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8 Answers

SIP rot and remedy

I have had to recently address a SIP panel issue, installed 7 years ago, on a timber frame building. The issue being, that the spline joiners between the panels, seem to have had a "chimney " effect resulting in moisture/heat travelling to the peak area. Combined with a butyl membrane encapusulating the entire exterior surface, the SIP's had zero permeability for the panels to breathe. The equation ended up with roof rot of the exterior SIP's OSB panel, and rot of the joining headers.

In GBA Pro help | Asked By Mark | Dec 2 15
1 Answer

Cathedral ceiling insulation

Zone 3 needs R-38.
2x8 truss, 12/12 pitch.
Metal roof, 16 square roof.

Would you prefer:
7 inches open-cell foam, then 2.5 inches on polyiso nailbase on roof, or
BIBS (R-30) touching roof deck and 2 inches polyiso nailbase on top of roof deck, or
something else?

Is one option way better than another or way cheaper but as effective?
Or is there a better option?
...than If you had the option of using a vented nailbase instead of nailbase and a fascia vent for some venting under the metal. Would you, at a cost of about $2,500 extra?

In Energy efficiency and durability | Asked By Quinton | Dec 3 15
6 Answers

Saving beetle-damaged reclaimed framing lumber

Is there a practical way to make safe beetle damaged framing lumber?

In this case it's 1930's era old growth douglas fir 2x4 rafters, which were removed then stored outdoors. Pretty much all of them have beetle exit (or entry) holes (see representative picture). The wood is plenty strong, but clearly the beetles can (and did) spread.

In theory killing methods include: heat/kiln cooking, chemical saturation, microwave energy like that used for termites, freezing. But in practice, in the San Francisco Bay Area, is this wood compost or fixable? What's the green thing to do?

In General questions | Asked By Bryce | Dec 1 15
5 Answers

Help identifying off-gassing from spray foam insulation

Our Demilec Agribalance open cell polyurethane spray foam insulation has been off-gassing a smell since it was applied 7 months ago. Before I move my family back into the house I'd like to know what's coming from the foam, especially since Demilec lists a safe exposure level for their amine catalyst (a likely cause of the smell) at only 0.05ppm.

In Green products and materials | Asked By Allen Poole | Dec 3 15
13 Answers

Freedom Pet Pass - energy efficient pet doors?

Our dog has had one too many accidents on our living room carpet while we're away at work. My other half tells me either to a) install a dog door so our pooch can go outside to do his business...or b) bring him to doggie daycare at ~$20/day. While I don't like the idea of a dog door (every one I've seen leaks like crazy), $20/day would quickly cover the cost of a PV system I want to install.

In Energy efficiency and durability | Asked By Robert Hallenbeck | Dec 1 15
13 Answers

Unintended vapor barrier using oil-based stain on wood?

I need to stain some new bookcases (floor-to-ceiling) located on exterior walls. I want to use oil-based stain but am concerned that may act as a vapor barrier. The literature and other posts discuss the need to avoid vinyl wall paper or oil based paint on the wall in my climate zone (2B). Does oil-based stain (probably with varnish top coat) on the book case fall into this same category? The wall-to-book case surface of the book case is unpainted.

In General questions | Asked By John Walls | Nov 16 15
16 Answers

Ideal load for a multispeed inverter-driven GSHP?

In a planned "Pretty Good House" in Mixed Humid, Northern Climate Zone 4, I intend to use a 45 EER Ground Source Heat Pump with 3 inverters (loop pump, compressor, and fan) with a Cooling Capacity range from 9,000 - 24,000 Btu. I wish to have the lowest Peak Cooling Load, that utilizes the equipment most efficiently, while providing dehumidification and keeps short cycling to a minimum. Approximately what sould that theoretical Peak Cooling load be ?

In Mechanicals | Asked By Ted | Nov 19 15
1 Answer

Spray insulation in pole barn

I have an non-insulated pole barn with vinyl over cedar siding exterior. I keep inventory for my business there and several dogs. I am considering spray insulation Square footage is 1600-1800 sq ft, with three aluminium overhead garage doors. I have a quote for open cell insulation for the walls and a separate quote for the roof. I live in the Raleigh, NC, area. Winters can get cold enough to freeze water in dog bowls.

1) Is open cell the best way to go?
2) Is spray foam insulation on the garage doors valuable, or will the extra weight be a problem for the track system?

In General questions | Asked By John Paparone | Dec 2 15
4 Answers

How do I insulate an existing cathedral ceiling in Maine?

The ceiling I want to insulate was built with 6 x 12 rafters 4 feet on center. Sheathing is 1 1/4 thick tongue and groove pine then asphalt shingles. So the boards are exposed. Also no vents at all.

In Energy efficiency and durability | Asked By Kevin | Dec 2 15
5 Answers

Insulating unvented roof assemblies

I had read the article here.... http://www.finehomebuilding.com/how-to/departments/energy-smart-details/...

and since 1 and 2 require foam above the roof sheathing which I can't do without redoing the roof which is high expense it leaves 3 and 4. The comment seems to be under the "how much insulation" that "code requires the [closed cell] foam layer to meet specific minimum R-values" in the table. I assume the closed cell based on the air-permeable comment.

In Green building techniques | Asked By Michael | Dec 1 15
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