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1 Answer

Due to aesthetics, R-20 (4 1/2 inches of rigid foam) above the roof is my limit

Due to aesthetics, R-20 (4 1/2 inches of rigid foam) above the roof is my limit. Would Roxul plus an airspace in the rafter bays be a good choice for the remainder of the needed R-value?

Jesse, 80% of home is concrete slab with remaining 20% being crawl space I closed in - conditioned basement. In a high water table area with no vapor barrier under slab or crawl. De-humidifier runs constantly.

I plan to include air space in rafter bays under sheathing along with batt insulation for remainder of needed R-value. Is an airspace necessary with R-20 foam above roof sheathing?

In Green building techniques | Asked By cameron morris | Jul 1 14
8 Answers

Another Hole(s) in the... Wall

My Northern zone 5a home can't be a Passive House (PH) because it was built in the 50's. But I'd guess that imitating PH practices where possible as projects are done will help the house be the best it can without a gut rehab.

In PassivHaus | Asked By Gordon B | Jun 23 14
1 Answer

Crawl Space

Hello, I need help! I have a small one story single family home. We removed the old/damp insulation and I need to know if I should close off the vents and put a dehumidifier in the crawl space? I do have a vapor barrier on the stone ground, but there still is moisture and some signs of mold! We did put a sump pump in there last summer. What should I do, this property is in Annapolis MD.

In General questions | Asked By Lynn McCreary | Jun 30 14
4 Answers

Insulating I-joist cathedral ceiling with Roxul

I have decided to use Roxul to insulate my cathedral ceiling constructed of I-joists on 24" centers.
The Roxul should be encapsulated on all sides.
I will be leaving a ventilation cap at the top of the I-joists, utilizing the flange as the spacer.
I was planning on using the steel stud version because it is 24.25" wide.

I first thought of using 1" XPS as the air sealing, cut to fit between the webs, caulked and taped.
I was wondering if using something like Tyvek sealed and stapled to the underside of the flange instead of the XPS?

In Green building techniques | Asked By Aaron Gatzke | Jun 28 14
10 Answers

Do exterior solar screens provide radiant barrier to heat loss?

I live in Baltimore. I have been thinking about maintaining high solar heat gain in my windows for winter benefit. In the summer, when I need to put up insect screening anyway, my thought is to use one of those dual purpose insect screen and solar screen (e.g. like Linay type). I don't see any measured SHGC on the solar screen websites but there are apparently 70-90% solar radiant heat reduction options. I like the idea of cutting down the radiant heat before it reaches the window pane to reduce cooling load.

In Green products and materials | Asked By Richard | Mar 24 10
0 Answers

How to add Pic's

Can anyone tell me how to post a pic in the responses or questions section? I have an IPad and have some pics I'd like to post. Is there a way to add an attachment?

In GBA Pro help | Asked By kye ford | Jun 30 14
2 Answers

Would using spray on foam as insulation allow me to avoid the need to use any drywall in my exterior walls?

Would using spray on foam as insulation allow me to avoid the need to use any drywall in my exterior walls if I am using tongue and groove wood for interior walls? Also is there any interior treatment that can reduce thermal transfer through the 2x6 studs?

In Green building techniques | Asked By Stan Soper | Jun 30 14
4 Answers

Are there passive solar designs that have large north side windows?

Our land has spectacular bluff view, which we want to enjoy from inside, so having some large windows facing the bluff are a desirable feature for our future home plans. Unfortunately the bluff faces NORTH. We would like to use passive solar design, but from what I have read, windows need to be kept to a minimum on the north. What can we do to maximize solar heat gain without sacrificing our view?

In Energy efficiency and durability | Asked By Kirk Smith | Jun 29 14
14 Answers

What's the best basement flooring system?

Remodeling a 1500sq.ft. walkout that previously had carpet on the concrete. We want to do the kitchen and bathroom in tile or stone and the rest of the area in wall-wall carpet. The only ptroduct I've found thats meets my requirements are Delta Fl with t&g plywood for the carpeted area and Schluter®-DITRA-HEAT for the tile/stone area. Not fond of the t&g plywood in the basement as everything else will be mold proof. Are there other options beside inorganic individual tiles or is the Delta Fl system reliable?

In General questions | Asked By Jeff Dieterle | Mar 8 14
3 Answers

Drywall on 24 inch o.c. framing?

Are there any issues with using 1/2" drywall on 24" o.c. framed walls?

In Energy efficiency and durability | Asked By Jerry Liebler | Jun 26 14
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