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4 Answers

Building a 12x15 multipurpose shed, most of the time just storing stuff unattended in Central Texas heat (and very rare freeze). Framed brick construction (light colored brick) with white metal roof, one window and french doors. Roof on top of radiant barrier. Attempting to beat the heat (9 mo/year and sometimes beyond 110 degrees), and condensation after fast temperature drops (sometimes >10 degrees/hour). No use of grid power (eventual plan is small solar system for lighting, fan, and radio). 3 months of the year there can be cold weather also, occasionally freezing.

In Energy efficiency and durability | Asked By Charles Peterson | May 18 11
6 Answers


I am building a 600 sq foot cabin in US climate zone 5 with 2 by 6 wall construction. I have gotten a lot of great information from your web site and, as a result, the wall system from the outside in is 1.5 inches of XPS rigid foam insulation, housewrap, plywood. I am trying to decide what kind of insulation to use in the wall cavity.

In Energy efficiency and durability | Asked By Ron Baker | Jan 6 12
5 Answers

I guess I'm asking a Building Science question here, but in a Northern Climate (e.g., 6A), What does an interior vapor retarder actually do, especially if the air barrier is at the sheathing layer for a typical 2x6 wall with fibrous insulation? I can understand an interior temperature of 68% with a relative humidity level of 35% (and the dew point that must be kept higher than any condensing surface, which seem to the real parameter of interest in all of these discussions), and I can understand the temperature gradient (and its associated "humidity" gradient increase with dew point change).

In General questions | Asked By Bob Manninen | Jan 6 12
22 Answers

Hi All,

I have house just north of Boston, in Zone 5. It is a contemporary home built in 1983 with nearly 100% cathedral ceilings. I have an active leak on one of the roof sections, and as such will be replacing the roof very shortly. The roof section is 6/12 pitch 22 feet wide and 28 feet high with two layers of asphalt shingles.

I would like to address some of the shortcomings of the existing roof system which are:

In General questions | Asked By Bernie Simon | Dec 31 11
3 Answers

I am using the GBA wall section detail #2-00004. I have been looking online for the insect screen described in the detail. I envision it as something like a soft mesh that is 3/4 thick. Is there anything out there that is not too expensive? If so, who is making it?

In Green products and materials | Asked By Beth Robinson | Jan 6 12
5 Answers

My wife & I are remodeling a house to accomodate a 133 inch long dining table when fully expanded. Most of the time the table is closed to a 60 inch diameter. We will install a south facing window approx. 7 ft. long x 4 ft. high. Except for when the table is fully expanded (1% of the time), we could have a passive solar heat sink inside the room near the window, but need to move it to accommodate the table when fully expanded. Have been thinking of something water filled. We could install a faucet & drain in the room. A movable sink would also allow it to be unused during the summer.

In PassivHaus | Asked By Robert McDonald | May 24 09
6 Answers

Patrick McCombe, an editor at Fine Homebuilding, e-mailed me this link to a YouTube video reporting on how one British builder handles deadbeat clients:

In General questions | Asked By Martin Holladay | Jan 5 12
15 Answers

Does this practice (flash and batt) work with single wall construction where the foam is sprayed against housewrap?

Some builders in the KC metro area use single wall construction. To meet efficiency expectations they are wrapping the home, spraying 1/2" to 1" closed cell foam and filling the cavity with batt insulation. Does this cause issues with moisture migration?

In Energy efficiency and durability | Asked By Bruce Chyka | Jan 4 12
6 Answers


We have just completed construction of an addition on our home in zone 5A. The addition has a walk out basement that does not have a heat or a/c duct located in the space. The walls were built with concrete block to above grade (floor to about 38") and then the rest is a 2x6 studded wall (about 58") The wall construction as of now is as follows from outside in. Brick veneer - 2" vent space - OSB sheathing attached to 2x6 stud wall OSB is wrapped with Tyvek on the exterior.

In Energy efficiency and durability | Asked By Martin Miller | Jan 5 12
3 Answers

I have an energy makeover project for a client with an older log home. Beyond the usual infiltration issues we need to repair/upgrade the roof.

Current: asphalt shingle, tar paper, OSB in fair shape -- some rot and rodent damage, but not past fixing.

One plan is to strip back to OSB, repair as needed, add tar paper, 4" SIP Nail board, More tar and paper and a standing-seam metal roof ready for PV.

Thoughts? Ideas? Criticisms?


In Green building techniques | Asked By Bruce Glanville | Jan 4 12
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