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

[Click map to enlarge]

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

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!


3 Answers

What is the calculation method to determine the actual BTUH output of a hydronic radiant floor?

We are looking for a mathematical calculation for determining the actual btu output of a hydronic radiant slab floor in a basement. Any assistance is greatly appreciated.

Thanks.

[The author of this question has asked for his name to be omitted.]

In Mechanicals | Asked By GBA Team | Jan 16 15
9 Answers

My question is, how do I properly insulate from the inside and prevent a mold or rot issue when there is no sheathing?

Hello everyone. I have an insulation challenge that I could use guidance on. I am located in the Midwest zone 6 and converting a 22'x25' 1950 detached garage with a concrete floor into a heated workshop.

In Energy efficiency and durability | Asked By Ell Aire | Nov 8 14
14 Answers

Attic / roof air sealing and insulating

I am a novice DIY trying to avoid mistakes. This house is in Iowa.

I have a house and am renovating before occupying. The first goal is air sealing and the first project was the rim joists.

Now I am preparing to seal and insulate the attic, which I think in this case would require sealing and insulating the roof.

In General questions | Asked By Erich Riesenberg | Feb 13 13
29 Answers

Polyiso for basement

Morning all

I am about to embark on the basement insulation. I have a question about polyiso. After much reading I was so sure about putting xps 2" rigid foam against walls and rim joist.

I read the gba, several other forums and as I understand, the steps are - clean the basement walls, clean rim joist, place rigid foam, seal with great stuff, place xps with foam glue on walls, tape the seams, seal the edges with great stuff, leave a inch gap and frame with stud walls.

In Green building techniques | Asked By sr kod | Dec 20 14
1 Answer

WRB recommendations for interior fireplace surround

I am redoing a fireplace surround with synthetic stone and need to know what to use for a WRB under lath mesh and scratch coat

In Green products and materials | Asked By John Bertelsen | Jan 19 15
2 Answers

What is the best section detail for a recessed porch over an occupied space?

I am desiging a recessed porch off a second floor master bedroom. The porch/MB is above the garage.

I am looking for waterproofing and insulation details for this condition.

Thanks in advance.

Erik

In Energy efficiency and durability | Asked By ERIK MAGNUS | Jan 12 15
4 Answers

Question on cut-and-cobble rigid foam in a vaulted ceiling

Hello all,

About a year ago Martin Holladay wrote an article on GBA regarding the practice of cutting rigid foam into 14" wide sections and installing them between framing as a poor man's alternative to spray foam. Being a poor man (frugal is more accurate), I've decided to implement this in our new master bedroom (which was our old garage). We intend to vault the ceiling and removing as many of the old ceiling joists as our village will allow.

In Green building techniques | Asked By Brian Gray | Jan 18 15
0 Answers

Would you be concerned about interior Formaldehyde levels with mineral wool

I was looking at using mineral wool batt insulation between studs in a staged retrofit situation. It looks like most of the mineral wool batts available still use a formaldehyde binder.

I wasn't too worried because the home is very leaky right now and I thought that I might "dilute" out the formaldehyde over a few years before I tightened up the envelope. However, I found this article by Dr. Joe http://www.buildingscience.com/documents/insights/bsi-070-first-deal-wit...

In it he shows/states that :

In Green products and materials | Asked By MIke Truxillo | Jan 19 15
2 Answers

Insulating solid brick house

Hello! I've been reading this forum for awhile now and there's so much good information about insulating I don't know which direction to head in. I have a 1950s ranch in Michigan that is under renovation. I currently have most of the walls exposed and wanted to know the best way to go about this. It's a solid brick (like small cinderblock?) house with furring strips and 2 layers of drywall on the inside. On the outside I have furring strips with vinyl siding.

In GBA Pro help | Asked By Jeff Hogarth | Jan 9 15
2 Answers

Wall assembly (Zip R) for mixed humid

Hey Folks,

My architect has planned a 2x4 wall with Zip R 1" foam sheathing. It will likely have batt or blown insulation. I see a ton of Zip sheathing around here, but I doubt much of it is insulated. Should this assembly hold up in my climate 4A (mixed-humid). I particularly concerned about vapor permanence and drying.

Thanks!

In Energy efficiency and durability | Asked By C. Maglio | Jan 10 15
Register for a free account and join the conversation


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