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3 Answers

16 ga. or 18 ga. wire for lighting circuit?

LED lights are 5 watts.
Do we still need 12 ga or 14 ga wire?

Asked By C Darwin | May 7 15
3 Answers

Is a radiant barrier a good idea for rigid foam under siding?

I have posted many details and questions in this separate post: http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an...

Asked By Chad B | May 8 15
7 Answers

Building a home - to code?

Hello all,

Thanks for taking the time to read my post. I am in the process of designing a small (~ 700 sq. ft.), off-grid house. My intention is to do as much of the design and construction as possible with my own head and hands.

I've been a car mechanic for 10 years, and so have a good understanding of the basic principles of electricity (the house will use 12V wherever possible), HVAC, plumbing, etc. However, I don't have much in the way of hands-on experience with construction.

Two questions (among many) occur:

Asked By Tomas Gray | Apr 23 15
3 Answers

What causes condensation in every window in the house?

Recently we built a new home with stucco exterior and icynene spray foam insulation. In the winter months condensation develops in every window of the house even the front door. What could be causing this problem? I suspect the heating and cooling contractor may have used the bubble wrap underneath the house to wrap the heating and cooling distribution system. Could this be the problem?
Thanking you in advance for your cooperation and advice.

Asked By Joann Mullins | May 8 15
2 Answers

Looking for curbless shower floor in concrete slab details.

I've heard that builders take different approaches to dealing with the lowered area of the slab. Some form the depression intergal with the rest of the floor while others block it out and pour it later. I'm currently laying the underslab dwv system and building a box that will provide a void in the fill and EPS to install the p-trap and drain piece later at the correct height. Also, I hope the detail would show how the EPS is handled under the shower area. If using 2 layers of 2" EPS are they both set down 2" to maintain thickness of the foam and concrete? Thanks for any info on this.

Asked By Chuck Jensen | May 7 15
12 Answers

Suggestion for making a 30 year old home more efficient while roof and siding are off

We live in Columbus, Ohio and have a home built in 1986 with the following floors. Floorplans and photo are attached as an FYI.
- Basement: 740sf finished, 250sf crawl space
- 1st floor: 1000sf
- 2nd floor: 800sf

Asked By Chad B | Apr 25 15
4 Answers

Issue with HardiBoard over exterior foam and strapping

I will be building new soon and found a builder willing to do 1.5-2" of external foam (zone 5) our plan is either brick veneer or a craftsman style with hardiboard siding. The plan was to use strapping (1x3 - 1x4) over the foam for a place to nail the siding, however, the siding contractor rightfully pointed out that hardiboard is fragile and if struck between the strapping the hardiboard could snap. His preference (and the manufacturer specified) method is to have a continuous backing under the hardiboard.

Asked By Michael Donahue | May 7 15
10 Answers

Calling all structural engineers

I'm like the opinion of a structural engineer.

I'm reviewing a book that includes this statement: "Rigid insulation is made from plastic foam (polyurethane, isocyanurate, or polystyrene) or fiberglass, pressed or extruded into panels. It ... may have some structural value when used as a continuous layer on exterior structural walls."

My first response to this statement is: Really? I'm doubtful.

So here's my question: Do engineers ever take into account the contribution of rigid foam insulation when making structural calculations?

Asked By Martin Holladay, GBA Advisor | May 6 15
51 Answers

Odor problem in attic after spray foam applied


I am looking for any advice or suggestions with regards to a situation we are now dealing with in my home after changing our vented attic to a non-vented attic or semi-conditioned space.

Asked By Dave | Jul 11 10
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