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1 Answer

Kraft paper with flash and batt

I live in Virginia and I have a minimum of one inch of foam board plus spray foam in my old 2x4 walls and am about to install the fiberglass insulation. I bought R-13 insulation with Kraft paper. Should I take the kraft paper off when installing the insulation?


In Green building techniques | Asked By Duane Barron | Nov 2 14
11 Answers

A very low addition...

We've been contracted by a repeat client to build a small dining room addition (11' x 12') attached to a contemporary ranch in Maine. Due to very difficult access issues, the addition has to be supported on sonotubes. Bottom of joists (2x10 with fg batts) will only be 2-3 inches over grade.

In Energy efficiency and durability | Asked By ron letourneau | Oct 29 14
6 Answers

Radon mitigation or ERV for old home with dirt wall basement?

Home was built in 1935 and has 5' dirt and rock walls with a small crawl space above that to the bottom of the upstairs floors which are hard wood when your in the in the basement. Radon measured at 7.7 upstairs above that space. I have a thermopride oil furnace down there also. Radon guys telling me it could cause neg. pressure situation with possible back draft or pull exhaust fumes out of the furnace in the basement area. There is an open walking area the size of a regular sized room where the stairs come down and the furnace and water heater are all easily able to work on

In General questions | Asked By Scott Van Der Veer | Oct 30 14
1 Answer

Insulated office inside a larger building

I have a large structure that is well insulated (50x80 with 18ft ceiling) and I am building a 14x30 office inside of it, with 8ft ceiling. The main building will be conditioned at 55-60 during winter and 80-85 during summer. The office will be conditioned to 72 degrees year round.

My question is about vapor barrier on the office. I am insulating the office walls to R19 and filling the 2x10 ceiling joists with blown cellulose or fiberglass batts. Should I use a vapor barrier on the office and if so, to the inside or the outside?


In Green building techniques | Asked By D Badger | Nov 1 14
1 Answer

Is there a frost risk with underslab inslation?

I was talking with a fellow builder the other day and he asked me if I was worried about frost getting under my slab on grade houses because I use 2" xps insulation under my slabs. I also install 2" xps down four feet vertically along foundation walls. His thoughts were that heat loss from the house often keeps underslabs warmer and frost out.

I am in zone 6.

Your thoughts....

Your thoughts

In General questions | Asked By kye ford | Nov 1 14
4 Answers

Minimum R-values for exterior foam for 2x6 walls

I am building an Arctic entry with 2x6 walls, what is the minimum R-values for exterior foam over my OSB sheeting and house wrap to reduce the chance of moisture accumulation in the walls. I live in Wasilla Alaska, which is zone 7 with about 10,500 Annual Heating Days.

After completing the Arctic entry plan on removing siding and retrofitting all outside walls.

Thanks, all help/info will be appreciated

Craig Steinman

In Energy efficiency and durability | Asked By Craig Steinman | Oct 30 14
5 Answers

How to seal 4" EPS foam at slab edge (radon concerns)?

Basement concrete 4" slab to be poured on top of 10mil poly, 4" EPS (2 layers staggered seams), and gravel at bottom with perimeter drains connected to vertical radon vent pipe. Building in a high radon zone, will the poly be sufficient covering the 4"x4" foam perimeter strips not covered by concrete at the slab edge? Should I be tapering the foam edge instead of keeping the full width of 4"x4" strips?

In GBA Pro help | Asked By e c | Oct 29 14
4 Answers

Pipe leak in basement

I am finishing my basement. So far i have installed on the floor a layer of plastic, 1" of XPS insulation taped at the seams, and then a floating subfloor. Yesterday one of my pipes sprung a pinhole leak. The water ran down the wall and got stuck between the plastic and the foam. It ran to the other corner of the basement where my sump pump is located. I can lift up a little bit of the subfloor and insulation in one corner to dry it out but most of it is impossible to move without tearing it out.

In General questions | Asked By Andrew Sirianni | Oct 31 14
8 Answers


We are building a new house in MN (6b), considering various wall systems, and trying to get a handle on the pros and cons of each. Thus far we have:

SIP Pros
- Better known construction method, easier to find carpenters, ...
- Well documented construction details

- Seems like it would be easier construction than SIP.
- Easier to get all details correct.
- Provides significant interior space in attic for ducting, extra room, storage areas, etc.
- Chemical elements (foam, osb, etc) on outside of air/vapor barrier


In Green building techniques | Asked By Walker Angell | Oct 21 14
10 Answers

Steel frame home insulation

Climate zone 2
Ventilated Attic
We plan to use 3" polyiso on exterior walls, taped, with an air gap and steel lap siding.
Plan is to use 6-8" of polyiso on attic floor, and also putting HVAC system in conditioned space.
Radiant barrier on purlins with metal roof.

I'm looking for comments, concerns and advice on whether this amount of insulation is adequate?

or any other thoughts on this approach or things to consider with steel construction.


In General questions | Asked By J B | Oct 28 14
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