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3 Answers

Capillary break

I am getting ready to insulate my basement in preparation for future finishing into living space. My home is located in NE Pennsylvania and was built in 1859 and sits on a field stone foundation. The foundation overall is in very good condition. It is is need of re pointing in some areas but over all in good condition. The basement is damp on two of the walls and during periods of heavy rain weeps water slowly. I have already installed a french drain to daylight around the two walls that periodically weep and are damp on the lower half for much of the year.

In General questions | Asked By Ben Hardy | Sep 15 16
12 Answers

Foam-free attic insulation?

Hi, I understand spray foam (or possibly rigid foam) is strictly recommended when insulating between the rafters of the attic Both prevent wintertime condensation at the sheathing and eventually rot and roof failure. However, I am failing to see what would be wrong with the following foam free approach to insulating my attic in climate one 4A . Leave 2 inch ventilation gap between underside of the rafter and then install water resistant barrier (but highly vapor open) such as Solitex Mento 1000.

In General questions | Asked By Matthias Paustian | Sep 14 16
2 Answers

What kind of mini-split, if any, would you recommend to heat, cool, and dehumidify an outdoor metal storage container?

We have an outdoor metal container (45" long x 8" wide x 8" high) in which we would like to store mostly photo slides, and fine art painted on wood. We would like to heat, cool, and dehumidify it as affordably as possible to reach about 50% humidity and 60 to 85 degrees temperature in Beacon, New York where it gets below freezing in winter and above ninety in summer. The container will be hooked up to the electric grid so we will have electricity.

In Energy efficiency and durability | Asked By Valerie Aubry | Sep 16 16
18 Answers

HRV duct set up

I am getting ready to install my HRV. I have been contemplating exhaust in the two bathrooms, three bedrooms, and kitchen area, with only one supply duct in the great room near my mini-split. 1300 square feet, one level, 3 1/2" exterior foam, 6" fiberglass batts, unvented sealed crawl space. The design person at the HRV store is said I should have supply to all bedrooms and just exhaust the bathrooms/kitchen. Climate Zone 7, so I am a little concerned about supplying all that fresh air to the bedrooms in the dead of winter.

In NAHB Class Discussion | Asked By Steve Vigoren | Sep 6 16
16 Answers

Source of ammonia odor in a home (indoor air quality)

We have built a home which is well air sealed and have registered for LEED status, which will be finalized later, when the alternative energy projects and landscaping are complete.

In Green products and materials | Asked By Andrew Katz | Sep 10 16
4 Answers

Unrealistic R-value claims are alive and well

OK, someone please explain to me how they claim R-64 while only using 8" of EPS which is around R-32? They claim R-8 per inch of insulation on the wall or roof.




In Green products and materials | Asked By Peter L | Sep 15 16
2 Answers

Rock wool insulation?

For my partially sub grade bedroom space, I am averse to spray foam insulation because of the inconclusive endorsements I get when I ask if it off-gasses long term, even if correctly applied. No one from your organization or elsewhere seems to offer definitive endorsement.

In Energy efficiency and durability | Asked By Chris Campbell | Sep 15 16
16 Answers

Who’s up for another house plan review?

Last time someone posted a house design, people seemed to enjoy critiquing it. If you enjoy doing that, here is another chance. If not, please ignore this thread.

I created this house plan with my in-laws in mind. We are trying to convince them to move closer to us near Flint, Michigan. If we can find a nice lakefront lot to build on and a good design, we might have a chance. They are retired. Stairs are not currently a problem for them, but the house is designed so that they wouldn't need to go to the second floor.

In Plans Review | Asked By Reid Baldwin | Sep 11 16
8 Answers

Roof assemblies - minimum insulation value

In my state our code specifies a ceiling R-Value of 38 (climate zone 5A) - but in the 2012 IRC it requires R-Value of 49. For an unvented ceiling with no attic space, solid continuous insulation, will R-40 be sufficient?

In Green building techniques | Asked By John P. | Sep 15 16
1 Answer

Unlined masonry chimney - replace with metal?

This is part of the 1910 attic insulation project describe in:

As with any renovation, expect the unexpected.

There is a brick chimney that runs through the center of this house, rectangular with 2 chambers:
Main column: 20 x 28
Just below the roof: 28 ½ x 37 ½
Above the roof: 31 x 38

In Energy efficiency and durability | Asked By TIM LANGE | Sep 15 16
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