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5 Answers

IRC 316.4 - Code interpretation on the use of rigid foam as air barrier on backside of attic knee wall

My insulation plans for my attic kneewalls were to install two layers of 2" eps with staggered and taped seams, then install damp sprayed cellulose in the 2x4 stud cavity, followed by 1/2" drywall. I believe that a thermal barrier is required since I have usable attic space, but I am unclear whether this thermal barrier must be installed on both sides of the stud wall, or only the portion of the stud wall that faces the interior of the attic room. The gray area is whether or not the areas behind the stud wall are considered the "interior of the building".

In Building Code Questions | Asked By Rick Van Handel | Oct 17 14
3 Answers

Can we install an HRV in our house now?

Our house is one year old, we live in Vancouver, 5000 sfu on three levels. We have duct venting for our Lennox Furnace, Air Conditioner, and Air filter. I have to run 3 upstairs bathroom fans to avoid moisture forming on the windows. We have only recently learned that the contractor did not install a HRV.

Do I have to install new ducting (which I can only image is a huge job) or can the existing vents somehow be used?

Regards
Mark

In General questions | Asked By Mark Orsmond | Oct 18 14
2 Answers

Self-leveling compound

Hi there, I laid some engineered wood flooring on concrete with Mapei Ultraplan M20 self-leveling compound over a week ago. The bags said zero VOC premixed.

There was an awful sweet/fruity chemical smell when I mixed it. I called Mapei and they said it would go away when dry.

However, the smell is still here. I would have thought the underlayment (AirGuard Roberts 3-in-1) would cut the smell but it's bad.

I need to level plywood subfloors upstairs to finish this job and wondering if anyone can recommend an equivalent product that doesn't stink.

In General questions | Asked By Brooke Beloso | Aug 8 14
34 Answers

Options for high R-value above-grade walls (R-80)?

To make a long story short, my above grade exterior walls need to be at an R value of 80. This is to meet Passive House standards for a new residential house in a very demanding climate.

I am currently planning on using SIP's of some sort. But even the best of those only get me up to around R-50 though. Any thoughts on ways to get to R-80 while still being cost effective and keeping the size of the wall to a minimum?

I have found a number of options myself, but was curious if anyone else had thoughts or suggestions to meet such a high R value for a wall.

In Green building techniques | Asked By Tom Schmidt | Sep 19 14
4 Answers

Plastic or smart vapor barrier in zone 6?

My builder is planning on using a normal 6 mil vapor barrier on my new build ...the wall structure is R-22 fiberglass with 5 inches of EPS foam on the outside ....the building inspector says that is code ...

In General questions | Asked By bob holodinsky | Oct 18 14
2 Answers

Rated output for electric radiant ceilings?

I've been searching the web for a rule of thumb to calculate the rated output for a 40 year old electric radiant ceiling system. Must be some rule of thumb like 10 btu per suare foot......but I can't find it.
Thanks

In Mechanicals | Asked By Walter Gayeski | Oct 17 14
2 Answers

Catherdral ceiling insulation

We have a cape cod and are having a new roof installed. The stairs leading up to the second story, the cathedral part, with two rafter bays of 2x6's had no insulation in them. The roofers pulled the roofing deck and put in some batt insulation, (R30 with a plastic wrapping that had holes) and some attic cat they put in by hand. They also put in plastic baffles between the decking and the insulation. Unfortunately at the bottom of the rafters it is completely blocked off. So there will be no air being pulled in from the soffets. There isn't a way to get them open.

In General questions | Asked By HD S | Oct 16 14
2 Answers

Best integrated system for water heating and radiant floor heating?

I'm looking to remodel my home and install radiant floor heating system. Can anyone provide any information on good heat sources (boiler, water heater, etc) and system arrangement (direct, indirect, closed loop, etc). Is it okay to combine DHW with radiant heat or is there some over arching reason why they should be kept separately?

Home details: Just south of San Francisco, 2500 sqft, two stores, 5 zones, Warmboard S floor board, mostly covered with hardwood flooring.

In Mechanicals | Asked By Dmitriy Khazansky | Oct 17 14
10 Answers

Radon

Question for you:
My basement was tested at 5.1 and then 6.5, short term tests. unoccupied space.
The living room first floor was at 2.7.

If still interested in radon mitigation, how can this be done at the slab if this is an 80yr old home that does not have any stone under the slab in the basement? The floor is on soil?

Thanks,

Dave

In GBA Pro help | Asked By Dave Mac | Oct 13 14
3 Answers

Experience with Rinnai vent-free convectors?

Anyone used or have experience with Rinnai Vent-Free Convectors?

I'm a little baffled by this product. No ducts, no vents, nearly 100% efficiency. Relatively low cost, relatively low total load. Am I missing something here? It seems like the low load crowd would be all over these, as a backup heating up for high efficiency minis if not as a main line unit.

http://www.rinnai.us/vent-free/products

In Mechanicals | Asked By Keith H | Oct 16 14
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