Insulate when doing repairs

mountainmoma's picture

It is always a good time to up insulation. My house has a utility room, same slab as garage, it is a pass thru between garage and kitchen. When the house was built, they thought they should insulate the wall between the utility room and the garage, with no insulation between the cold, large utility room and the kitchen and downstairs bathroom.

A couple years ago, I replaced the, broken plastic shower in that bathroom, and then it turned out I had to replace all the house plumbing. That means the walls were open. More walls, due to the plumbing issue.

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mountainmoma's picture

the cabinet won, I have the only bathroom remodel in this demographic that kept its 1974 built in base cabinet, which is more ecological.

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mountainmoma's picture

got to bash in the drywall though, to allow plumbing access and insulation, above the cabinet

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mountainmoma's picture

so the wall was insulated and plumbing replaced without moving the cabinet. Foamed in Polyisocyan.... acting also as a vapor barrier, then some recycled cotton denim insulation batts to fill the rest of the space. The cotton batts in this location were from a neighbor who was getting those weekly meal cooking boxes, the cotton was the insulation from that, wrapped in plastic. I took it out of the plastic. Making use of leftover polyisocyan.... pieces as it was not for a radient barrier in this location, just insulation and vapor barrier. This is above the vanity cabinet, so much plumbing, the other bathroom is right over this, and the water heater is in the utility room right behind this.

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mountainmoma's picture

under vanity cabinet

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mountainmoma's picture

then the recycled cotton insulating batts on top

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mountainmoma's picture

This project is on hold due to the fire remediation, but it has all drywall work, plumbing, insulation, tiled shower and tiled floor. -- just needs the bare drywall to have tape/mud and maybe plaster or paint someday

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mountainmoma's picture

The tiling in the very small shower stall, replacing the worn out fiberglass stall was what led to finding pumbing issue, etc....I made it curb less in case I injure myself again, or get old. It is small, the exact footprint it was before. The tile is recycled glass, made 50 miles from here from local scrap glass, this was from the boneyard of the manufacturer, they no longer make this.

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mountainmoma's picture

This tile was at a senior citizen run used store, It is pinker than the quarry red tile in the great room hallway, but I thought it blended well, and the price was .50/sq ft. Natural stone of some type. This photo looks nice, as it was directly after being sealed and before being walked on ! it usually looks much lighter due to dirt blowing in the windows at night and settling on it.

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mountainmoma's picture

So my utility room ( which mostly functions as a large pantry and laundry room) had smoke damage during the fire. It had the ceiling and insulation taken out. So then might as well check if anything else needs to be done. Decided to move the laundry area, to the old darkroom area ( the utility room area of the water heater, behind the bathroom) and away from food storage, the way they kluged in a washing machine drain where it was meant that it was open behind the kitchen cabinet, no drywall, to have the drain pipe go into the kitchen and down the floor there. Realy. about 4 square feet of no wall, this is like an open window all the time for energy loss. Then, why not a light switch by the other door ? And ... The electricians noticed a problem. More wall areas get cut open. If that small, uninsulated wall area is going to need 3 large patches, so almost half the area patched, and the ceiling is all gone, well, just take that off and the bonus is now that area can now be insulated too.

They do not make the recycled denim insulation, it stopped during COVID, but I found and ad of someone selling a bale of it. That is the door from the utility room to the kitchen, it has already been replaced with an insulated door a few years ago.

Air sealing is VERY important. just hiding issues behind drywall causes heat loss, some of this was hid before. If you can see that area in the open left wall cavity, top of it, orange great stuff pro is blown in ? That area was open to the kitchen across the whole wall. The kitchen has a dropped ceiling. That is the area above the dropped ceiling. Air gaps like that are more important to fix than insulation. The 2 patches between the upstairs floor joists, rectangle on left, orange circle. Those were cut last month by the electricians to do the wiring rerouting, and open also to that area above the dropped kitchen ceiling.

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mountainmoma's picture

Huge wire run area. Showing the orange foam for the part left open during building, and then the circles cut into the blocking by the electricians. That is a brand new main circuit panel, get things fixed now while we can get supplies.

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mountainmoma's picture

I shoved insulation pieces into the area between the cut opening and the new panel. I used a small piece of WOOD -- wood doesnt conduct electricity, even though it shouldnt have mattered -- be safe. Then I had thinner pieces of insulation, in my case, I still had a little of the packing material insulation, which is thinner, otherwise you need to tear your thicker insulation down the center --- wear eye protection, sleeves, and a respirator if using fiberglass.

You cant just cover the top of a mess of wires or pipes with insulation, leaving air spaces. The point of cavity insulation is to impede air circulation within the cavity. It works if it FILLS the cavity. That means you have to rip it apart and have some behind the wire, in between the wires, on top of the wires. This cavity insulation is impeding convection, one of the only 3 types of heat transfer. It is also fluffy, so it does not conduct well, thus also impeding conduction ( all that wood you see does conduct some heat, not as well as metal, but better than fluffy insulation).

The area below the panel still needs me to rip apart and shove insulation into it. It would be nice to have some blow in insulation, but no one in the free exchanges seems to have any, but someone did give me alittle more of the cotton batts, as that is nicer to rip apart than fiberglass.

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mountainmoma's picture

Notice that the wire penetrations have been foamed. Those wires enter the bathroom, heated area of the house, on the other side of that 2x4. All penetrations between heated and unheated areas must be foamed and sealed. If not foamed, then use an old school plumbing caulk. But, something.

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mountainmoma's picture

The area in the photo is from by the water heater and opens into the wall in the upstairs bathroom under the vanity up there. I had no idea. They just decided to leave off blocking in a few places there when building. I foamed the plumbing penetrations thru the 2x4 on the bottom, I will cover this side with drywall or plywood, then insulate the wall cavity from the other side, as it turns out that the upstairs bathroom also does not have any insulation in its exterior wall ! But, that is for another day. Caulk and seal all cracks and openings !

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mountainmoma's picture

that is what started this area. The ceiling. The ceiling is unvented, so it is not supposed to have batt insulation under building code. I think maybe a dense batt insulation like rock wool, cotton or wool might be ok, but I dont know and I do know it would not be to code. There was a mold problem previously, years ago, in that ceiling as it did have the fiberglass batts and also had both the stove fan and downstairs bathroom fan just vented directly into the utility room ( which itself has no windows or venting ! the bathroom fan now is routed to the outside, the stove fan no longer vents anywhere) . Spray foam is legal, but in an inclosed retrofit area that could cause problems as it has no way to outgas and I have asthma. I actually want this area to be cold, but I don't like it getting too hot as I store food there. So, I almost put in just a radient barrier, but I had some sheets of polyisocyan.... free, leftovers from someone elses remodel work, and that also will impede conduction and some convection there too. If that foam panel is up against the underside of the roof deck, it is legal and should keep moisture from condensing.

There must be an air gap for a radient barrier to work, so here you see the shiny side down, and there is an airgap between it and the drywall. I did not fill this with batt insulation.

While I was installing, I could notice the difference in heat coming thru the cavities between the joists where I had placed this and the blank one next to it. I used an infrared thermometer and there was a 50' F temperature difference between the area with no radient barrier and the place where I had just put it.

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ClareBroommaker's picture

!!! impressed !!!

mountainmoma's picture

I found out how much nicer it is to work with the great stuff pro gun than the cans. Wish I had known about that years ago. Less mess, none in my hair with it, better control and precision, faster.

Sealing the edges does 2 things, it helps hold it up, and it keeps air from getting to the underside of the roof deck where it could condense. We held the pieces up with a couple nails under, sideways into the joists, to hold it tight until foamed.

I also insulated the blocking, in between the joists. But I dont have a photo of that and now the drywall is up.

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lathechuck's picture

I have read (but don't have a source) that home wiring should not be embedded in thermal insulation, because the wiring is rated for electrical load based on heat (due to load current) being dissipated by convection of surrounding air. The rating for wires enclosed in a raceway, for example, is less (lower current) than for exposed wiring. Especially now, with high-efficiency LED lighting, there may be many circuits in our homes that draw only a small fraction of the fused current (e.g. 10-20A), but running an electric space heater could be a problem (e.g., starting a fire inside the wall).

mountainmoma's picture

As, for example, all wires run in attics are literally buried under a few feet of loose or batt thermal insulation. And, any wires in external walls also of course are covered by insulation ? I mean, yes, I can see that wires wont dissapate heat as well if they are covered, but arent they covered usually ? We need an electrician to chime in.

lathechuck's picture

From: https://www.oldhouseweb.com/how-to-advice/insulation-precautions.shtml

"Also, if your home is very old, you may want to have an electrician check to see if the electrical insulation on your wiring is degraded or if the wires are overloaded. In either of these two situations, it may be hazardous to add thermal insulation within a closed cavity around the wires because that could cause the wires to overheat.
If your home was wired using a now obsolete method called knob and tube wiring, the National Electric Code forbids the installation of loose, rolled, or foam-in-place insulation if the insulation would surround the wires and prevent heat dissipation from the electrical conductors to a free air space. This is for fire safety!"

On the other hand:
https://atkinsoninspection.com/can-you-lay-insulation-over-electrical-wi... says:
"Can you lay insulation over electrical wires in the attic? Yes, you absolutely can. You can lay insulation around the junction boxes as well. Making sure that the insulation is of a fiberglass material will not only ensure a fireproof setup but also reduce airflow from the home through the attic.

Understanding what type of insulation to use in your attic is key as to whether or not it can cover electrical wiring. Insulation made of fiberglass is nonflammable and is a great option when it comes to covering electrical wires in the attic.

However, the more popular insulation choice in homes these days is cellulose fiber. Unfortunately, cellulose is made of recycled paper and can be flammable in the right extreme heat temperatures."

David Trammel's picture

My personal opinion is that too many people overload their individual electrical circuits with additional outlets. Its easy to think, what's the problem if I just add one more outlet? Electrical wire is rated for a certain amount of amps, and while it has a extra for safety, its easy to get it over the typical standard of 10 outlets for 15 amp and 13 for 20 amp. When you do, it heats the wire and can cause a problem.

This doesn't speak specifically to laying insulation over wiring but this video has me rethinking my plan for my attic. The attic is typically where you have the most contact between wiring and insulation.

Building a BETTER attic - Unvented + Conditioned attics 101

I've said before that extreme heat is my number one concern and my focus of my upgrades to the house. I had planned on just adding another deep layer of insulation on top of what is there, but now I'm thinking I may clean all the loose insulation out, and insulate the roof joists instead.

I have been doing the electrical for my basement build and plan on upgrading the existing wiring and electrical panel. That is one way to mitigate the risk of fire, add new circuit breakers and new electrical circuits, instead of adding outlets to existing ones.

Good thing, the new "Inflation Reduction Act" actually gives a rebate for replacing and upgrading the panel, along with many other home improvements. Here's a link to an article about the Act and its rebates.
Biden's inflation law offers up to $14,000 for home upgrades. Here's how to qualify.

I'm two weeks from moving into the new place and should be bringing the new website online then. I expect a ton of activity here this Winter.

mountainmoma's picture

You can insulate the ceiling and take out your other insulation.

But, if it were me, I wouldnt throw away the existing insulation I would leave it there and just add a radiant barrier up between the rafters. It can be insulation plus radiant barrier, or just a radiant barrier. But why take out and throw away the existing insulation ? YOu can staple up a perforated radiant barrier to the roof joists, like this ( I am not endorsing tis particular one, there are a few sources for this, shop around) http://www.energyefficientsolutions.com/ARMAFOIL.asp

David Trammel's picture

I think the reason they removed the old insulation was that they planned on using it for storage. If you do that, now you are required to put a fire-resistant barrier between the attic and the lower part of the house. Typically that is with fire-resistant drywall nailed to the floor joists. If the old insulation is higher than the floor joists, if there are added layers or volume, then you'd need to remove it to get to the joist.

There might be other issues, I'd have to look over the video again. Since I can't use the attic for too much storage, because the access is restrictive, I will probably add an additional layer of rolled-out batting AND insulate the roof joists as well.

I have a bad feeling that the extreme temperatures of climate change, in the form of 100+ degree days-long heat events are going to happen quicker than I anticipated. Maybe we crossed a tipping point. It just seems like we're seeing a rash of those these last few years. That means a priority of insulating and conserving.

mountainmoma's picture

I asked him his thoughts. He says it would have to be old wire to be an issue. Knob and tube for sure cannot be buried, and maybe houses that are right after knob and tube but still super old.

My house is only 50 years old, the materials are fairly modern, the amount on each circuit not excessive

And, as far as adding an outlet or two in a line. Depends on house. But, realy, we have outlets scattered around for convenience, like being able to plug in a vacume in various areas, but we are not using a vacume in all areas at once. And, even if somehow too much is plugged in, the circuit breaker and wire should be set compatible, so your circuit breaker will trip before you overload the wire.

If you have reason to think that over the years, your circuits are not correct, this should be remedied by your electrician ! For example, you notice turning on the microwave when the refrigerator is cycling trips your breaker, etc... then yes, dont do any othe rupgrades until your electric is sorted out, including insulation.

David Trammel's picture

I agree with you MM, if someone has underlying issues with your home's electrical, like having knob and tube, then you need to address that before too many additions or modifications. Lucky knob and tube is very rare. Mostly I've seen the old two single wire electrical circuits. I have that.

As I am doing my upgrade, I'm running parallel circuits using 12 gauge 2 wire (2 conductors, 1 ground) wiring in the walls and ceiling, then once it's done, unhooking the old wire and hooking the new. Eventually, I'd like to replace all of the old wire and also upgrade the old breaker box from the 100 amp it is now to a 150 amp main.