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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!

In Energy efficiency and durability | 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.

In Energy efficiency and durability | Asked By Alan B | Oct 23 14
8 Answers

Attic insulation — existing

I have a 1800 sq. ft. ranch home built in 1969. Climate zone 5. Existing attic floor/ceiling area has a layer of 3" fiberglass insulation with vapor retarder facing the heated space. The second layer of insulation is a 3" layer of fiberglass with vapor retarder facing the attic area.

Both layers have been installed inside the joist bays and stuffed very tightly at the top of wall/ceiling intersection-no soffit vents in place. The roof has box vents and gable vents in place for ventilation.

In GBA Pro help | Asked By bob prince | Oct 22 14
15 Answers

Window U-value comparison to wall R-value and window replacement

We have an 1870s Victorian farmhouse that doesn't have insulation in the walls, and to keep it simple, we cannot add insulation in the walls without going to great expense, more than we can afford.

In General questions | Asked By Keith Miller | Oct 20 14
3 Answers

Large structure with sealed attic / fiberglass

I have a 48x75 post frame structure with a metal ceiling. Prior to putting up the metal ceiling I installed a 6mil plastic vapor barrier. The entire interior is encapsulated with the 6mil plastic under corrugated barn/ag panel metal. I want to blow R60 into the ceiling, but my metal spans 8.5'. I am worried about the weight of cellulose. I used R-panel on the ceiling for a higher load rating and span, but I still think R60 with fiberglass would be much lighter.

In Green products and materials | Asked By W Ahrens | Oct 22 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.

In Energy efficiency and durability | 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.

In Energy efficiency and durability | Asked By Jeff M | Oct 22 14
1 Answer

“Radon Mitigation Systems” article

“Radon Mitigation Systems,” June / July 2014, pg 86 -87: Holes on pipe.

I look back at the article from June / July 2014, “Radon Mitigation Systems,” page 86 -87, and notice the drawing with the holes on the pipe point up instead of pointing down?

I was wondering, is this so people that read the article would see what was meant by the perforated pipe?

In General questions | Asked By karl neemann | Oct 23 14
5 Answers

Double wythe CMU vs. Thermomass

After living in Europe for several years I have become a fan of concrete. I build in the Southeast and have mainly used concrete commercially and as stem/foundation/retaining walls and for slabs in residential.

In Green building techniques | Asked By leo kloop | Oct 22 14
5 Answers

How does the attic fan work? And can you use it in the winter?

We bought a house early this year in northern Virginia that has a attic whole house fan. It h's a pulley on it that closes a box on the fan or opens it. we believe that one way makes the air blow in the attic and the other to push the air down into the closet under the stairs to the bottom level of our home. We had it where the air vented to the attic all summer but not sure that we did it correctly. Now it is getting cold and we are using the fireplace and not sure if we should run the fan or not. The fan is attached to a thermostats in order to adjust it.

In General questions | Asked By Aleasha Jeffries | Oct 22 14
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