Insulation is any material used to slow the transmission of heat or reduce the transmission of sound. Typical materials include fiberglass, foam, blown cellulose, and reflective foil. This should not be confused with weather stripping.

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How can I insulate a basement wall that has 1x1 framing installed on it?

It is freezing in my basement so I decided to re-insulate my daughter's bedroom. I removed the old paneling walls to find that it wasn't insulated! There was a water barrier and a heat shield. My ...
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How do I retrofit a junction box in an insulated wall?

Typical cold climate construction: Drywall, 6mil vapour barrier, fiberglass batt insulation. How do I retrofit a junction box and maintain the vapour seal? To be clear, by 'retrofit', I mean the ...
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576 views

How to properly seal the transition between basement wall framing and spray-foamed box joists?

We're looking at insulating the box joists of our concrete foundation. We have 2x3" walls framed which are holding batt insulation, which are 3-4" away from the wall (to accommodate a layer of batt ...
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1answer
616 views

Venting the attic space during summer to cool the house

The air in my attic gets superheated during summer, from the sun baking the (clay? terracotta?) roof tiles (I live in Sydney, Australia). I have good ceiling insulation, and even put in some sarking ...
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How do I design a 100 mm thick barrier that maximizes thermal and acoustic insulation?

I need to design a thermal and sound barrier - walls of a cuboid-shaped space. Imagine it is a free-standing bike shed in the fields. The walls can not be thicker then about 100 mm (4 inches). The ...
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Do I need an air space between insulation and flooring in the attic?

As part of a local council grant, I am getting my attic floor insulation (2 inch thick fibreglass) replaced with 4 inch thick insulation. It will lie between the joists, on top of the plasterboard ...
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724 views

Adding insulation to basement that already has vapor barrier

I have leftover insulation from doing my basement, little bits and pieces. In between the joists on my basement ceiling it is insulated with vapour barrier already from when the house was built. ...
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2answers
783 views

When insulating with closed-cell Spray Foam, what ERV and HVAC resizing considerations should I bear in mind?

I am building a 2800 sqft, two-story brick home in Austin, TX. I have heard many good things about the benefits of insulating with closed-cell Spray Polyurethane Foam (ccSPF)1, and have requested ...
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Can I install cellulose insulation without a blower machine?

I've purchased a few bags of loose fill cellulose insulation from the local hardware store (GreenFiber brand). How will the insulation work if I don't put it through the machine to fluff it and force ...
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Do I need to “protect” low voltage cables that are run through an insulated wall?

I'm planning to run speaker cables from a new outlet at an uninsulated wall to a new outlet at an insulated wall. I've already run Cat5e and coaxial cable to the uninsulated wall, and am comfortable ...
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What material should I use to insulate floor over a bumpout?

My dining room has part of it bumped out about 2 feet overhanging from the foundation. The floor over this overhanging part gets cold in winter and I'm thinking about insulating below it. I've done ...
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What is the proper way to insulate box sill joists in the basement?

The floor joists of the first floor are sitting directly in breaks in the concrete/cinderblock walls, and there's large gaps all around the edges. I've done some looking around and it appears that ...
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1answer
394 views

How to cover gap below garage back door

I have a 3/4" gap between my garage back door (see image. blueish color is outside evening light). Looking for a good way to cover this gap with two goals in mind: Stop rodents from coming in Help ...
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1answer
252 views

Can I spray foam up to roof sheathing when air sealing skylight tunnel?

I've been doing some air sealing in the attic with canned spray foam and I'm about to tackle my skylight tunnels. They are framed and covered with drywall. I have easy access to them in the attic and ...
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3answers
549 views

Should I install external basement insulation that does not extend above ground?

Question : Is there a way to calculate energy savings for external, 2inch insulation on basement walls that does not extend above the soil surface, leaving the top couple feet of foundation wall ...
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453 views

How to plan for the future when installing a new roof?

We're hiring a contractor to take off the existing roof, repair/replace any rotted sheathing and rafters, and install a new roof. We've also asked that they add a new plumbing vent stack for a new ...
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326 views

Insulation in the attic

I have moisture and a moldy smell in my attic. I had someone come out and open up the eaves and soffets more. It did seem to help but I still have some smell and some moisture. I have insulation on ...
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611 views

How do I fix incorrect attic insulation?

I have loose fill attic insulation. It seems to have been moved around and become compact. Is it just as easy as getting in there with a broom and 'fluffing' it up and moving it around, or do I need ...
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How can I add insulation to my roof?

I have an old 1930's house, the upstairs of which is in the pitched roof space. I've just checked and it has no insulation what-so-ever up there, so it is very much the same temperature as a loft at ...
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441 views

Can I add rolls of unfaced insulation to increase the R value of my attic insulation?

I live in a two story home that is approximately 150 years old. The attic floor is constructed with large beams and old wood planks laid across the complete surface area, rendering the attic useful ...
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2answers
363 views

What should I do with insulation in basement ceiling?

I am fixing up my basement, and to make it seem bigger- we decided to remove the drop ceiling and are going to have the exposed ceiling and duct work sprayed black. There is some insulation around ...
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2answers
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What are the differences between hot and cold roof systems?

Can someone explain the differences, pros and cons of a hot roof vs a cold roof? I would like to vault a ceiling in an addition off of our family room, taking the drywall all the way up to the roof ...
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Can I put rigid foam on studs to prevent thermal bridging?

I'm re-insulating an interior wall & putting up drywall to replace the old plaster walls. Rather than screwing the drywall directly into the studs, I'm toying with the idea of putting a 1/2 inch ...
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1answer
454 views

What is good advice for a beginner layng insulation?

Background I have a manufactured home from the 70's with metal siding, wood studded walls and fiberglass insulation on the inside. I had a clogged gutter, which caused water to run behind the siding, ...
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258 views

Glue crawl space rigid insulation

I've dug a trench around the perimeter of my crawl space. Then I planned the next steps. I took a week off but I'd like to finish this project next weekend. I am going to glue 2" R-10 FOAMULAR 250 ...
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456 views

How can I replace ceiling gypsum board and loose fill insulation at the same time?

I lost most of a ceiling panel due to water saturation and collapse. It was removed along with insulation residue and a temporary fiber board panel tacked in in its place. Now I would like to install ...
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How do I know my current R-Value for my attic?

I am a first-time homeowner. One thing that was noted on the house inspection was that we needed more insulation for our attic. In my area, the recommended R-Value is 38 according to the ornl.gov ...
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170 views

What to do with this exterior insulation?

We have these sheets of pink insulation with a light coat of concrete-paint-like stuff (?) wrapped all the way around the base of the house, and as can be seen, it is degrading in both appearance and ...
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Installing bathroom exhaust fan: what to do with vapour barrier and insulation?

I'm adding a bathroom exhaust fan, which is being mounted in the ceiling of the bathroom (in the attic) and venting out through a vent in the wall. right now, there is a vapour barrier (paper) ...
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884 views

Should I insulate my roof on the inside or outside?

I am renovating my house and am completely redoing my flat roof: ceilings, insulation and roof covering (I am planning to use EPDM rubber). In case it is relevant, I am living in the Netherlands. My ...
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1answer
139 views

Is a sealed attic appropriate for Southern California?

I have a two-story house. Half the house has a cathedral ceiling (which will be left as is) and the other half has a traditional attic with no soffits. The only ventilation in the attic comes from two ...
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587 views

Air sealing a whole house fan

I have a whole house fan installed in my house from the previous owners. I love the fan, as it lets me cool down the house quickly in the evening -- or after I fill the house with smoke from ...
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How effective are outdoor foam faucet covers to prevent freezing?

Everyone seems to suggest using those styrofoam faucet covers to help prevent the pipes associated with the fixture from freezing. They're cheap so I have them anyway (plus I'm not in a hard ...
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Should I use foam spray insulation in my crawl space?

My crawl space has no insulation. The dirt is wet near one of the walls. There have been termites in the past. I'm thinking of insulating the ceiling (between the joists) and the walls with foam ...
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2answers
682 views

Why is the upstairs a lot hotter in a 2 story duplex?

I've lived in my current duplex for about 5 years now and every summer, my upstairs portion of the duplex gets noticeably hotter than downstairs. I couldn't give an exact measurement but 10 degrees ...
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Should I insulate air conditioner coolant pipes?

I recently replaced some rotted insulation on the coolant pipe that runs out of my AC unit and into the evaporator in my house. When cleaning inside the actual AC unit itself I noticed that the ...
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Can my drywall act as an air barrier?

I am preparing to improve a building in a cold climate zone. Since it does not seem to be properly insulated, I am reading a book about insulating and weatherizing. That teaches me that I should ...
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How should I insulate the walls and ceilings of this 1920's semi-detached brick house?

I'm renovating a 1920's semi-detached house. The plaster on the walls was slapped straight on the wall about an inch thick, and the ceilings were lath and plaster which had been overboarded. Most of ...
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Should I add insulation to basement ceiling?

Currently doing a reno on our basement. After roughing everything out, I have insulated the outside walls with R13 (2x4). The house has never had insulation in the basement. Should I insulate the ...
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how to achieve a reduction of noise of -60 dB in as little thickness as possible of insulation material?

I am looking into materials to acoustically insulate a room, and I need to do it in as little thickness of the material as possible. I found something called Balterio which is a 3 mm thick stuff sold ...
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What happens when a vapor barrier is too close to the cold side?

The vapour barrier must be installed on the warm side of the wall, that is on this interior side of the house. It is permissible to have it sandwiched in the middle between two layers of insulation, ...
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3answers
108 views

Will foam-filling this gap create problems?

I'm trying to find out if I can spray-foam fill a gap in my ceiling. I have an almost-flat rubber roof, 1" foam, wood planks, then a gap created by 2x6s, then the sheetrock ceiling. I'm in PA, climate ...
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2answers
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What is used to seal around glass in fireplace doors?

The glass in my fireplace doors have felt-like strips layered in between the glass and the metal framing of the doors. I recently had to have a piece of glass replaced and they lost the strips. Now ...
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3answers
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Should I use Tyvek or tar paper on basement walls?

We are going to be redoing our basement which was done in the 60's and very cold. We have been told to apply Tyvek or tar paper to the walls, stud, then vapour barrier and drywall. We plan on using ...
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2answers
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Are there any dangers associated with rigid foam insulation?

Is there any danger of bad fumes/gasses being released from polyisocyanurate or polystyrene rigid foam insulation? I'm planning on insulating my bedroom from the inside (ie: putting the insulation ...
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498 views

How do I insulate space in loft to create music studio

I have 3 DIY created rooms in my large live/work studio/artist loft. They are made with 2x4 and 2x6, framing with drywall walls and plywood ceiling. The apt has 14' 7" ceilings so we just have ...
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Can I cover junction boxes in the attic with insulation?

This may be a duplicate of What are the codes for electrical wiring in attics? I have an attic which is accessible via a ladder through an access panel in the garage and in a bedroom. The trusses ...
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Is there a significant benefit to using plastic window insulation year round?

In order to help save more money and funnel more of those savings to debts, I'm looking for more ways to save money. I've heard that puting plastic window insulation over single-pane windows ...
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2answers
230 views

How can I insulate a stud bay containing a subpanel?

I'm putting a subpanel in the outside wall of my attached garage, which I'm also insulating so I can work out there in the winter. I'm wondering what steps are worthwhile to air seal and insulate ...
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How do I fix air leak in windows?

Our windows in the back of our house receive a lot of wind. When it's windy or very cold, the air is coming in through various crevices: window track and space between window. The windows are about ...