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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

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
7 Answers

Closed-cell spray foam versus dense-packed cellulose - Noise control in a PassivHaus

This is a comment rather than a question.

In our pre-certified PassivHaus in northern NJ, we have 10-inches of densepack cellulose and 2-inches EPS in the walls, and 10-inches of closed-cell spray foam in the roof.

We've noticed that the noise attenuation through the walls is much greater than through the roof.

Most of the noise getting into the attic comes through the roof, which is asphalt shingle over plywood decking on 2x12 rafters, with the space between the rafters filled with 10-inches of the closed-cell spray foam.

In PassivHaus | Asked By Len Moskowitz | Oct 15 14
5 Answers

An outside, completely isolated, balcony column structure

In an outside, completely isolated, balcony column structure that must be finished in stucco and built using steel studs, would it be possible for any moisture damage in the inside of it if we were able to completely seal the inside from the elements? In a 4c zone, applying stucco to acrylic panels to make a stand-alone column.

In General questions | Asked By peter mare | Oct 20 14
2 Answers

Gluing rigid insulation to interior of roof sheathing

My home is in Northern Michigan and I wish to insulate an attic that has storage trusses and considerable open spaces behind the perpendicuilar truss members. There is soffit venting around the entire attic perimeter. The attic floor is insulated to R 30. (Peaked roof built over original flat roof)

My first choice was to spray polyurethane to the cathedral underside of the roof sheathing, however I am having difficulty scheduling a contractor, most of whom have bigger jobs they are chasing, so I am considering other options.

In General questions | Asked By Wes Benner | 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...

In Energy efficiency and durability | Asked By ron marsh | Oct 22 14
12 Answers

Thermal energy storage

~3900 square foot house.

I am thinking of building a water based TES tank using ICF in a crawl space.

The plan would be to use RV antifreeze in an active (pump) circulating heat exchanger that sits at the bottom of a tank of water. Domestic water supply would pass through another heat exchanger that sits at the top (for stratified water column effects) inside this tank and preheat water for radiant hydronic boiler and domestic hot water.

I was thinking 12'x12' @ 6' tall for a 864 cubic foot / 6463 gallon tank.

In Green building techniques | Asked By Jim Pancanke | Oct 21 14
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