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0 Answers

Remote cabin exterior wall design.

Questions on remote cabin exterior wall design. I am building a small cabin, off grid in a remote location - Yukon Canada (cold dry climate). Not for full time habitation, but I suppose that could change in my future or with a with a different owner. Wood heat only, small solar to run LED lights, 12v stereo, no running water. Dimensions 16' x 24' (2 stories). I would like to minimize the exterior wall thickness as the interior space is not especially large to begin with. Cost and ease of construction are major planning considerations.

Asked By J. Bishop | Mar 4 15
12 Answers

Adding wall R-value in a historic retrofit

What options are available for adding r-value to a wall if we can't remove the exterior siding? I see three options...
1) dense pack cellulose in the existing 4" wall cavities (~R 14-16)
2) Closed cell spray foam in existing 4" cavity (~R 26-28)
3) Add a double interior wall filled with 7.5" of dense pack cellulose (~R 26-28)

Asked By alok khuntia | Feb 28 15
5 Answers

What is a correct way of fastening two layers of 2" rigid insulation to the exterior of a 2x6 wall?

I would like to know the correct way to fasten two layers of rigid foam insulation where the total thickness is 4". I am concerned that when hanging this thickness of foam it will be difficult to be sure that the siding application is secure. We will be using HardiePlank horizontal lap siding. This is a form of cement board and heavy on it's own. Any advice.
Thanks

Asked By william dempsey | Feb 26 15
4 Answers

Insulation question

I have an apartment want to add insulation from the exterior.
It is a block building 1950's vintage. Walls in the inside are stripped with 3/4 furring strip. Insulated with 3/4" fiberglass with vapor barrier on inside. Finished inside with plastered walls.
I am thinking of adding foam sheet insulation to the outside of the building. I do not want to trap in moisture and cause mold problems. .
What is the proper way to do this. I do my own work. If anyone can guide me in the right direction I would appreciate it.

Thank You,

Asked By Charles Craig | Feb 24 15
12 Answers

"Pretty good house" window choices

Hi, we are in the design stage of a high efficiency retrofit and addition to an 1888 Victorian house in the Chicago suburbs. Our architect and his preferred builder are leading many of the Passive house projects in the area and are very interested in getting our project to approach those standards. Although i think it would be very cool as well, i am finding that the technical approaches and costs simply don't justify the benefits. In doing my own research, i am leaning towards designing for "pretty good" near net-zero instead of near-passive.

Asked By alok khuntia | Feb 27 15
2 Answers

How to properly vent a modfied gambrel roof?

Hi,
My family and I purchased a 2 story modified Gambrel style home 5 years ago. By modified, I mean that the vertical roof sides go all the way to the foundation. So we have sloped interior walls upstairs and downstairs.

Asked By Charlie Baxley | Feb 23 15
4 Answers

PERSIST in South Florida?

this question is for those familiar with PERSIST style building techniques.
I am considering building a home using PERSIST construction instead of CBS construction in south Florida.
(1) Does anyone know if Grace IWS would effectively stop termites?
(2) would exterior stucco be sufficient in protecting XPS from deterioration and infestation?

Asked By John B | Feb 26 15
4 Answers

Passive Radon Mitigation using Solar/Wind Turbine Fan

Here's my dilemma: New home less than 5 years old with passive radon mitigation system that runs up through the house exterior walls. Ceiling is vaulted so there is no attic or way to install a radon fan up there. Got quote to reduce radon and contractor said to cap off the existing pipe and install a new pipe that runs up along the outside wall with an attached fan, essentially abandoning the existing passive system.

Asked By Robert McDonald | Feb 26 15
9 Answers

More berm or more insulation?

Currently I am finishing up a design of a house that I want to build this spring. The way the house is designed necessitates it being bermed up with earth on the north side a couple of feet more than the south side of the house. So I have the option to either add more concrete to the north side, berming it up an additional two feet ( to make a 4ft berm) or just building my stud walls and insulating with dense pack or spray on cellulose (I haven't decided yet which).

Asked By Jeremy DuCheny | Feb 25 15
4 Answers

What's the best way to address insufficient foam R-value outside the vapor barrier in Zone 5?

We're in new construction now, and had to put the brakes on due to moisture in the wall assembly. Our wall design meets code for Zone 5 (Illinois), but we want to make sure we never have a problem with mold.

We're using Ox Engineered Products Structural Insulated Sheathing (SIS) 1" polyiso R-5.5 and 2 x 4 stud cavities filled with un-faced mineral wool, Roxul R-15. The Ox SIS (formerly Dow) has a perm rating of 0.3, so its use requires drying to the interior. It is meticulously taped and sealed, so it is also our air barrier. The Roxul is very vapor-open (roughly 30 perms).

Asked By Dave Brooks | Feb 25 15
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