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16 Answers

I found that patents exist for products that would use the outgoing heat from a dryer to preheat the incoming air, but I haven't found any thing forsale. I'm not going to get away from using my dryer in the winter, but I'd like to do it as efficiently as possibly. Taking warm air from the laundry room, heating it, and then sending it outside, only to have make up air come from the cold outside seems horribly inefficient. My house is much too humid during the winter to use a dryer diverter and the smell is terrible, so that's not going to work.

Asked By Calum Wilde | Jul 30 14
1 Answer

We are meeting a lot of resistance from local concrete contractors & structural engineers when we tell them that we want a capillary break between the footing and the foundation wall. Are there any documented cases of this capillary action being a source of moisture/ mold / finish material problems? Are there any scientific studies that compare the moisture levels in foundations walls with and without a capillary break? The capillary break makes sense to me intuitively, but nobody wants to pay for it or change their ways unless we can show them proof that it is necessary.

Asked By Eric Stear | Jul 31 14
2 Answers

I am a siding installer and I would like to know if I can get paid for my scrap siding.

Asked By Bradley Wheeler | Jul 31 14
11 Answers

Your details show a caplillary break between the footing and foundation walls. What is it? Is it continuous?

Asked By Arthur Ratner, AIA | Jun 23 09
Answers

Hello all,

I am working with an HVAC contractor to design and install a multisplit system for our 1950s ranch renovation. As an FYI, we've done a substantial amount of upgrades to improve the tightness and insulation of the home although at 60 years old the house still isn't perfect. I'm now hoping to replace our aging ducted air handler with a new ductless system. Motivation to go ductless is driven by many factors that I won't get into in this post (both efficiency and a more practical issue of headroom in our finished basement).

Asked By Brian Gray | Jul 31 14
2 Answers

Climate Zone 6B

Asked By JMS Build | Jul 30 14
1 Answer

Many building science resources recommend installing a capillary break over the footing (between the footing and foundation wall). Is there a reason this is preferable to installing a vapor barrier (i.e. 6 mil polyethylene) under the footing, up the inside face of the footing, and overlapping with the under-slab vapor barrier?

I'm assuming the foundation wall waterproofing extends all the way down the exterior face of the footing. I'm in Cincinnati, OH, and my question applies to finished basements, unfinished basements, and conditioned crawlspaces.

Asked By Eric Stear | Jul 31 14
20 Answers

Hi,

We are building a duplex in Yellowknife, Canada - climate zone 8 (design temp minus 45 - same as Fairbanks).

Our winters are long and dark so some sort of (external) insulated window shutter is a huge energy saving opportunity. Our walls are going to R50, while triple pane windows get about R4.

I'm thinking of using 2-3 inches of Roxul board sandwiched between wood. That could give up to R12.

Asked By Andrew Robinson | Jun 10 14
8 Answers

Looking for an answer before I start this project. I live in northern MN. I had my attic spray foamed 4" behind knee walls, 3" in the living space. This is a 1 1/2 story with a non-vented roof. I want to know if its O.K. to use foil faced 1" rigid sheets to cover studs [Editor's note: I think David means "rafters"], with the foil facing down between the knee walls. I did plan on filling all voids and foil taping the joints. Then 1/2" sheetrock over the foam. Just want to make sure this isn't considered a double vapor barrier, and if this would be considered good construction.

Asked By david chinn | Jul 27 14
1 Answer

Hello everybody.

I am currently designing a new single family vacation home in southern New Jersey on the beach. The project is going for LEED for Homes and Energy Star certifications. My main wall section from inside-out calls for 1/2" gypsum, 2x6 stud wall w/ batt insulation, 1/2 plywood, 1-1/2" rigid foam, WRB, 1x4 furring/air space, fiber cement siding. Air sealing details are similar to those offered in the GBA detail library. As a summer vacation home the main usage would be during the cooling season.

Asked By kevin field | Jul 30 14
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