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9 Answers

Vapor Open Wall Assembly - Multifamily Project in Zone 4

I am working on a new apartment project in Frederick, Maryland (Zone 4).
The project consists of several four story wood framed buildings (units only on levels 2-4).

We are interested in building above "code minimum" buildings because we are long term holders, want our structures to last, and think it is the wise thing to do.

I am persuaded by the benefits of placing insulation on the outside of the wall (the "perfect wall" as described by Building Science Corporation).

In Energy efficiency and durability | Asked By Shane Pollin | Dec 13 12
6 Answers

Gable vent

Hi everyone,
Does anyone have any suggestions on designing and building gable vents? other than 'do not design and build a gable vent.'... Thanks!
I am particularly concerned with preventing blowing snow from entering the attic...

In General questions | Asked By erik olofsson | Mar 5 13
4 Answers

I am looking for product information on a structural block called FASS.

Thank you for your responses. I have received the information I needed to formulate my presentation. I have removed this post because I don't want it to negatively effect anyone's perception of products they may use or are using. Thanks again for your input.

In Green products and materials | Asked By Jason Butler | Feb 25 13
8 Answers

We are bulding a new energy-efficient house in western Canada, and are looking into an outdoor wood boiler

Our house has a hydronic heat system, Warmboard subfloors, double exterior walls, R-60 ceiling, etc... We are installing 6 vacuum-tube solar panels, a small electric boiler, but want to use an outdoor wood boiler for the majority of the heating needs during winter.

There are so many options out there and all claim to be the best, most have efficiency ratings in the high 80's. We would like to heat a 500 Gallon + tank then use closed loop systems (passive in the tank) to heat multiple buildings.

Any suggestions?



In Energy efficiency and durability | Asked By Sam Emke | Jan 28 13
20 Answers

Off-grid PV solar for domestic HW

I am planning a small off-grid home and would like to send all surplus energy from the 4.8 kw solar array to a standard electric water heater, probably of 60 or 80 gallon capacity. In effect, it would serve as an additional "battery" once the main battery bank is fully charged. Does anyone have any suggestions or experience on how this might be done in a fairly simple and reliable fashion?

In GBA Pro help | Asked By Peeter Vihvelin | Feb 22 13
16 Answers

rStud insulated 2x6 studs

Although not as effective in eliminating bridging, the rStud 2x6 looks interesting in lieu of external rigid foam over OSB sheathing based on local area construction practices.  Have any technical reports been published as of yet that anyone is aware of regarding results with the product?  Curious as to its strength & performance when compared to traditional 2x6's.  Interesting option to consider with Zip exterior sheathing and good air sealing followed by a blown in insulation such as Manville Spider.

In Green products and materials | Asked By Milan Jurich | Feb 21 12
6 Answers

Shed roof to wall detail

Hi everyone,
Does GBA have a flashing detail for a simple shed roof to wall intersection?
thanks again...

In General questions | Asked By erik olofsson | Mar 4 13
2 Answers

What fasteners to use with Cedar Shingles over 1" IKO Enerfoil?

My wall composition will be: 2x6 studs, 1/2" plywood, 1" IKO Enerfoil (R7), perhaps a breathing mesh? and Cedar Shakes/Shingles. I'm wondering what you folks recommend for a fastener (length/type)?


In General questions | Asked By Evan Macdonald | Mar 5 13
1 Answer

Any ideas or experience with a desuperheater for a ductless minisplit?

Searching the web only gives a few clues. Anybody have practical experience or product/design examples??

Obviously during the summer you can get some free heat and more efficient cooling, at the cost of a small circulation pump running water to heat exchange medium connected with the condenser tubing - my thought is a braised plate seems most logical.

In Mechanicals | Asked By bob coleman | Mar 4 13
2 Answers

Metal roof details.

I am designing a house with a shed roof. There is a 2' 6" overhang to provide solar shading for the windows. I do not like the appearance of a thick SIP roof overhanging so need to provide support for the overhang and fascia/soffit details.

I am trying to keep costs down so trying to keep it simple. I also want to provide ventilation for a rain screen under the metal roof.

In Green building techniques | Asked By Stephen Carlton | Mar 1 13
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