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3 Answers

A builder I am doing energy consulting with has used tech shield roofing material on the exterior walls. The foil is manufacturer perforated for moisture. Is this a good or durable application for this sheathing? Will it effect the wall system?

In Green products and materials | Asked By Bruce Glanville | Jan 12 12
1 Answer

I've got some plugs in the siding now that indicates blown insulation was used. I don't know if cellulose or fiberglass was used, but my walls are COLD. I have already talked to my siding contractor about 4 inches of foam board and a layer of house wrap. Would it be overkill to add additional insulation inside the walls either on top of the existing insulation or by removing and replacing it? Spray foam insulation is all the rage right now, but the cost is substantially higher than cellulose or fiberglass.

In General questions | Asked By Jason Schaffer | Jan 13 12
14 Answers

A friend of mine drylined his interior walls about 3 years ago. The wall construction is of concrete hollow block construction, rendered on the exterior with plastercoat to the interior face. Bear in mind this is a wet, windy, and cold climate.

This wall was subsequently insulated to the interior using 50mm (2") (Possibly EPS boards, but he was not sure whether EPS or fiberglass when I asked) insulation with 1 layer plasterboard over, then plaster skim coat to finish.

In Energy efficiency and durability | Asked By Tim O Brien | Jan 11 12
23 Answers

We are planning to build a 1250 sq. foot A-frame. The problem is the roof as the inspector is requiring R-49. We know we want it to be well insulated. But due to the roof actually being the walls also...insulating space is an issue. We have already decided to to 2x 12 rafters with 2 inch ridgid on the outside for the roof. Walls are to be 2x4 with again 2 inch ridgid foam on the outside. Has anyone used Protex? Also does anyone one know where to get reclaimed 2" inch foam in this area?

In General questions | Asked By maureen mcginnis | Dec 25 11
5 Answers

A supplier here in Ireland advocates the use of timber-framed walls using timber studs and insulation between 2 layers of plywood WITHOUT using any tapes or other adhesives to air seal the junctions..

The large prefabricated frames consist of plywood as the air barrier and silicone is used as the air gasket / adhesive squeezed between studs and plywood.

I have misgivings but is silicone used this way a durable and effective alternative to traditional fixing methods with tape at plywood junctions?

In Energy efficiency and durability | Asked By Tim O Brien | Jan 11 12
2 Answers

I read your article on your website "Calculating Minimum Thickness of Rigid Foam Sheating" and viewed the rigid foam installation video on YouTube with David Joyce. Thank you for having a great website and videos with lots of information.

In Energy efficiency and durability | Asked By Owen Nelsen | Jan 12 12
12 Answers


I have a tight house (2.0ach50p) and want to install a heat pump water heater in the heated basement. I have no back draft appliances and the house is all electric with a fully ducted HRV system. I occasionally run the range top fan on low and a bath fan for 15 minutes or less (timer switch).

In Energy efficiency and durability | Asked By Frank O | Jan 10 12
3 Answers

This Zone 5, coastal roof is leaking and going to be replaced via a low-interest, deferred HUD loan. (See photos). I had dreams of a Deep Energy Retrofit, but even with generous incentives from the electric utility, the expense is too great for the loan recipient, and a VERY incremental approach is required.

In Energy efficiency and durability | Asked By John Rockwell | Jan 11 12
2 Answers

I am replacing the water table and belly band on my 1903 house that had the foundation replaced.

The wall constructions is studs, turned either short or long side out, and then board and baton style sheathing, and then lap siding. The board and baton form a sort of drainage plane behind the siding. However, there's no building paper vapor or air barrier over the sheathing, and the boards seem like there are plenty of air leaks between them. The walls have cellulose insulation, and the siding is covered with asbestos cement shingles, which I hope to remove some day.

The dilemma is this:

In Energy efficiency and durability | Asked By Adam Liberman | Jan 11 12
5 Answers

A customer of mine is being told by his builder that he can't switch to roof deck spray foam and an unvented attic because that will change (reduce) the resistance to wind loads compared to the as-designed house with soffit and ridge vents. We are in a 130 mph wind zone.

In Energy efficiency and durability | Asked By Kevin Veach | Jan 10 12
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