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1 Answer

Garage insulation

I am about to insulate a detached garage in climate zone 7. The homeowner wants it to be insulated on the main level as well as the attic level (roof plane). The ground level has 6" walls and 8" ceiling joists. The attic level has 4" walls and 6" rafters. I am wondering if I can insulate the walls and ceiling joists with batts and then put a 2" layer of foam on the underside of the ceiling joists before finishing the interior. In the attic, I will run a continuous 1" air space soffit to peak and run a ridge vent.

In Energy efficiency and durability | Asked By ben g | Feb 24 14
1 Answer

Matterhorn roofing


Click on a link at GBA for Matterhorn roofing. They claim 25% reduction in energy costs. Dont see how this can be true.

In General questions | Asked By Robert Hronek | Feb 24 14
5 Answers

My intake duct for the HRV seems to be collecting moisture as the insulation is wet

My intake duct for the HRV seems to be collecting moisture as the insulation is wet. There is not enough snow close to the intake so I don't think this is the issue. What else could be causing the issue?

We have been the house for five years and have never seen this problem. We use the HRV mainly in the winter.

In Energy efficiency and durability | Asked By Jefff Bean | Feb 22 14
11 Answers

Log home insulation retrofit

I'm exploring strategies for insulating an existing log home. External insulation makes the most sense to me. What are thoughts and comments about this assembly: 2x4 stud wall with closed cell spray foam covered with r-sheathing? The sheathing is needed because I think the budget will require vinyl siding. I'm not sure about air barrier and a drainage plane tho. Any comments or suggestions would be appreciated. Also thought about a nail-base sip, but I'm concerned about how to attach it, and possible thermal bridging if long lag screws were used....

In Energy efficiency and durability | Asked By Sandra Heiser | Feb 14 14
1 Answer

Sizing timber frame roof purlins

For those of you that live in a moderate snowy area such as Pennsylvania or New York and have a Timber Frame roof system of bents and purlins with t&g on top of purlins. Question is with bents on 16' centers what size purlins do you have? I imagine to satisfy the code it would be considered rafters with ceiling attached which would fall under the 240 deflection rule. For purlins on 48" centers, 15' length at 30psf (1800 lbs) a 5X7 would have .799 deflection, a bit above the allowable .75. This is telling me it would require a 6X8. Make sense?

In General questions | Asked By John H. Stehman | Feb 23 14
16 Answers

Insulated slab on grade design

I have several questions about the Insulated slab on grade design. I have seen it done several ways on the internet and really need some advice. A little background on the project.

In Green building techniques | Asked By Thomas Perkins | Feb 17 14
2 Answers

I am interested in the Condensation Resistance values that I see on different windows

I see that the NFRC has these calculated for all different windows.

Does anyone know how to correlate the CR value with actual temperature and humidity levels in the house. Any calculator out there somewhere?

i.e. what CR value is needed to prevent most condensation on a window when the outside temperature is -10 degrees and the inside temperature is 70 degrees and the indoor RH is 25%?


In Energy efficiency and durability | Asked By Marc Sloot | Feb 22 14
11 Answers

Who are your favorite online suppliers?

Hi all,
I'm sniffing out a story for Fine Homebuilding on how progressive builders are acquiring their progressive materials for remodeling and new construction.

There are lots of online suppliers for building materials these days: Conservation Technology, Energy Federation, Energy Conscious, Small Planet Workshop, GreenDepot, even Amazon.

In General questions | Asked By Justin Fink | Jan 8 14
2 Answers

Does an AC compressor located in full sun work harder than one located in the shade?

Our AC compressor is located on the south side of our Florida home and it seems to me that if it were shielded in some way it would not have to work as hard - is this correct?

In Energy efficiency and durability | Asked By Chuck Mucciolo | Feb 22 14
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