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4 Answers

So I read the innie vs. outie window article on GBA and decided to go with the innie route as I had already made my R/O to size and didn't have time to fir out the windows before my window installer (friend) showed up. So I have my windows in with flanges against sheathing and they stick out just over 2" from the sheathing. I am putting 2' rigid polyiso on the exterior and butting it into the windows. This means there is no foam showing. Do I need to put peel and stick flashing on the exposed foam before installing it? should I leave it away from the window slightly and spray foam that gap?

Asked By jordan Saunders | Sep 1 14
22 Answers

I was speaking with my passive house consultant the other week, and she expressed concerns about boring critters and subsurface rigid insulation. She had such an experience with some insulation in her garden (It was put in one season and removed at a later time as she got back to completing the project.)
Now, I know all about the ate/termite protection used in these insulation products, but what about larger critters that would love to have a warm dry home?

Asked By Steve Young | Aug 16 14
19 Answers

Hi. I am back and forth on whether I should use XPS (blue board) or EPS for the insulation underneath my slab. I understand the qualities of each regarding water absorption and drying out, but would it (XPS particularly) affect the long term performance to the point where the slab is compromised? I also understand the pollution associated with XPS manufacturing. I have the option of purchasing 6" (house in very cold climate) of EPS (R-24) or 4" of XPS (R-20). The EPS is less expensive per inch, however, I need to pay for shipping which jacks up the price.

Asked By Matthew Michaud | May 2 14
2 Answers

I have a section of my house withe a Cathedral ceiling.

SW Michigan - Zone 5A
~50 lb snow load area
4/12 pitch.
One side of the cathedral runs up to the house.

The current ceiling is (from inside the outside):

Roof is 17' wide and 20' run gutter to ridge.
Timber Rafters - ~6' on center, about 4'x10'
T&G boards on top of the rafters.
About R20 (guessing it is 6-8" thick) insulation.
Roof deck and black asphalt shingles.

I have 2 problems.

Bad ice dams
Noticeable temperature change to the next room. (hotter in summer and colder in winter).

Asked By Ian Osborn | Sep 2 14
20 Answers

I would like to decide on putting in solar panels to reduce energy costs.

I have read about the next generation solar panels not being to far off.

Question: Would it be better to install current solar panels or wait for the new type that will be coming shortly?

Asked By John Alberti | Aug 26 14
5 Answers

Could a roofer possibly give an explanation as to what is occurring near my eave adjacent to a side wall. I have included pics. This has been about 8- 10 years in the making. There is currently a small depression (pic 1875) which is from deteriorating decking, but for 8-10 years there was dripping from underneath the soffitt below where this depression is pic 1871. The water also runs down alongside the house - pic 1869. (This water is not coming from the eave trough.

Asked By eric michael | Aug 30 14
3 Answers

We're building a new 2-story home in central Iowa. It will have a below grade basement with 9' foundation walls. The slab will be about 8 feet below grade.

Asked By Silas Hoeppner | Sep 1 14
10 Answers

Hi,
I am currently redoing the exterior of my house with a new vinyl siding and changing all windows. My house was built in the mid 80's and have 2x6 studs with Batt Insulation and mostly without a vapor barrier... but the insulation is not great, especially the air goes through the house.
My question is what is the best insulation for me to put outside the house underneath the vinyl siding. My windows will allow me to go up to 1 inches of exterior insulation.
So XPS with Typar? Polyisocyanurate (IKO Ener Air )? Others?

Asked By Jason Haché | Aug 29 14
4 Answers

4" of 2 lb closed cell spray foam will go on underside of roof sheathing....so roof needs to dry to outside; hence why I am using #30 felt/tar paper instead of a non-permeable ice & water shield.

However, to get my Class A fire rated system, I need to use an ASTM D 3909 cap sheet over the tar paper. How well is this system going to be able to dry to the outside and will there be any issues with this system?

The roofing material is a synthetic shake; Bellaforte by DaVinci.

Thanks-Eric

Asked By eric Mikkelsen | Aug 29 14
4 Answers

Hello,
I live in the Pacific north west, and will be building a home off the cost of Vancouver island this fall. The house is small, 700 square feet, with a 1 n 12 pitched roof as the design. We have not started construction on the house as yet and we want to deal with the roof in a way that will, of course, provide the best of all worlds.

Asked By Jeannette Sirois | Sep 1 14
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