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3 Answers

What fireblocking is required in double stud walls filled with dense pack cellulose?

Single floor over basement (unheated) residential, about 2400 sq ft. gable roof 18" cellulose ceiling insulation. Fiberboard sheathing XPS rain screen thin brick exterior. I would like to use OSB on the outer face of the inner wall. I'm hoping this will eliminate any required vertical fire blocking within the wall. plan on "capping" the top of the 2 wall assembly with OSB, can it be 7/16" or must it be 3/4? Wall insulation is dense pack cellulose.

In Building Code Questions | Asked By Jerry Liebler | May 30 12
5 Answers

Rigid foam without furring strips under dry wall

I'd like to add 1" rigid foam (XPS) over my rafters on a cape cod (above knee wall) cathedral ceiling w/o the hassle of furring strips as some of FH Bldng articles show. I'll finish that w/1/2 inch drywall. I have R 21 fiberglass paper faced batts in that cathedral ceiling and plastic baffles for air flow from eaves to ridge, exhausting out side gables as the back side of that top floor has been dormer-ed. Are the furring strips necessary?

In General questions | Asked By Jeffrey Kolsch | May 31 12
8 Answers

I'd like to do a bad attic insulation job - will this work?

I'm only sort of kidding. House is very large, 100 year old brick center hall colonial in historic district in central Virginia. No exterior modifications will be allowed. Venting is by gable vents, around 4 sqft at west end, 8 sqft at east end. No soffit or other vents are present or possible due to historic district regulations (not to mention practicality). Large 3rd floor is built into the slate roof with dormers. Ceiling of 3rd floor is not even close to sealed. Extensive hvac in attic is not sealed or insulated even vaguely correctly.

In Energy efficiency and durability | Asked By Charles F | May 28 12
1 Answer

Paulownia lumber

I was wondering if anybody has any opinion on paulownia being used for exterior trim? I've used it once and it seems really soft, and not that durable. It's great to work with because it's super straight and clear.

In Green products and materials | Asked By christopher jones | May 30 12
2 Answers

Using foam board in the rafter bays to create a hot roof


In Green building techniques | Asked By Olav Ormseth | May 30 12
1 Answer

Air Conditioning

My home is in VA. I have a 1-yr old Carrier Comfort Series 2-Ton Split system AC unit in the first floor of my home. During the last Memorial Day weekend, outside air was about 84 degrees and humid. Inside set temp.was 74 degrees. Why the indoor unit was running non-stop, even though the inside temp. was same as the set temp.? Also, outdoor condenser unit was not running non-stop while the indoor unit was running non-stop.

In General questions | Asked By sisir mukherji | May 30 12
4 Answers

Blue board and plaster

My walls from the outside in;
Vinal siding
2x6 w/ roxul
1 in foil faced polyiso
1/2 blueboard

What should I do for plaster and Paint? I know the rule is latex with outsulation but what about my set up? Do I use latex over plaster? I'm in zone 6.

I was looking at American clay as an alternative. Anyone use it before?

Thanks, Steve

In General questions | Asked By stephen edge | May 29 12
10 Answers

Need help with recycled polyiso insulation in attic

I found a great deal on recycled polyiso boards that were once a roof on a commercial building with EPDM rubber over it. Each board is 4 foot by 4 foot and 4 inches thick.

I am going to use them in a 1830 post-and-beam house. The boards are going to be going in the attic. There is currently no insulation or vapor barrier in there. The house is in upstate NY and sees some seriously cold winters (at least in the past).

In Energy efficiency and durability | Asked By Larry Broderick | Feb 7 12
4 Answers

How do you attach a large amount of insulation to a concrete wall?

The house I am building in zone 5a will have concrete walls (2 story) for high thermal mass. I would like the walls insulated to R-30, but am concerned about how to attach so much insulation. Will 5 inches of polystyrene get me to a R-30 and how will it attach to the walls? Is there a better way to insulate concrete?

In Green building techniques | Asked By Denise Elliott | May 29 12
4 Answers

Worth worrying about heat loss through aluminum door threshold?

I've just replaced a door between the house and unconditioned garage, where the temperature regularly gets up to 110°F in summer (i.e. the garage is basically a greenhouse). I was really focusing on air-sealing so I completely replaced the jambs with exterior door jambs with Q-lon etc.

The bottom of the door I wasn't sure about, and I had an aluminum threshold with a rubber gasket handy so I put that in at the bottom of the door (removing ~3/4 of an inch of door).

In Green building techniques | Asked By James Howison | May 24 12
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