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2 Answers

Is there a system that uses 2" polyiso for the wall and 3" for the roof that could be considered energy efficient for zone 6?

Is there a way to construct an energy efficient home for Northern Vermont using 2" polyiso walls and 3" in the roof? There are 3/4" t+g pine boards on the interior, an aluminum vapor barrier, polyiso, stapping and clapboards. How does this work in zone six? Am I missing something?

In Energy efficiency and durability | Asked By Luke Thompson | Mar 24 16
1 Answer

Do I need to worry about kitchen cabinets creating vapor trap?

I have 2" of faced EPS on the exterior of my walls. Will installing kitchen cabinets on an exterior wall in the conventional fashion create a moisture trap? The cabinet supplier is going to measure in the next couple days and then order cabinets. If I need to back-ventilate the cabinets, I need to specify that now so they can account for it.

In Energy efficiency and durability | Asked By Reid Baldwin | Mar 25 16
2 Answers

Certification for re-purposed polyiso. Manufacturer is unkown

The Farifax County code in which I live is as follows:

N1101.12.1 (R303.1.1) Building thermal envelope insulation.

In Building Code Questions | Asked By frost patrick | Mar 24 16
8 Answers

To foam or not to foam? — Basement insulation help desperately needed

I have been actively researching this topic for quite some time, and I feel that every time I finally determine the "proper" way to do it, another piece of contradictory information pops up. I am trying to determine correct method to insulate my basement walls. My home was built in 2007, and there is currently 2" of XPS surround exterior of basement. All of basement walls are below grade. Going to be framing with 2x4 studs. I believe that I should be aiming for R20 total? Is that right? 15/19?

In Energy efficiency and durability | Asked By Trace | Jan 13 16
3 Answers

Does anyone have experience using an electric boiler with integrated instantaneous water heater?

We are considering the Combomax Ultra 12, which is designed to supply all the hot water required for hydronic space heating and domestic hot water (see http://www.thermo2000.com/content/en-us/s2_produits/combomax-ultra.aspx#). I haven't been able to find any reviews on-line and would be very interested in views of pros and/or home owners who have experience with this product or even a similar combo product. Thanks for any information or advice you might be able to share with me!

In Energy efficiency and durability | Asked By Barbara Secker | Mar 23 16
6 Answers

Need advice on closing in porch

My house is in the SE Texas Panhandle, in zone 3B, but only 15 miles from Oklahoma (zone 3A) and also only 15 miles from the majority of the panhandle (zone 4B). So we have a very mixed climate that in my lifetime I have seen range from -15 degrees to +115 degrees F. Some years it is quite dry and some years quite rainy and humid.

In General questions | Asked By Linda Wolf | Mar 21 16
19 Answers

How important is it to tape both layers of foam?

Hi guys,

I am installing two layers of 1-1/2" fiberglass faced poliso. I purchased some cheap tape that I had thought would make a good seal on the seams. However, now that we've put a layer on, it is obvious the tape isn't going to do the job. So now I have a lot of left over tape and facing the fact of buying more expensive tape to do the job right.

In Green building techniques | Asked By Clay Whitenack | Mar 18 16
0 Answers

Recos for solid cellulose densepack contractors in MA?

I know bunch of us here are MA folks. I have one contractor, who has done densepack of some of the walls, but I think they are way overpriced. I want to densepack cathedral ceilings and want to get someone else to quote me. Any recommendations?

In General questions | Asked By Apollo S | Mar 24 16
7 Answers

Spray foam insulation and barrier?

Getting ready to start construction on new home. Slightly over 1300 sq ft. We live in Oklahoma, Zone 3A. 2 x 6 exterior walls with OSB sheathing and 3/4" wood siding. Cathedral ceiling with 12/12 pitch, 2 x 12 rafters on 24" center. 24 ga galvalume roof, wood frame/high efficiency windows. Trying to make sense of the spray foam vs high density batting for ceiling and the best method for 2 x 6 walls.

In Green building techniques | Asked By Scott Smith | Mar 24 16
8 Answers

Advice for insulating a new build unfinished basement?

We are planning on tearing down and rebuilding our home which will be a 4500 sq ft bungalow with an attached quad garage. Finishing the basement is not possible immediately, so what is the best choice to economically insulate the basement walls without having to drywall up? Would thick rigid foam be the only option to get R20? Is it allowed to just put up rigid foam with nothing else on the foundation wall?

In Building Code Questions | Asked By Reginald Chin | Mar 22 16
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