the lamp.

Theoretically you could sweat-solder the mechanical connection, but you'd probably ruin the lamp's finish. Obviously you'd want to remove and reinstall the wiring so its insulation doesn't melt during thd attempt to solder it. And I'm not sure what solders would be compatible with the lamp's metal.

Realistically, most of us consider these lamps disposable. I just discarded one myself, after scavenging some parts that I'm planning to reuse.


Hanging 20" x 16" glass pane I have a 20" x 16" glass pane (that is somewhere near a 1/4" thick) that needs hanging on a wall. The glass pane is actually a holographic image.

I remember seeing a compression/spring mechanism for hanging non-framed pictures that had clasps for each of the 4 sides of the shape and an X spring design to keep pressure even while providing a hookable mechanism some years ago but can't seem to find anything similar in a web search now.

What is the recommended way of hanging something of this size and weight these days?

The item you remember is called Swiss frame clips and still commonly available.

The other usual option is a standard method of attaching large glass objects to walls - mirror clips. Fancy or crude.


How to interconnect Kidde smoke/co combo detectors Mod# KN-cope_IC with Edwards Heat detectors Mod# CR-135-2 using relay SM120X How do you wire the above units so the smoke/co detectors will all ring when heat detectors are activated. The heat detectors are a two wire hook-up. Existing wiring to heat detectors is existing and in wall. Hard to change to 3-wire.

You'll need to run a /3 cable from the smoke alarm run to wherever you want the relay to go, and a /2 cable from the heat detectors to the relay location, which will need a box at it (a simple 4" square box will do if you aren't putting the relay at a smoke or heat detector location).

Once that is done, connect one wire of the /2 cable to the red wire in the /3 cable, black and white on the relay module to the matching wires on the /3 cable, the grey wire on the module to the other wire in the /2 cable, and all grounds together and to the box the relay is in, if it's a metal box that is.

This way, the 9V supply from the SM120X will be connected to the red interconnect wire when the heat detectors close, causing the smoke alarms to sound.  Note that the heat detectors will only work if there is 120V AC power available to the house, even if the smoke detectors themselves have battery backup.  (The SM120X doesn't provide a backup battery for its 9V supply, in other words.)


My apartment door unlocked by itself. Can anyone offer an explanation please? My apartment door unlocked itself.....a wood kind of one with a round door handle that key goes into. I shook it when I was leaving to make sure it was locked then I came home to find it unlocked....twice. Does anyone please have an explanation for how this could have happened?

Either your door lock is defective, or someone is unlocking the door while you are gone (someone with the key, like your landlord, or someone is picking it open).


Ceiling Light Installation: Junction Box or SLIM Led Driver Differences What are the advantages/disadvantages between using a Junction Box Ceiling Light Installation or a Slim LED Driver box installation?
My ceiling has space to incorporate either option.
I am wondering what the best option is, is the industry going towards more LED Driver box ?
The Slim LEDs come with their own junction box.
Examples:
LED Round Color Select-able Flat Panel Recessed Trim
Ultra Slim 6 in. Canless Color Selectable CCT Integrated LED Recessed Light Trim Downlight 900 Lumens Dimmable
Slim LED with Driver Box:
Installation Video: https://www.youtube.com/watch?v=w4fHshRd3g0

Junction box Install

searching to understand comparison, vs. for new house

In both cases a box is required. The advantage today is the slim may be cheaper, but in the future you may be tied to a slim box.  This could become a problem when all the mfg’s are only making replacement modules for full sized boxes because of the millions or hundred of millions of full sized boxes currently in use. How many slim boxes were ever installed?
The other consideration is that if other wires are in the box to connect to other lights, there is a minimum number of cubic inches required to accommodate those wires, so in this case, a larger size may be required today and provides more options when this light fails (LED’s rarely fail but the electronics driving them sure do).


How do I repair screw holes in a brick wall? I have screw holes which were put in to support a curtain rail. The curtain's been pulled out a few times by accident, and now the screw holes are crumbling and I don't know how to repair that portion of the wall.

I want to get it firm again, then re-drill and put the rail back up. It's a plastered brick wall.

What should I do to repair the crumbling holes in the wall caused by the dislodged screws?

There are epoxy repair systems for wood. It should work here too. Once it hardens, the epoxy is a tough, sandable, paintable medium that can de drilled. Make sure it keys properly into the hole, so that it does not just pull free under load. This may involve an undercut if necessary.

In fact, I just checked, and there are epoxies available specifically for masonry repair too, but the wood product should be sufficient here, and is easily found in most home stores.

An alternative might be to add a flat wood molding behind the entire length of rod. 3/8 of an inch thick should be sufficient. Paint to match the wall. Now anchor the curtain rod to the wood, using expanding drywall anchors, if necessary.


Is it safe to use a drill bit with a half broken tip? I broke the tip of the masonry drill bit. The tip looks like this now. Half of it is missing, and it seems that the tip itself moved slightly towards the center (since at the bottom, it is parallel to the shaft).

Is it still safe to use the drill bit, or is there a risk that the remaining part of the tip would detach when the drill is turned on?

The fact that part of the bit has broken off does lead one to believe the rest of it may be in danger of disintegrating during use with the potential for bits of metal to go flying in unexpected directions.
Also, the fact that the point appears to be off-center means that you're going to have a hard time getting the bit centered where you want the hole to be and keeping it centered while drilling.
While masonry bits may not be the cheapest bit in the aisle, it seems that now would be a sensible time to replace this one.


Pumping water using a small electric pump, does it need to be potable? I am doing a little DIY project where I need to pump 4-5 gallons of water that is less than 100'.  I need the pump to be able to run dry as it starts to pull the water, then it would pump the water.

Does this need to be a potable pump?  Non-potable pumps are much cheaper and I will only be running the pump like twice a month for 20 minutes at a time.

Potable example: http://www.attwoodmarine.com/store/product/Potable-Water-Pump

non-potable example, a little pond pump from Home Depot.

With it being hard plastic, I just can't see how it could have an issue.  The water does need to be drinkable..

If you will be drinking the water, you need a potable water pump. "Potable" means "safe to drink."  No matter what, if needs to be able to start dry, you need a "self-priming" pump.


What do you call those little round rubber things in door jambs? What do you call those little round rubber things in door jambs?
Those things are used to prevent the door from hitting the jamb. It's kind of like a little round bumper.

I don't know if this is the "official" name, but if you search online for "Cabinet Bumper", I believe you will find exactly the item you are looking for. So it could be assumed that is what they are called - you already answered your own question.
Some alternative names I saw:

Surface Bumper
Bumper Pad


Bleeding an old baseboard radiator Background: Third floor radiators are cold. Pressure hovering around 11. Went to bleed everything and got stuck.
I have these old things on the first floor:

I can't find a traditional valve, all I have are these:

The top cap twists off, and water will pop out if you press down. Is that the valve? Or do I have to take off the front plate?

That is an automatic bleeder valve - they are subject to becoming less automatic to non-functional over time, and yours are well into the "heavily corroded old age" stage of their lives, or at least the one in the picture is.
If you don't get air when you actuate the valve, this location is bled.
When working properly, any air is collected in the chamber, and once enough air has collected a float drops and causes the air to be vented. The valve cap is normally left somewhat loose so that air can vent, until they start leaking and you have to disable the automatic part of their function by cranking the valve cap down until it seals (normally has a rubber seal inside the cap for that purpose.)
They still work as an air collection point that way, but you have to unscrew the cap and let the air out, then reseal it so they don't leak water at that point.
Here is a cutaway view (from caleffi.com, never heard of them, no affiliation) showing their version of the mechanism.


Foundation repair: time frame Sorry – this is long.  I own an older home (1920s construction) that I do know has foundation problems.  I am not asking for a diagnosis of those problems per se.  For data purposes, the problems are:

South basement wall (partial basement, the rest is crawlspace or less - see below) has bowed and cracked due to hydrostatic pressure from really idiotically bad draining for several years before I bought it.  The house at one point had definely settled on this wall.  Before I knew about the bowed and cracked wall (it was hidden by drywall in the basement), I repaired the drywall problems I could see.  Over the past year, I have observed at two windows above this wall very short (3-4") hairline cracks, but no other evidence of movement.  All windows still open and close easily, as do the doors in this part of the house.
The east foundation crawl space wall, for a span of about 20 feet, has suffered cracking, and has bowed in some.  This wall is a very shallow foundation, and will mostly likely need to be replaced, as there simply isn't much for a pier to grab onto.  In the bath by this space, I have noted slight shift issues, defined as an apparent 2 mm shift in the top of the tub surround relative to the paint line on the wall, and stress marks in corner drywall tape (i.e bubbles and apparent minor vertical movement).  The door to the bath is still square (or as square as it ever was - opens and closes but is a bit stiff in upper corner - no change in one year of use).  The space under the house in this area is only about 12 inches, so calling it a crawl space is generous.  I have temporarily installed braces under two floor beams and one section where the foundation was cut away for crawl space access.  These braces are temporary, absolutely, but with them in place one crack under a window closed up up, and a door that was slightly sticking (i.e. A bit stiff to open, but did open and close) is now much easier to open.
A cracked spot about 8 feet from the NW corner of the house, that unfortunately is near a pillar holding a ceiling crossbeam for the great room of the house.

I have brought out a foundation repair company engineer.  He has described some repairs which seem plausible, and did not seem overly concerned about the state of the house.  He suggested several things I could do to further improve drainage and protect the foundation along with repairs. These drainage improvements are ongoing right now.  However, I am unable to arrange the financing I would need right now to make the repairs – it simply is not possible until at least mid autumn, and probably not until late spring.

With all that data, now to the questions: given all above, and diligent efforts to protect and monitor my situation, is it plausible to get between 6 and 10 months further down the road before initiating repairs?  I have marked and measured existing cracks and am logging them and photographing them to monitor any changes.  Beyond watching for new cracks or shifts in existing ones, what else should I watch for that would indicate somehow finding a way to accelerate repairs?

If it were me, I'd stick with your drainage improvements, monitor, and save pennies to fix this for real.  1920s-and-older construction is often significantly overbuilt (I've owned 5 so far, so take the sample for what it's worth statistically!) and can take a lot of abuse.  You do want to fix this, but your time frame seems to be in months, not years.  If you see shifting measured in millimetres, given the tectonic rates at which houses shift, you're probably ok for the next couple years.  If your monitors show issues, move fast.

All of that is provided that you are not talking about significant (recent or contemplated) excavation, changes in the surrounding water behaviour (did you remove any trees?), and that you are getting the water far away from the foundation.  Stabilize all that, and I bet you'll be ok for the next few years, assuming you have no seismic problems locally.

Also, of course, this advice is worth what you paid me for it; if you'd paid me, I would't give it. :)  But that's what I'd do.


How to replace a single light switch with an electric dimmer switch This is a very similar question to one I asked yesterday, which Ryan Walkowski kindly helped out with.

This time, I'm looking for a some assistance in fitting a a single electric dimmer unit.

I am trying to replace my existing light switch with a LightWaveRF dimmer but am also have an extractor fan which powers on which this switch is on.

I took a guess but is anybody able to confirm the correct wiring (I'm in the UK) for such a setup?

Here are the old and new switches:

Technically that is the wrong switch for what its doing. That switch is designed to isolate both the incoming live and neutral. However i can see it has been jerry rigged per se as the incoming live and neutral at the top has been bridged to serve another purpose. You are going to have an issue with it. Are you able to indicate which of those cables goes where?


Recommendation for home automation solution I have an buried driveway sensor - the kind with the cable that runs back to the house to a control unit - and I've been using an X10 Universal Module wired up to that and plugged in to communicate to chime units in the home.  We've had this system for nearly 20 years and it has generally worked OK but the X10 modules have been failing and I feel like I'd like to upgrade things.

The existing driveway sensor still works great so I don't see any reason to change that out at this point.  But I'd like to use a newer wireless technology (or I'm also not opposed to something better than X10 for a powerline solution) to accomplish (at least) the same job as my existing setup did.

The driveway sensor system is a Mier Driveway Alert system.  It has Input -- 120 VAC, 50-60Hz, 3.6 WattsOutput -- 24 VDC at 100 Milliamps or: Dry Contact Relay - 24V/1AMP Maximum.

I see a lot of Z-Wave and Zigbee and Thread and other modules out there but have not seen a similar module to the X10 Universal module - something to take the wired signal from the driveway unit convert it into the appropriate wireless setup.  It is very possible I've just overlooked this.

Do you have suggestions for a solution?  I'm mainly interested in a straightforward solution that works.

My sensor unit is about 30' from the house and, ideally, I'd like to be able to put a few chimes around the home and maybe have an option to send an alert to my phone.

Thoughts?

Your description of the system mentions a Dry Contact Sensor. There are several types on the market. Simply wire these into your existing setup as either Normally Open or Normally Closed. They are easy to set up and some come with free wi-fi phone notifications when triggered.

Here is a Mier Installation Manual that shows wiring possibilities for NO and NC accessories that can help you along.


What type of glass to use for shelves? I have a cupboard that has glass items in it:

I'm thinking it would be really cool if these were glass shelves.
Is there a special type of glass for this?  I'm thinking it's got to have some kind of rounded edge on it so nobody gets cut, but then is there some kind of glass that is less likely to get scratched as items are slid on & off the shelves?

Regardless of color choice, make sure you get tempered safety glass.


alternative to packaged unit downstairs House built in 1922. Never had central air. Heated with hot water boiler and rads. 2 stories, 1569 sq ft. Salesman recommended split sys upstairs and packaged sys down. Only appx 22 inch clearance in crawl. Unable to put in ducts downstairs, so recommended ductless mini splits.(unacceptable to me). Is there an alternative?

Mini-splits have many advantages, so tossing them out wholesale is a somewhat puzzling response to a house with limited options for running ducts. If you don't like beige plastic boxes (who does, really?) there are several versions that are made to be visually unobtrusive, with the inside unit concealed in a picture frame, or a small inside unit that can be tucked in a ceiling, wall cavity or between the floor joists, either with a faceplate that is the register, or short ducts (a ducted mini-split, as opposed to ductless.)


Can I use the area above my garage for an extra room? I want to use a 8 x 20 space above garage for an extra room (Load Bearing). It has two 2 x 10’s sister’d together spanning of 20 feet and 16 inches apart with no center support.

Can I make this set up into a room as described? What will be the path I need to take to make a (load Bearing) room. Will the set up I have meet the load requirements?

The short answer is, you'll have to contact an engineer. Only an engineer will be able to tell you if the structure is adequate, and/or what you have to do to make it so.

If this is going to be a habitable room, you'll have to make sure it meets all the building requirements in your area. So you might have more to be concerned with, than just the floor.


Dye laminate which lost its color because of detergent A bottle of detergent for toilets leaked on my laminate for 3 days.
The laminate became filled with it on a small area (less than 10cm²).
The floor lost its colors and it slightly tinted in blue (the detergent is blue).

What should I do to fix it?
Thanks

most of the blue dyes in toilet cleaners are copper sulphate pentahydrate.  flushing the stain with dilute muriatic acid should re-dissolve it.  be gentle, wear gloves and a respirator, and keep the area small.  flush with water and baking soda immediately after you notice the stain is gone to stop the reaction from progressing too far.  seal afterwards with wax, acrylic, urethane, etc.


Water dripping out of small pvc pipe in soffit of house Yesterday was an extremely hot day here in SoCal with temperatures around 100F.
The AC unit had been turned off during the daytime and at nighttime we turned it on to cool down the house.

A few hours later I noticed water dripping down from the soffit right above the upstairs bedroom window on the front side of the house (two story apartment). I don't remember seeing that happen before so I took a closer look and pointed a flashlight at the window where the water was coming from. I noticed a little pvc pipe sticking out of the soffit and that's where the water was dripping out of.

I did some Googling and found some info saying that it could be the secondary or emergency drain of the AC unit, which is where the condensed water goes to when the main drain is clogged. It also said that it's usually in an obvious location so you notice when there's something wrong.
I also saw some contrary info saying that it's normal for small amounts of water to come out but that seems to be quite subjective to me.

I turned off the AC after finding out about this, because I don't want any water damage inside of the house. This morning I turned it back on to see if more water will come out, but so far no water.

The actual AC unit is outside on the other side of the house in the back patio.

I've made an appointment with an HVAC company to check this out, but because of the heatwave HVAC companies are completely booked up and I'm going to have to wait for two weeks.

I'm posting here because I would like to find out if anyone can confirm that this is indeed the emergency drain and if it's still safe to use the AC without risking water damage. Could the dripping be caused by the extreme temperatures yesterday while the AC unit had been turned off during the daytime?

Two weeks with no AC is a long time with temperatures like this, so hopefully someone can give me some insight.

This is an image of the pvc pipe:

I'd suspect it's a secondary drain. It's possible that the main drain was simply overwhelmed, and the condensate level backed up to the point of the secondary drain.  If it was really humid, a large volume of water could have been removed from the air.  If the main drain is slow, it could have simply not been able to keep up.

Without inspecting the system, it's impossible to say for sure what's going on. If you can follow the pipe back to the air handler, you could confirm that it's the secondary drain. You may also be able to determine if the main line is clogged, and possibly fix it.

If you go poking around, you could post some photos here, and somebody might be able to offer more help.

From the looks of the pipe, it doesn't look like it would cause any water damage.  But I can't see if it's dripping on anything important.


Can I use an air to air heat exchanger to fix a radon problem? I tested my basement for radon, and found that it was twice the allowable level (8 pCi/L).  Can I use an air-to-air heat exchanger to reduce the radon level, and to pump fresh clean air into my basement and the rest of the house?  How effective are these compared to conventional radon reduction systems?

My house was built in 1915, and the basement floor was repoured and the walls resurfaced a few years ago - I don't think that I can reduce the radon by sealing cracks.

In addition to reducing radon, the air-to-air heat exchanger would also reduced other pollutants that are generated inside the house - I don't understand why it isn't used more instead of conventional radon removal techniques.

You are much better off preventing it from entering in the first place. But once it does enter, ventilation is the only way to reduce the levels. How effective this would be depends on the exchange volume. You would be committed to running this exchanger 24/7 for ever. Replacement costs would be much higher than the typical radon fan. Anything running 24/7 will wear out eventually.

And there is still a significant energy loss running like that at decent volume. They are no where near 100% efficient.

If the floor was poured over a layer of gravel, a retrofit sub slab extraction system would likely be successful. If it was poured on compacted earth, a successful system is much less likely. You are right, just sealing cracks without any other remediation would not be very successful.

Testing for adequate sub slab permeability isn't too involved, drill a few well spaced holes through the slab and see if sucking air out of one hole draws air into the others.


Sub base for slabbed area with cabin on it I'm looking at slabbing an area of my garden and then sticking a cabin on top.

I have a large amount of old slabs and some other rubble/hardcore. If i smash up all the old slabs, will this be a suitable sub base for the slabs?

Thanks

The best base has a range of aggregate sizes so that they all fit together, lock in place and fill all the voids tight. Therefore the answer is dependent on the size of the pieces you break the old slab into. The smaller, and closer in size to the rest of the fill is best. Or have adequate space between larger pieces so that you can be sure to fill all the voids very tight or over time the soil and other aggregate will migrate to the voids and settlement will occur.


What are the relationships between ground and arc protection in breakers and in outlets? I'm wondering how combos of AFCI & GFCI protection on breakers and outlets affect overall circuit safety & performance. What I mean is, how do different combinations of GFCI and/or AFCI protection relate when applied on a circuit breaker and/or an outlet?

Some combinations I've heard/thought of already are as follows, but I'm not sure how the different protection methods and redundancy between the same kinds of protection can help or hurt one another. The items in bold are the ones in particular I'd like to learn more about. How does the combination of safety devices interact with one another? Assume the circuit is grounded (e.g. connected via NM 14/2 with ground wire hooked up properly throughout.

regular breaker with overcurrent protection + regular outlet
reg breaker + GFCI outlet
GFCI breaker + GFCI outlet
AFCI breaker + GFCI outlet
AFCI & GFCI combo breaker + GFCI outlet
AFCI & GFCI combo breaker + regular outlet

Definitions

GFCI is intended to protect humans against severe shock or electrocution.

AFCI protects structures (and their human occupants) against fire.

AFCI detects if there is an open arc on a circuit and de-energizes the circuit. Electrical arcs can start fires easily if they hit the wrong material.

GFCI detects a current differential on the "hot" and "neutral" wires. In a functioning circuit, both wires carry exactly the same current. If there is a difference in current between the wires, it means current is leaking somewhere else. The "somewhere else" could be through you and cause injury or death.

GFCI breaker + GFCI outlet

This is pointless, or at least overkill. GFCI's can fail, but the electrical code doesn't require you to wire up redundant GFCI's in series. The GFCI breaker protects the entire branch circuit. Likewise, one GFCI receptacle on a branch circuit can protect all of the downstream receptacles if wired correctly.

Do test your GFCI's from time to time to ensure that they are still functioning correctly.

AFCI breaker + GFCI outlet

This will protect against fire (the AFCI will trip if there is an open arc), and it will also protect against severe human shock/electrocution. This is a fine combination and combines positive attributes of both types of protection.

AFCI & GFCI combo breaker + GFCI outlet

As in the GFCI breaker/GFCI outlet scenario, the GFCI outlet is redundant and thus unnecessary to meet code requirements.

EDIT

Tester01 makes a good point about the possibility of getting shocked before a GFCI trips. You may get bit, but a properly functioning GFCI should trip within 25ms (0.025 seconds), at a voltage differential between 4 mA to 6 mA. Most people can feel electric shock starting around 1 mA, and it's a relatively mild to uncomfortable sensation up to 10 mA, after which it becomes painful. 10 mA is also the threshold where involuntary muscular contractions become strong enough that you may not be able to let go of the thing that is shocking you, and the current starts to become lethal between 75 mA where breathing becomes so difficult that it stops, and 200 mA. In any event, a properly-functioning GFCI should cut the current completely before you are permanently damaged.


advice on sealing crawlspace vents to outside air My house was built in 1950, and in my crawlspace, I have vents covered with mesh wire that circulate air to the outside.

I've been reading online that its now best practice to seal the vents in the winter, and open them up in the summer, but I wanted to get peoples feedback on this, given the environment my house resides in.

I live in a typical Northern California climate that experiences moderate weather all year around. In the winter, occasional rain storms, with the temperature approaching, but rarely hitting freezing, and in the summer, temperatures between 80-90, rarely hitting the 100s.

Throughout the year, unless its raining or foggy, humidity is never very high.

In addition, I have a sump pump in my crawlspace, as I experience a good rush of water from the hill I'm on during a downpour.  The crawlspace is rat-proofed, and over time, I do need to epoxy paint over the cracks that develop that leak water to the unfinished floor (its just epoxyed-over concrete) at the end of each rainy season.  This water that may escape through the cracks that develop finds its way to a drain in the concrete floor that drains to the same reservoir that the sump-pump feeds off.

Given these conditions, is it advised to regularly open/close the vents, seasonally or otherwise, for insulation or other reasons?

If you seal the crawl space the humidity can rot wood and cause corrosion of metals. I had a similar house in northern IL, I guess it may have had more humidity. When I bought it in the 70's I added vents because the joists were black in places. There was also corrosion in the galvanized electric boxes in the house. My crawl space "floor" was just soil.


How to remove this hinge to remove box cover I need to take the door off of this to get access to the bolts to remove it and access the inside:

According to the installation instructions (found here), there is a cover in the center that is removed, then two pins pull out, allowing the box cover to be removed.  Once removed, there are 4 bolts in the corners of the box holding the face plate on.


Adding house wrap behind existing board and batten siding I live in south-central Illinois, and the house is on top of a hill, so we get a lot of wind. The house is cold in the winter - partly because it is on slab and partly because it is pretty drafty. Most of the windows are in decent shape (Anderson dual pane) and don't leak much air. The house was built in 1965. Exterior is mostly board and batten wood siding (both boards and battens are a full 1" thick, boards are 12" wide). The house is quite drafty, and I'm considering 3 options. Labor cost is not a huge issue - I have two kids in their late teens.

1) Carefully remove siding boards, install housewrap, and reinstall the siding. May need to find longer nails, or add some construction adhesive to the nail holes to make the nails hold.

2) Remove the battens and use caulk or sealing foam to seal between the boards before reinstalling battens. This won't reduce air infiltration around the bottom of the siding.

3) Just use foam sealer around all the outlets and accept some draftiness.

Anyone have advice about options 1 and 2?

If you are going to do this you might as well go all the way.  The housewrap is kind of like saying you are cold so you put on some underwear.   Might warm you up a little but being fully clothed is what you want.

If you are taking the siding off you should be throwing up (at least) 1" XPS rigid sheets.   I prefer to put the housewrap up first and then the sheets.   You tape the joints on each.

After that the only three issues are getting the old siding up, making sure you have enough siding up, and extending the trim around the windows.

Remove siding.
Caulk and spray foam gaps, especially near windows.
Add housewrap and tape.   Note this will not take away all air movement.
Add 2" XPS (1" is fine).   With you and two teenagers this is a 4-5 hour job - it cuts with utility knife and really only windows take any time.   Get peg nails and tape.  In the corners you put up 2x4 plus 1/2" plywood.   Your house will be 4" longer.   Cut out right to windows and doors.
Add blocking plus trim around windows and doors to match new house depth (this is a different question and way easier than you think.
Add siding back on.   Like I said you will need an extra 4" per side.  That is why I asked if you have extra siding.

The housewrap is nominal.   There is no way in hell I am taking off all of my siding to just housewrap.   Adding insulation is a long-term investment in the house.   In heating and cooling in southern IL (I am near you) you will pay for the extra costs in probably a year.


Are there any consequences to not running air conditioner in a hot and humid climate? The AC in my house has been broken for several weeks, during which time the temperatures have gotten into the 90s with high humidity (heat indices over 100 the last few days). Because the AC is broken, the house is not cooled / dehumdified, and I wonder what the effects of that increased temperature / moisture would be on the house itself, personal comfort aside?

I'd like answers to include effects on furniture but to keep it on topic, let's limit it to how the framing, walls, flooring, and appliances would be affected.

There shouldn't be any permanent damage to anything structural, or furniture or appliances.  Those may absorb some humidity, but will return to normal when the AC is fixed.  But I would worry about a mold bloom.  I would consider running a dehumidifier (which, unfortunately would add heat), or getting a portable AC unit that you duct out a window.


Overflooding because the tons of rain? or is the WELL- PUMP broken? About two weeks ago, I noticed there is water slowly coming up from around the well-pump pit and puddling around the well-pump.

Here are some facts:

We've been having a lot of rain in the past month, 6 weeks.
The water table is kind of low in our area.
Our sump pump runs every 5 minutes - I timed it.
The well-pump is on the lower middle of a sloped backyard and when I step anywhere within 5 feet, even uphill from the well pump, the yard is wet.
The water pressure was fine until a couple days ago. Before; the shower can be running while using the any sink and there will be no difference in the water pressure. Now If any two faucets are in use, the pressure drops by half.

My thought is that with all this rain, the water table is so high that the water is flooding up around the lower end of the yard where the WELL is located. That will also explain why the sump pump is going off every 5 minutes.

My question is: Am I right in thinking the rain is causing the water table to overflow? or is there a problem with the well-pump?

I just don't want to call the well-pump company to charge me $100 just to tell everything is alright and just wait until the water table goes down.

Your well is likely fine just rising with the water table but you might want to check your pressure tank as suggested above. A change in water pressure suggests something is not quite right.


Can I glue a decorative tile to the existing tile for a shower niche? I just finished tiling a shower for the first time and made the mistake of not planning out the shower niche very well. I was left with some pretty big gaps where the different planes meet.  I am thinking about gluing a decorative tile around the perimeter of the niche, but am not sure if:

This is the best solution.
If the decorative tile will adhere to the glossy tile.

Any suggestions would be greatly appreciated!

1) No, definitely not the best solution. I think the best solution would be tearing out the tiles that surround the niche and re-doing it.

2) I am not familiar with wall tile, but with floor tile, you don't install new tile over old tile (typically) because of concerns of cracking if there's any movement in the subfloor. With your situation, I think the major concern is waterproofedness -- I'd be concerned around the edges of the niche whether there's any break in your cementboard/vapor barrier. Water might be able to get around the tiles that make up the 'walls' (in the Z-plane) of the niche, since grout by itself is not waterproof and may let water through.


Basement Subfloor at Bottom Stair Landing I am in the process of finishing my basement, but I ran into an issue with the new height of the floor and the bottom of the stairs. My new basement flooring is raised ~2" (OSB nailed on top 2x2s which are attached to the cement floor via tapcons).
I have yet to do directly in front of the stairs because I am fearing I will be breaking code. I have been searching around and have seen that there may not be more than a 3/8ths variance between stair heights, which my subfloor would obviously break, but was not clear if the landing is considered within this restriction.
If it does break code, do I need to modify my steps to accommodate the new floor height? I'm not terribly concerned with finishing the area directly in front of the stairs, but then that also leaves the issue of a gap between the cement and the new floor (tripping hazard?).
Any advice is appriciated.

New landing at height of last step

Build the new basement floor across the full room.
Add a new landing - really just another floor that is at the height of the existing bottom step. Depending on how you finish it, you may add a thin (max. 3/8" ideally, as already noted) layer on top of both the stair and the new floor to make it function and appear as one smooth surface. This landing should be at least 3 feet deep, though that includes the stair that becomes part of it.

That leaves you with one short step at the end of the landing down to the new basement floor.


Is a lip necessary on an HVAC ceiling register boot for use with flexible ducting? I've installed some new ceiling register boots to use with flexible ducting and realized after install that they have a smooth connection with no lip. I'm assuming they are made for metal ducting, as I think flexible requires a lip for a tight connection. How can I securely attach flexible ducting?

One idea I had was putting five or six screws around the connection to act as a lip. I also thought maybe there is a tool that I could make some dimples that would do the same thing. Is a lip even necessary for a solid connection?

Thoughts?

UPDATE: Since I don't really know the proper names for things, I think pictures might help.

Here is pretty close to what I have:

Here is the lip I'm talking about that is on the current register boxes:

Here is one with no lip:

On my current ducts, there are two zip-ties, one on the inner core and one on the outer insulation. The inner core zip tie is behind the "lip". I assumed this was necessary for a solid connection (Note: I'm using mastic, not tape. Whether one is better than the other is another topic). Here's a picture of the inner core I was referring to that I want to put the zip-tie on.

So I've now changed my question to: Is that lip needed and if so, any way to fake it if not there?

New answer thanks to updated question.

Yes, the lip around the rim of the opening I'd call it a "ridge" but I dunno if that's right) on the boot is there to help ensure a firm connection.  It's to keep the zip tie on the inner core from slipping free.  This is necessary (the keeping the duct snug, not nessarily the tie) if your ducting is going to be pulling away from the boot due to gravitational stresses - such as when the boot is above the duct and the duct can be pulled down, such as along a wall or below a ceiling or floor.  If your boot points down and the duct sits on a horizontal surface, you're good - no extra tension should happen.

Important note - neither mastic nor tape are intended to be structural - they don't serve to hold the ductwork in place, they serve to seal the ductwork so that there are no air leaks.

So the question really is - how do I properly secure my flexible ducting to the boot when there's no lip on the collar?  Answer:  Self-tapping screws.

Get yourself a box of those (the hardware aisle or the ductwork aisle).  When you go to mount your ducting, pull the outer insulation back up away from the core, pull the core over the collar, and use TWO screws on opposite sides of the duct (180 degrees from each other - noon and 6'o clock (or 1 and 7, 3 and 9, you get the idea) to ensure that neither side of the duct can pull free.

Use the inner to snug up the connection (don't over tighten!), seal with mastic (I'd recommend tape though cause of the insulation layer...), slide the insulation up as far as it will go and snug it up with the outer zip.


soffit to attic access on gable end? I want to install a camera/flood light under the soffit on the gable end of the house. Note the location of red arrow in below pic. After I take off the aluminum soffit cover, will I have access to the attic?

I'm thinking under the aluminum soffit will be hollow, then maybe plywood on the wall side that I would drill through to access attic?

I need to run a 14/2 wire to the location of the floodlight. The nearby soffit light wont' work, it's on a switch and I want the flood light to always have power.

Because you're on a gable end hit wall sheathing and sheathing on the gable end truss, depending on height. You'll want to try and drill through the sheathing as high as possible to get above the wall plates and truss bottom chord. You can drill through the truss if necessary.

Your best bet might be to route the cable around to the overhead door wall, where you'll find open bays between the trusses. There may be insulation baffles, but you'll have a relatively clear route.


Vinyl garage floor coating I was passing by a home, and noted that the garage flooring had a shiny vinyl coating, looking as if it were waterproof.

Does anyone know of this product used? And how long it lasts.

I used the same type of epoxy paint for a basement floor:

Rust-oleum EPOXYSHIELD Garage Floor Coating

There are a lot of different versions as well as professionally applied products. If you want to do it yourself:

Concrete, Basement & Garage Floor Paint at The Home Depot


14/3 to run a small 1650 watt Charbroil electric patio pedestal grill We have a patio outlet that is connected to an interior, 15amp outlet. I want to move the patio outlet about 15 linear feet away from its current location to use for a 1650 watt electric patio grill (a small Charbroil, sold in Walmart/Home Depot).

The circuit is wired with 14/2 cable.

We never use the interior outlet the patio outlet hangs off of so I'd like to just 'junction box' it and put a solid plate over the outlet (it's too close to some decorative dried plants anyhow).

So if I move the outlet and keep to 14/2, can I put the GFI and weatherproof outlet box on the patio and run the electric grill?

Most consumer appliances are made to plug into a standard 15A outlet.  Your wire (14/2) and breaker (15A) are both suited for this, and your grill uses (1650w / 120v = ) 13.75 Amps.  That all checks out.

GFCI outlets are required in exterior/wet locations, and a weather proof box is a good idea, so you have the right plan there as well.

I think the only other thing you didn't mention is how you are going to run the wire.  If it's outside, run it in the appropriate conduit and use the correct connectors (may depend on exactly how you need to run the wire), and you will be fine.


Code check: Installing a garage security flood light Below is my current understanding of end-to-end project for installing a garage security flood light. Wonder whether this is NEC 2017 code compliant or not. Any suggestions/recommendations are welcome!
Context:

An outlet is protected by 20 amp breaker
There is no attic access (another room above)

Outside:

Install 4 in. PVC Round Weatherproof Box with Five 3/4 in. Outlets
Glue 2 male adapters on 6" PVC and stick it through the wall
Use THHN to go from the round box to a junction box
Use 3/4 in. ACC Non-Metallic Strain Relief in central outlet [goes into a wall]
Use UF-B 12/2 cable to go through the wall

Questions:

How to screw something to the external wall like this (with and without a stud)?
Should I cover all 4 remaining outlets? Or should I leave the bottom one open?

Inside:

Use Wiremold 700 series to extend a ceiling outlet (protected by 20 amp breaker), use it as a conduit and a junction box
Use 12/2 THHN wires from the outlet to the junction box
Use UF-B 12/2 cable 12/2 THHN wires to go through the wall (in PVC pipe)

Questions:

I would like to have an ability to turn off this security flood light. Is it allowed to install a switch in unreachable location (> 9 feet)?

A surface mount box can be attached to the exterior siding (what is the siding?)
In some cases I like to cut the siding an inset the box and screw it to the sheeting
OR cut through the sheeting and make the box flush mount (old work box could be used in this case).
Since you have the UF a surface mount is fine I usually use 2 screw clamps, cheaper than a CGB and 2 screw clamps are listed for the UF. a CGB may or may not be listed for use with flat cable it depends on the seal some are hard plastic and those are not on the ones I have used and some are a soft neoprene and some of those are. But I would use the cheaper 2 screw clamp.
All the unused holes are required to be plugged if you are concerned with water accumulation it is acceptable to drill a drainage hole in the bottom of the box.
The maximum hole size is 1/4”.
As far as height NEC 404.8.A  all switches and circuit breakers used as switches limit the switch to 6’7”. There are switches that can be up high but these are a specific type not a common snap switch.


Vent to outside in gas hot water heater closet, can I seal it? In my laundry room I have a closet with a gas hot water heater and on the wall to the outside in this closet are two vents going outside.  This obviously presents a heat leak as you can feel the cold air coming into the laundry room.  I would like to close this up but I am not sure if that would present an issue due to the hot water heater being gas.  Is there a reason those vents are there and is there anything I can do about it?

Your gas water heater needs air to burn the gas. Without the vent, there's a possibility of air being sucked in through the flue instead, which could fill your house with carbon monoxide. So yes, you need the vent.

The exterior vent should have a flap/door on it that closes when there is no need for additional combustion air. If yours doesn't, then get it replaced with one that does.


Ground wire seems to pass through light switch I am trying to install a Kasa smart switch and ran into what looks like a ground wire that just passes through the switch(see image below). This switch is one of two that control a single bank of lights.

Is this in fact the ground wire?
What style of wiring is this?(do I need more information to be able to tell?)
Is this bad practice to pass a wire through this way?

Going to probably let an electrician sort this for me since I’m out of my depths, but want to know more.

That's a hot, not a ground
What you're seeing is an always-hot wire most likely, not a ground, that lands on the terminal screw then continues onward somewhere else in the circuit; some electricians will cut the wire and pigtail, others will use both terminals in a screw-and-clamp, and yet others will wrap a stripped section mid-wire around the screw as you see here.  The 3-way Kasas, fortunately, have terminal screws, so you can leave it "as is", or pigtail it; if you were using a switch with a wire pigtail built-in instead, you'd have to cut and strip so that you could nut the pigtail to the cut ends.
Good news: this is a conduit job
The yellow wires and the use of a metal box with a mudring also tell me that this is a conduit job, which is good news: it not only means that you likely have metal conduit providing your grounding path, it means that even if there's not a neutral already in this box, pulling a neutral to this box is an easy job for any electrician.  It also means that you don't need a grounding wire for the switch; instead, it simply can pick up ground via its mounting screws.
Good news #2: neutral appears to be present
The other good news is that since this is a conduit job, we know that white wires must be neutral in order to meet Code.  So, we know offhand that those two bundled white wires must be a neutral bundle.  However, since one conduit may have multiple circuits in it, we'll need to know more about the inside of the box in order to figure out if it's the correct neutral for you to connect to.
Bad news: this is a 3-way
The bad news about that pair of yellow wires connected to separate switch terminals, though, is that they tell us this is one end of a 3-way switch arrangement.  This means that you'll need the 3-way version of the Kasa smart switch, part number HS210, instead of a single pole switch, and will need to find the other 3-way in the complex so that you can replace it as well.


Correcting over-amped wiring... fire hazard? Trying to determine if I have a hazard I need to resolve...

I recently moved into a home where previous home owner did lots of dumb stuff.  One thing I found was that in order to get more stuff wired to a generator transfer switch with limited breaker spots, he disconnected one line from the breaker and then inside the home bridged the two runs so those previously separated runs would draw off the same breaker on the transfer switch.  Of course, his 15amp breaker there probably kept tripping as he had half the first floor now wired to it and so he dropped in a 20 amp breaker for that massive 14 gauge run.  Ug.

I noticed the problem and have put a 15 amp breaker back in place... but not until we had tripped the 20amp breaker at least once ourselves.  He surely had done the same many times before as he had 12amps worth of just incandescent canned lighting on there that I replaced with LED and still managed to trip with regular load on the other 20+ outlets on the combined run.

I also know exactly where he did the bridge and will be re-splitting the overloaded run.  While I believe I  have now achieved proper pairings to code (15amp breaker for 14 gauge runs), I’m wondering if I should be concerned about any damage caused to the lines during the period of over-ampped usage.

I did have one issue with a single can fixture that was on its own spur off that run that wasn’t consistently getting power on the supply line to the switch.  I disconnected that single supply line from the outlet it branches from and rewired that single light switch to a different nearby run (that outlet was working just fine even while there were supply issues to the switch so I feel I’ve isolated and mitigated that issue).  It seems unlikely to be related to the overloading issue given it would have only ever had 75-100 watts max load on it.  It seems more likely that any damage of overloading nature would be closer to the root of the branching run where the load would have actually been 20amps.  But I’ve not noticed any other supply issues and I can’t reasonable inspect the cables as it’s all behind finished wall.

My question - if I’m not experiencing any other issues, is there any more to be done?  What is the likelihood I have any sort of fire hazard in the walls from previous overloading?   Aside from very costly rewiring of that entire run, is there anything I can/should do to reduce risk of fire? Was wondering if using an arc-fault breaker would do anything? What do others suggest?

If there are any problems, they'll appear at the terminations first.

So as you work on that system, just keep an eye peeled for any thermal damage at terminations.  Discolored wire, melted insulation, arcing, anything like that.

Truth be told, 14AWG wire is allowed for 20A - just look at the table formerly known as NEC 310.16... but this presumes 75C terminations (e.g. the receptacle will not scald your child's finger if he touches the outside while a wire is cooking away at 75C on a screw) and a bunch of other favorable factors.  So there is a statutory rule elsewhere in NEC that clamps 14AWG ampacity at 15.


what is the cause whereby compressor working gets hot and stops, after cooled down picks up My challenge was that, I have this refrigerator I'm working on and after awhile it is working and then the condenser become hot as the compressor discharges excess heat, which as time goes on immediately stops working and has to be put off for awhile, just to cool down before putting back on. I thought may be it might be drier, which I did change, yet the excess heat persist. So what could be the cause for this.

Assuming the condenser coil is reasonably clean, possibly a weak run capacitor on the compressor.  If you have made changes to the refrigerant such as you would be required to when replacing the dryer then more likely contamination with a noncondensible like air or overcharge of refrigerant.

Edit:  I have assumed, perhaps incorrectly, that you are in the US.  Voltage too high or frequency too low for the compressor rating could also cause the compressor and condenser to get very hot.


What size Screw/Nail should I use for a 6 lb painting in drywall? I am sure you experts get tired of questions like these, but I'm a complete newbie when it comes to hanging things on drywall.

I ordered a piece of framed wall art, which is listed at 6 lbs. If I'm hanging this on drywall, do I use a nail, a screw, or a drywall anchor? It's on a small wall where I won't be able to find a stud.

This is a rental unit and I have no idea how thick the drywall is.

At 6 pounds, a simple picture hook will do.  Any box store or hardware store will have them and they will list their load rating on them.  Working from memory, I think the smallest size has a 10 pound rating.


What type of water pump is also a valve (e.g. will resist head pressure when off)? Many pumps, when turned off, will still pass water.  If there's any pressure at all upstream of the pump, the impeller will turn and water will leak through in the forward direction.

To prevent backflow of course, a check valve is used.

What's the term for a pump that forms a pressure seal when off, preventing flow in the pumped direction?

I believe the term you are looking for is a positive displacement pump.

However, such a pump is not generally constructed using an impeller and such a pump is only sometimes used for liquids.

Here is a link to a brief discussion of the characteristics of centrifugal pumps versus positive displacement pumps:

http://www.pumpschool.com/intro/pd%20vs%20centrif.pdf

For low pressure water applications a centrifugal pump and check valve in series are usually used to prevent back flow.


Can I insulate between a brick chimney and drywall? Can I insulate the space between a brick chimney and the drywall inside my home?

I am getting heat transfer from the brick to the drywall in the summer from the sun heating the brick. My thermostat is located on that wall and is causing the a/c to run constantly due to the false reading of the temperature of the wall. That wall is warm to the touch. Even setting the thermostat at 80°F the actual inside temperature is 74°F in the house. There is about a 2 inch gap in the attic between the chimney. I thought about pouring insulation in this space. I converted to gas logs which are hardly used due to the North Carolina climate. Even when used there is not much heating of the chimney. I considered moving the thermostat but would have to run the wiring down the outside of the wall and drill down through the floor to reach the furnace under the crawlspace. The chimney is inside the structure not on the side of the house.

If there is a straight open space accessible from above, you might consider  polyisocyanurate foam insulation. A 2 inch board has R-13 insulation.

You might want to consider a wireless thermostat.  There are numerous types (both proprietary and wifi) that would allow you to move the sensor elswhere even if the base station was on the heated wall.


Cook Top Temperature Too Hot I have a GE glass top drop in electric cook top (JP655) in my kitchen. Over the past week I have noticed that one of the burners is med-high to high regardless of what the knob is set at. Does anyone know of a potential cause or fix? I hope to not have to replace the whole unit.

The surface element controller has probably failed. Replace it. Personally I would use only a genuine GE part, but you may be able to get a genuine GE part cheaper than from GE. But if you already have a non-GE part on order you may as well try it. These parts cannot be easily tested with a meter by a DIYer. One just puts it in the range and sees if it works.

Note that your range will have different controllers for different sized burners, at least that is the case for mine.