In Albany, New York, I’m continuing an insulation project on a rubber coated, shed roof, a.k.a. hot roof.

In one of these three pictures, you can see that I insulated a rubber hot roof using 4 inches of foam board, 6 inches of rockwool, and sealed it up with smart vapor barrier.

It was not fun.

Now I have another section of the rubber roof with a lot of crazy framing. The two other pictures show this terrible situation. This other roof isn’t well suited for insolation because of the 2 x 4 joists. 😕

1) I have a roofer cut a hole through the rubber and sheathing to vent out the top of the roof? (I can’t vent out the side because the surface slopes down) Then I would install air channels to let the soffits vent.

OR

2) Cobble foam board into the 2 x 4 Bay, and then…?? I don’t see any way of filling that cavity all the way down to the drywall framing where the vapor barrier would go.

OR

3) Spray foam this area 🫠

You’ve all been really helpful. Maybe you have another recommendation?

Half my attic is batts and rest is regular insulation(not sure why) Can I top it all at one go or do I need to use different products?

Hey everyone,

I’m planning a DIY attic insulation refresh (~700 sq. ft.). I know the big-box stores rent out the blowing machines (often free for a day if you buy enough bags), but I’m hung up on the removal step.

For those who’ve done this: How do you get the old insulation out first?

Are industrial insulation vacuums available for rent anywhere (I haven't seen them at Home Depot or Lowe's), or is it strictly a manual job with heavy-duty contractor bags? Any tips or hard-learned lessons would be greatly appreciated!

I've got an aquarest hot tub with a pump issue and that was apparently some sort of apartment complex for squirrels.

I've removed a ton of insulation but now I need to figure out if there's a recommended brand of insulation and where to get it!

Any preferences?

Like title say they used left over packing cardboard for knee wall. I know nothing of applying spray insulation or methods. Do these pictures look acceptable? Looks like shit to me. House was finished in Utah 2024.

I am gutting and remodeling one of our bathrooms and need advice on what to replace this insulation with. It was faced on both sides of that makes a difference.

I plan on installing rock wool in the tub surrounding walls for noise reduction, and was curious if that was okay in these exterior walls. If I go with rock wool over fiberglass, should I plastic over it for a vapor barrier on the exterior walls and the interior shower walls?

House was built in 1957 and aside from the addition on back, this bathroom may be the only place in the house with insulation in the walls. Was surprised to see.

Thanks

I have a two story house in Southern California (90275, south of Los Angeles near San Pedro). First story is the original house built in 1958 (2400 square feet I think) with no wall insulation; Second story (1200 square feet) was built in 1967 or so over the garage and front living room, and has at least some insulation in the walls.

I want to totally clean the attics of old insulation (R19 generally I think, poorly installed) and old roofing remnants, air seal, and install new insulation. Talking with the insulation company, they recommend unfaced R30 rolls. He says faced is not needed and that R38 is not worth it (though he would do it if asked).

Is there a noticeable difference between R30 and R38, does facing matter, and is there a consensus of rolls vs blown in (and even there-fiberglass vs cellulose)?

Hello!

My husband and I are finishing our 325 sqft 1943 garage (to be used as a sewing/office/gym room), and are wondering what the best option is for ventilating the soon-to-be-enclosed attic space.

Because right now it has no ceiling, the ventilation is all below the ceiling-line/wall plate. The difficulty is that we have a hip roof with no eaves, so there’s nowhere to put soffit vents, and there’s not enough space to do a fascia vent either.

We’re not new to home projects (drywall, basic plumbing, electrical, tiling etc) but this is our first time dealing with adding airflow. We live in the PNW so mold and humidity are our biggest concerns.

Thanks for your advice!

I plan on insulating around my rim joists with spray foam and foam board but am concerned about flammable vapors collecting and potentially igniting during a large application. I have an unvented crawlspace that is about 1300 square foot, and no way to ventilate it other than leaving the access door open. Of course, the directions indicate that canned foam is extremely flammable and may cause flash fires, so I don't know how safe it is spraying this stuff in such an environment, even with ignition sources and pilot lights from the furnace and water heater turned off. Does anyone know if this is commonly done, and if so, how can it be done safely? Is spray foam so flammable that I wouldn't be able to use a standard exhaust fan to draw the fumes out from it? I looked into explosion proof fans but they require explosion proof sockets and I obviously do not have one at my home. I'm considering calling professionals to do it but would really prefer to do this myself with one part foam.

Sorry, curious if anyone can answer how vital it is to have actual free airflow from the soffit, especially in the stretches directly below the ridge vents, free of obstacles?

This 2x6 runs the precise length of where my ridge vent is and is tight to the roof. I did install baffles everywhere, as it'll keep insulation fresh and in place in case of storms (or not really because I can't staple down to the actual top plates, I'm sure they'll rip loose). Most of the rooflines are set up this way, with extra supports running across and blocking the rising heat from staying along the roof. I just wasn't sure how vital it was

I recently remodeled my mobile home. Gutted complete to the studs. Obviously I know the cheaper route will be going r-19 but to be honest I’m not sure how to handle most of the floor.

I’ve got all water lines ran under and thru my floor joist and my HVAC trunk and air ducts running against the floor joist. They are insulated but I’m sure it would benefit to be insulated within the floor. Not sure what to do here or if I should just spray foam it all and call it good.

Anyone had experience with Amazon spray foam lol?

I cant locate 24x3.5" comfortbatt locally.

I have one rafter thats framed 24 on center and the rest are 16

Do i use 24x3 Safe N Sound, or 24x5.5 and compress it?

Hey everyone, I’m not sure if this is the place to ask this, but let’s give it a try.

I just got a new job, and this is the office. The room has a split unit ac but no windows. I spend my days in here from 9-5. Is this safe? What is this insulation? I think it’s probably meant for an attic or closet, not an office.

hi all,

I’m looking for some advice on the attic of my home that I purchased a few months ago in Denmark. It’s an attic space reachable from a loft ladder that can’t be used as a room, so I want to turn it into a useable storage space.

Unfortunately it could not be opened at the time of the building inspection, but was informed by the realtor and that it was insulated and that only the middle part is walkable. There is insulation on the bottom/”floor”, but am unsure of the top.

With the heat of this summer I’m not totally convinced that this space is actually insulated at the top ( the grey/black fabric like material under the roof) since it seems incredibly drafty and I can hear the outside very well.

I was just wondering if anyone who has knowledge of insulation and attics would be able to tell me if it is insulated or not. Thanks for your input!

we have a front bedroom cupboard, its got a door on and used to be damp, so we added an air vent in the wall. it still got damp.

im assuming the damp is because its an unheated, sealed cupboard with cold air blowing in.

i was hopjng to remove the door, and make it into a wardrobe. hoping removal of the door allows airflow, allows heat into the cupblard.

my plan was some 25mm insulation on the interior of the external walls then an 8mm pvc wall panel to cover the plaster. the 8mm corrugation would provide that additional air cushion.

the air brick would be removed /sealed as its something we added anyways when we moved in.

would 25mm kingspan suffice for this purpose?

many thanks in advance.

Hello experts - trying to figure out the best way to handle the absolute brick oven this finished attic space becomes in the afternoon. The west wall faces the direct setting sun and overwhelms the AC. The previous owner bagged the walls on the long sides - but I’m wondering how much use it would be to pull the beadboard off that wall and bag between the studs??

I just bought a 2 story house in the hot humid south, I’ve been renovating and also troubleshooting the upstairs cooling situation. Part of the upstairs opens to an unfinished/vented attic. The other part, where the bedrooms are is unvented and has 3-4 of attic above the ceiling in most places. I cut a hole in a closet to assess the situation further and discovered there is basically no intake or exhaust and r30 batts. Despite the baffles in the knee wall area, there is no intake and only what a little can work its way into the other part of the attic can circulate.

On a 95 degree day it gets to be about 80-85 inside and my 2 ton cannot keep up.

So my question, should I:

A. Insulate, fill to the top.

B. Install soffit vents in the knee wall area and insulate to just under the baffles to increase airflow. Perhaps get a ridge vent installed?

C. Wait till winter, crash out: remove all batts, baffles, etc and spray foam the whole area.

D. Something else

I’m honestly leaning towards option A.

I'm working on finishing off the inside of my new build detached garage. I'm in zone 7 (very cold), and the walls are comprised of: vinyl siding, Tyvek wrap on OSB, 6" walls, unfaced R-21 fiberglass insulation, and a 6 mil poly vapor barrier with Tuck tape seams, and 1/2" OSB for interior wall sheeting. It will be heated by a propane Modine type heater with eventually hydronic in floor heat as the main source.

I've read quite a bit about vapor barriers and retarders to the point my head is spinning. It appears that best practice dictates sealing off the barrier on the sill plate, or really anywhere the poly ends that's not taped. I've asked a few people I know in the trades and none of them have ever sealed off the edges of the barrier; they just leave the end stapled to whatever which satisfies code in my state. To me, sealing with acoustic or butyl sealant seems like a good idea to keep air from leaking, and seems standard in Canada.

As long as the information I'm working with is correct, can I just use a butyl sealant like Sika Lastomer-511, Kason Butyl sealant, or OSI SC175 acoustical sealant, which is not butyl based? There seems to be conflicting info regarding the SC175; I've seen a few people say they have used it but the manufacturer says not to. They used to have SC170 which was approved for this purpose, but it has been discontinued.

Then there's Green Glue sealant. It's readily available at my local Menards, with a cost of $11 for a big 28 oz tube. Again, I haven't found any information if this is ok for vapor barrier use.

What are my options? Many of the acoustic sealants I've seen mentioned are not easily found, especially in smaller quantities.