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7 Answers

Overwhelmed with Insulation Choice in NE Texas with a 3:12 pitch

We purchasing a 3000sf 1950's ranch style house in NE Tx. I really need your advice narrowing down the best insulation for us.

Problem: 3:12 pitch, no insulation and 2 wings of the house only have tiny access hatches that are blocked by ducts, and it needs a new roof in the next couple of years. Opportunity: we can seal up the openings and insulate it any way needed when we replace the roof.

In Energy efficiency and durability | Asked By Tonya McClelland | Mar 22 12
3 Answers

Dirt crawlspace insulation

I live in northern Minnesota. The house I purchased has a large bedroom, half of which is an addition to the house. It gets fairly cold in the room during the winter and I am looking at better insulating it. The addition portion has no slab or foundation under it. It was basically built as a fourseason porch with only footings. There is access underneath from outside with enough space for me to comfortably crawl underneath. It has dirt floor, batt insulation in the floor joists and a flexible/insulated heating tube going to the far end. No other pipes or wires.

In GBA Pro help | Asked By Nathaniel Hughes | Mar 22 12
4 Answers

Polyiso directly over Tyvek stucco wrap vs 1/4" shims between

I am a remodeler, project is my own whole house remodel in North NJ (Morristown - Zone 5). After reviewing your excellent information and blogs the envelope planned is:

In Green building techniques | Asked By Carlton Bruen | Mar 22 12
1 Answer

How to calculate Floor Insulation Effective R-Value

I have a 2x12 floor system with R-19 supported by spring wires every three feet or so. The insulation is 5" from being in substancial contact with the floor. What is the effective R-value and what publication can I point to for substantiation.

In Energy efficiency and durability | Asked By Tyson Pischel | Mar 23 12
8 Answers

EPS Foam on Exterior with interior vapor barrier?

I am gong to be re-siding my house (cedar) and am considering adding 1" or 1.5" of EPS foam on the exterior. My concern is that the current R13 insulation (2x4 walls) has a kraft faced vapor barrier. I know that I can't use XPS foam on the exterior because it is impermeable, but I know that EPS has a higher permeability, so I was hopring this would work and allow drying to the outside. I will be using a rainscreen over the foam. I am in Portland, OR which is in zone 4.

Would this work? Is it even worth adding the foam to an R13 wall?

In Green building techniques | Asked By David Fischer | Mar 10 12
20 Answers

Foam Under Monolithic Slab/Footing

Inspired by a recent blog post by Martin, I'm wondering if anyone has attempted to form and pour a monolithic slab/footing with foam at every facet, as depicted in the section sketch below. Pieces A and E are straightforward enough. Piece B calls for a lot of fussy smoothing at the bottom of the trench. Piece C looks like a serious pain in the neck to fit and hold in place. Piece D is a fantasy.

In Green building techniques | Asked By Ray Sten | Mar 15 12
14 Answers

Please review our double Stud Wall over floating slab plan

Since it will be a couple of weeks before GBA posts a recommended wall section, I would like to get your critique of the wall section and foundation plan drawn by my architect. We are still in the early stages of design but have a tight timeline to get the house designed and started.

Thank you

In GBA Pro help | Asked By Elizabeth Kormos | Mar 16 12
1 Answer

I am looking for a listing of ICC accredited labs who are experienced in testing housewrap material for R-value

I am new to the building construction industry and have found a product that I think can improve insulation characteristics. I understand for it to be used it must be tested by an ICC accredited laboratory. Their listing has thousands and thousands of accredited labs but they do not list them by product category. I'm asking if anyone can direct me specifically to one that could help me get this product tested.

In General questions | Asked By David Bechtol | Mar 22 12
1 Answer

Are there different conditions when to use low-e interior versus exterior reflective windows?

The reflection from my neighbor's low-e window is melting the siding on my house. I have heard that it would make a difference if the south side of his home had interior reflecting windows rather than exterior reflecting windows. Is that true? We live in Connecticut so we obviously experience warm temperatures in the summer and cold temperatures in the winter.

In General questions | Asked By MaryAnn Brown | Mar 21 12
3 Answers

Sill gasket

I'm currently planning on using an EDPM gasket under my sill plate (new construction). I'm also planning on using sprayed close cell to fill/seal the rim joist on the basement side. Since the main purpose of the sill gasket is air-sealing, is it really necessary if I do a quality job with the closed sell spray?

In GBA Pro help | Asked By Jim Orasky | Mar 21 12
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