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1 Answer

Porch / deck over conditioned space — insulation question

Ok and thanks in advance. I have a small deck/porch located directly over a bedroom on the first floor. The area is approx. 5'x12' and it was uninsulated since the very early 1900's when the addition was added. Here's a little diagram. I'm wondering:

In Energy efficiency and durability | Asked By Geoffrey Cook | Oct 7 13
2 Answers

Low slope attic/cathedral ceiling ventilation in climate zone 3c

I have been remodeling my 90 year old bungalow in Oakland, Ca. It has never had ventilation in the attic and shows no signs of problems. I have converted about a quarter of the roof to a cathedral ceiling with 4" of polyiso foil faced insulation carefully foamed into the rafter bays and with a 1 1/2" space above the insulation. in the rest of the attic, I added a foot of blown in fiberglass after foaming/caulking any gaps I could find and reach. We are getting ready to redo the composition shingle roof but none of the ridge vents I have found are recommended for my 2 1/2 / 12 roof slope.

In General questions | Asked By Andy Kahn | Oct 2 13
2 Answers

What is the best ventilation scenario for my very small, tight house?

(Climate zone 4A - Charleston, WV) I built a small (12' x 24' main level w/ loft) guesthouse in my back yard. I am fairly new to building and decided to experiment with building it as tight as possible. I caulked all the stud bays, foamed around all window and door opening, etc. I don't have specific numbers but with all the windows closed there is a definite suction when the door is opened or closed. (Please excuse my vagueness, I have not done a blower door test). For simplicities sake I had planned on doing an exhaust-only ventilation system based around the bathroom exhaust fan.

In Energy efficiency and durability | Asked By d c | Oct 5 13
1 Answer

What is the correct detail for apply stone to a poured foundation?

Do I need an air space or particular flashing? I looked in the construction detail section but didn't see what I was looking for.

I have a poured foundation. We intend to install real stone on the above ground portions. It will be field stone ashlar between four and six inches thick. What the best practice of this type of install?

In Green building techniques | Asked By Steven Knapp | Oct 5 13
6 Answers

ERV or HRV? Need help for musty cabin

I have a 1,600 sq. ft. log cabin located in New York (Catskill region) built in 1972. The cabin is used part-time, mostly weekends -- sometimes a week at a time.

The cabin always has a musty smell. I need to choose the best way to improve the air quality. This home can be shut for weeks at a time. In the summer I run a dehumidifier in the basement 24/7 at 65%.

In Mechanicals | Asked By evan feldman | Jan 4 12
2 Answers

Best loose fill insulation for concrete block?

The frost wall of our addition is concrete block. What is the best loose fill insulation for the hollow cores? Vermiculite? Perlite? EPS beads? (I understand they are made with the waste of EPS board, so this mitigates the environmental impact? Other ideas?


In Green products and materials | Asked By Edward Krause | Oct 4 13
3 Answers

Cedar Impressions over 2 inches of rigid foam?

Has anyone installed Cedar Impressions perfection shingles over 2" of rigid foam? Certainteed says that you should only apply directly over 1" of foam, but the client is looking for 2 inches and furring everything out would add significant cost and complexity to the project.

With the client's consent, I'm considering applying the siding directly over the foam and using longer nails to ensure appropriate penetration into the studs. I realize the corners may take some thought to hit the studs, but can anyone think of something else that I am missing? Has anyone done this before?

In Green building techniques | Asked By Orrin Levine | Oct 3 13
3 Answers

Should I use Cor-A-Vent?

I'm using wood siding and rainscreen vent over closed cell spray foam/OSB/felt/3/4" furring. Cor-A-Vent seems quick and easy but expensive. I haven't seen any similar alternatives. Insect screen alone seems labor intensive and not very durable.

In Green building techniques | Asked By Roy Brohaugh | Oct 3 13
4 Answers

Is there any drawback to leaving 6-inch-wide white pine covering a catheral ceiling unfinished?

For aesthetic reasons I am using 6" wide 3/4 " thick, white pine boards to cover my catherdral ceiling. The unvented cathedral ceiling has 4 " of closed closed cell foam, followed by 6" of open cell foam 0.8lbs/cuft, followed by 1 1/2' XPS over the rafter cavity for reduction of thermal bridging. The 5/8" plywood roof deck is covered with #30 felt paper and Certain Teed Energy Star certified asphalt shingles of high reflectance.

In General questions | Asked By JOSEPH POLAND | Oct 3 13
10 Answers

Rigid exterior insulation over existing OSB siding?

Hi Everyone,

I live in Redmond, Oregon Zone 5B and I am working on a 24W x 36L shop that I am trying to shoot Closed Cell spray foam into (7" in rafters and 4.5" in walls) hopefully before winter really hits. I read a lot of the articles on this site so I feel somewhat well informed but I still have a few questions as to my specific project/dilemma.

In Building Code Questions | Asked By Max Anthony | Oct 2 13
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