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3 Answers

How do deviations in average winter temperature affect energy consumption?

Off the top of my head I would expect a five percent colder winter to cost five percent more for heating, all things being equal.

Asked By norm farwell | Oct 24 14
12 Answers

Flat roof insulation

I have built an extension to my house with flat roof, continuation of the existing house. The rafters are 16 in apart and there is 6 in left for the insulation under the sheeting. The plans are requiring R30 insulation and the building inspector requested hard foam Thermasheath- 3, 5 in thick, leaving 1 in for breathing. The drywall was not installed yet, when water from condensation came down all over the place. There are vents on both sides of the roof, in each bay under the insulation level, not allowing the hot air to escape.

Asked By Angela M | Nov 22 13
6 Answers

Add R-14 Roxul between the garage attic and the house?

I am currently in the process of insulating my attached garage using Roxul R14 "ComfortBatts". I live in Winnipeg and from experience -- when I did this in my last house -- it can improve the temperature by 10-15 degrees Celsius in the winter, without any heating. (And that was with a non-insulated garage door; my new house has insulated garage doors!)

Asked By Mike Lucas | Oct 23 14
7 Answers

Using foam sheeting & faced fiberglass batts

I am insulating my garage ceiling and have laid 1" foam sheeting above the horizontal 2x4 of the trussses. My plan is to put faced fiberglass batts between the trusses up to the 1" foam sheets. Then I would like to put another 1/2" foam sheet over the fiberglass batts, sandwiching the faced fiberglass between the foam sheets. Is there anything wrong with doing this? Thank you for your help!

Asked By Mark Woyak | Oct 23 14
2 Answers

Good idea to insulate old house with cellulose?

I have a house that is well over a century old, its balloon framed and has no insulation in the walls, i am planning on getting dense packed cellulose, but i want to know if i am creating any moisture problems or other issues that should give me pause.

Its vinyl siding over original wood siding on wood planks with 2x4 framing and plaster and lath inside.

Asked By Alan B | Oct 23 14
5 Answers

Insulation in old home repair

Hello, I own a 1931 home. I had a window leak it damaged the plaster on an interior wall, roughly a 2'x5' section. Behind the plaster and lath was a later of loose insulation and behind that bound newspaper. Much of the newspaper was rotted, as was a section of the wood behind it. The wood backed the exterior stucco. I removed the newspaper and wood. I am unable to replace the wood that backed the stucco.Instead and added 1" rigid foam.

Here's my question: What do I use next to insulate before I put on the sheetrock, faced or unfaced fiberglass...or something else? I live in Minneapolis.

Asked By Tom Ives | Oct 21 14
4 Answers

Spray foam over XPS on external wall

I purchased about 600 bdf of spray foam, and had planned on using it for my rim joists of my baasement (about 200 board foot of it). My house is a walk-out, so I have a combination of poured concrete walls and above-grade 2x6 stud-framed wall in the basement level.

I have sheets of 1" XPS available, so I was thinking about layering the XPS rigid foam sheets on my 2x6 walls, at 2" thick (possibly 3") and then covering that with a 1" layer of spray foam to air-seal it.

Asked By Jeff M | Oct 22 14
2 Answers

Insulation of the interior stem wall

I am building a 40x60 metal workshop. It is slab-on-grade and I had specified 2" rigid foam on the interior of the stub wall, thus creating a thermal bridge between the foundation and the slab. The footing and stem wall have just been poured. I think there has been a mis-connect between my contractor and myself because it looks like he is going to place 2" thick rigid foam only in the space between the footing and the slab (i.e. the 4" slab will be "faced" with 2" thick rigid foam...

Asked By ron marsh | Oct 22 14
9 Answers

“Air-sealed” can light retrofit vs. Tenmat cover in attic?

I’m planning some air sealing work in my attic. I’ve got a bunch of recessed can lights to deal with, and I had been planning to use Tenmat rock wool light covers on the attic side. This would involve caulking (say, Tremco acoustical sealant) or foaming to seal the Tenmat cover, plus taping up any cuts to allow for electrical wires, etc. After first going into attic, pulling back existing insulation, sweeping the area clean, etc.

Asked By andrew c | Jun 22 14
1 Answer

Interior insulated cornice for use under low-heel roof trusses?

Has anyone found, used, or developed an interior insulated air-seal cornice for the wall to ceiling connection below a "low heel" truss eave condition that does not accommodate full attic insulation thickness?

Asked By Albert Russell | Oct 21 14
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