Q&A: A Forum for Green Building Experts and Beginners

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

Please register for a free account or sign in to ask and answer green building questions.

If you want to post a question, the usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration: Under the box labeled “More explanation,” look for the words “File attachments.” Click that, and you should be able to attach a photo.

Thanks for joining the conversation!


0 Answers

Mud sill seal

In the FH article about air sealing a mud sill they used a EPDM product. The mud sill was 2x6 but it looked like they used the gasket intended for 2x4 material. I believe the product is available in both 2x6 and 2x4 widths and was wondering why the intended product was not used. If the 2x4 gasket is acceptable it would save some $.
Thanks.

In GBA Pro help | Asked By Robert Brown | Jan 22 15
0 Answers

curious about anyones experience with zip system liquid flash

I'd like consider this with my zip project, just seems to me a liquid applied sealant like this would be less vulnerable to any long term failure (possibly with tape). I know martin did a tape test some ago, but again i have had quite a bit of hands on with the tape and im not all the way there that its a 30 year product. Im also curious whether or not there is a primer option that might insure optimum adhesion.

In General questions | Asked By kevin freeman | Jan 22 15
0 Answers

Foundation Details

Hey,

New to here and appreciative of all the learning I've done pouring over all the info.

I have a couple questions related to designing the foundation for my home.

I want to have a perimeter concrete foundation (either frost-protected or to below frost line, haven't decided yet) and ideally a finished earthen floor on grade for passive solar use (and less hard on the feet than concrete). I'm wondering about a couple of the details:

In Green building techniques | Asked By Moses Draper | Jan 22 15
6 Answers

Is the Airtight Drywall Approach obsolete?

After months of reading blogs here, I was just about sold on using the airtight drywall approach for all areas of my home that were to be re-drywalled. The main area being the entire attic ceiling which will then have cellulose blown in above it and vapor barrier paint applied over it. After asking my builder and insulator to use the Air tight drywall approach (and offering to pay a significant premium to do so), the insulator sent me this article: http://foursevenfive.com/4-reasons-why-airtight-drywall-is-obsolete/

In Green building techniques | Asked By Ryan Griffin | Jan 21 15
3 Answers

Sulphates in cellulose insulation

I'm within a few weeks of dense packing the walls of the house I'm building with cellulose.

The installer uses cellulose with a "blend of non-corrosive borate and sulphate fire retardant additives."

Should I have any concerns about the sulphates? I'm waiting to hear back from the manufacturer about which sulphates are used.

Any other things to look for (or avoid), with respect to cellulose, would be much appreciated.

In General questions | Asked By Graham Fisher | Jan 22 15
1 Answer

What is the R-value?

I found an insulation recycler that has 1.5" polyiso for the price within my budget.
What I am trying to figure out, since Googling it does not produce results, what R value should I expect out of NRG Barriers 1.5" polyiso?

In Green products and materials | Asked By Apollo S | Jan 22 15
9 Answers

20-foot vaulted ceiling & 1970s sagging insulation - need insulation retrofit advice

One of the additions to the house was a huge 20X24 living room with 20' vaulted ceiling. I guess they were all the rage in the 70s and so was insulation that is now sagging. I was looking with IR camera and I could just see these cold spot areas behind drywall where insulation has sagged. That room also drops 2 degrees for every hour, unlike the rest of the house where temps drop 1 degree per hour.

In Energy efficiency and durability | Asked By Apollo S | Jan 6 15
3 Answers

Low expansion foam or airtight tape for windows?

Hi all. One more air sealing question. Is there a preference here between using low expansion foam to seal the gap between a window frame and rough opening vs. tape? I've heard both methods referenced here. Should I consider doing both, or is foam alone sufficient?

In Green building techniques | Asked By Ryan Griffin | Jan 22 15
1 Answer

Persistant smell in house dense packed with cellulose

We insulated both attic and walls with cellulose. One bedroom that has the attic staircase in the closet develops an odor that the customer says "smells like the day you were installing it". When you open the closet there is no smell, so it is not coming down attic staircase. Customer has bought covers for air conditioning ducts that are in the ceiling. Room is heated by a boiler with recessed hydronic registers under windows. Pipes run through the exterior walls that are now dense packed. Shoe molding is missing from baseboard.

In General questions | Asked By Walter Gayeski | Jan 21 15
8 Answers

What are your thoughts here?

This does not really matter ultimately but its an interesting thought exercise.

In General questions | Asked By Alan B | Jan 19 15
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!