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3 Answers

Roxul vs. Thermafiber?

Anyone know if there a significant difference in quality and/or price between Roxul batts and Thermafiber batts?

I've ordered Roxul Comfortboard (for the exterior of the house) which is being shipped from Ontario to western Wisconsin. I now see it MIGHT be more convenient to source Thermafiber batts (for the interior) in this part of the country.

Thanks,
Ed

In Green products and materials | Asked By Edward Krause | Aug 9 14
1 Answer

Mineral wool boards below grade and termites

My house's structure is made of wood and there are subterranean termites (non-formosan) in my yard and area. I am planning to excavate and insulate the slab perimeter in the interests of saving on heating, but am worried about creating a termite highway.

I figure XPS is right out, and I'm not sure about termite-treated EPS either. The availability, price per R, and ease of installation are attractive, but since the advertised termite resistance just comes from a chemical treatment, I worry that it will fade or leach out over time.

In Energy efficiency and durability | Asked By Nathaniel G | Aug 8 14
9 Answers

Whole home insulation ideas

In addition to my other post I would like to know about the best approach for certain areas of the house here are my concerns

ATTIC: 2" of open cell foam along bottom cord of trusses to seal drywall, also spray foam where top plate and drywall come together, also where insulation baffle meets top plate. 12 inches of blown cellulose on top of the foam
QUESTION: Is this a good plan to seperate the attic from the conditioned part of the house?

BONUS ROOM OVER GARAGE: 3" od open cell in ceiling of garage to keep floor warm

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 8 14
9 Answers

Spray foam roof and vapor barrier

I have a Cape Cod style house that we had the roof sprayed with Open Cell foam. We plan to finish off the upstairs for living space. My question is that If we plan to use liquid vapor Barrier primer/paint do I need to paint all the foam, or can I get by with just spraying the drywall only. Do I need to spray behind the knee walls or will the drywall on the knee walls be sufficient? We do live in central Wisconsin.

In Energy efficiency and durability | Asked By Dave Meyer | Aug 3 14
4 Answers

Detailing bottom of Roxul Comfort board IS

How are those of you using this product detailing the bottom of the wall where the Roxul is exposed?

I noticed on one post about a project in BC, they used a perforated galvanized channel to encase the bottom of the IS. Does anyone know where to source a channel like that?

I'll be using 3" Comfort board over 1/2 CDX sheathing, over 3/4" x 3" furring strips, then cedar shingles.

Thanks!

In Green building techniques | Asked By Edward Krause | Aug 8 14
2 Answers

Batt insulation for bonus room... installed correctly?

ok. I live in the South (Lower Alabama) and my bonus room above my garage, gets warm during the summer. I went in the attic today to see how the insulation was installed and I noticed that it is Paper towards the room (insulation towards the hot attic space). I read a few articles where basically is states that it doesn't matter (or depends) on which way the paper faces.

In Energy efficiency and durability | Asked By Nathan Jones | Aug 8 14
8 Answers

Buildability vs. durability

I'm going to be building a 28x40 (aprox 1500sf living) chalet style house in upstate NY CZ6 (design temp 6f) it will sit on a walk out basement (one narrow end walk out the rest under ground) I am going to put pex in the slab even though I don't currently plan to ever need it warmer than 55 or so down there.

Been reading on the subject quite a lot, and think that the pretty good house concept you guys have come up with is a great idea, and should get me in a balance point between up front cost, and monthly utility bills.

In Energy efficiency and durability | Asked By Trevor Chadwick | Aug 4 14
12 Answers

Insulation vs. air flow extra expense

Hi, I’m going to have a new house built and am confused on where to spend additional money in regards to insulation and air flow.

I have talked with many builders and most offer a “standard” solution involving fiberglass batts in walls for insulation and no air control layer (other than drywall or caulking holes that they find from blower door testing).
If I am interested in anything better it will cost me more money.

I understand that “batt” insulation can be problematic in regards to having it installed correctly.

In General questions | Asked By Ani Brown | Aug 6 14
2 Answers

Would metal roofing (say Imperial Rib type profile) on decking and horizontal purlins work for venting a roof assembly with sealed fibrous insulation-filled rafter bays?

The main question is whether the air space provided by the metal ribs would provide adequate air flow. If not, how about vertical 2X 'purlins', forming site-built insulation baffles that would be insect screened at both ends?

In Green building techniques | Asked By Michael Roland | Aug 7 14
4 Answers

Vapor retarders for double stud cellulose-filled wall assemblies

Following up on last month's blog about building codes, am I correct that the code allows interior vapor retarding with latex paint on sheet rock? Also, does the vapor permeability of ZIP sheathing prevent inner wall condensation without the use of exterior foam?

In Building Code Questions | Asked By Michael Roland | Aug 7 14
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