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5 Answers

Metal Ag roof over doubled up foam and ice and water shield

I would like people's opinion as to whether an ag style metal roof (exposed fasteners w/ neoprene washers) would be sufficiently leak proof if installed on strapping over two layers of foam and ice and water shield as detailed on the site here.

In Energy efficiency and durability | Asked By Joel Cahalan | Mar 23 12
2 Answers

Does anyone know about using crushed shells (clam or oyster) for driveways in Washington State?

We are near the shoreline and are required to use a pervious surface material.

In Green products and materials | Asked By Mona Lydon-Rochelle | Mar 24 12
6 Answers

Huber Zip system R-6.6 sheathing and minimum foam R-values

In zone 5 (central OH), the minimum R-value of rigid foam for 2x4 construction is R-5 and R-7.5 for 2x6 construction. What would be the required amount for a 2x4 staggered stud wall on 2x6 plates? Would the Huber Zip R-6 (R-6.6) sheathing be adequate since it would only be in contact with the 2x4 studs staggered to the exterior?

In Energy efficiency and durability | Asked By Milan Jurich | Mar 24 12
1 Answer

Is there value to radiant sheathing on South/West-facing walls in hot climate?

Is there any measurable benefit to installing radiant barrier sheathing panels (7/16" OSB) on vertical walls with a West or South exposure in a Southeastern climate? Of particular concern is the siding material ( 1/2" thick fiber cement shakes) which will seemingly act as an unintended heat storage device, continuing to radiate heat into the wall assembly long after sunset.

In Energy efficiency and durability | Asked By DENNIS MCKENNA | Mar 24 12
7 Answers

HRV and CFM

The energy auditor has just installed an HRV in our house. The blower door test was approximately 2.5. The HRV is installed in the attic with intakes from two of the bathroom fans. The intake is from the outside and after the HRV connects to the forced air return.

Here are my questions specifically regarding the HRV
1) How fast should the HRV run or how much air should it pull when its run continuously?

In Energy efficiency and durability | Asked By Kevin Hilton | Mar 22 12
3 Answers

Stair railings

Does anyone know where i can buy a book that contains math formulas for curved and offset stair railings?

In GBA Pro help | Asked By carl fields | Mar 23 12
7 Answers

Overwhelmed with Insulation Choice in NE Texas with a 3:12 pitch

We purchasing a 3000sf 1950's ranch style house in NE Tx. I really need your advice narrowing down the best insulation for us.

Problem: 3:12 pitch, no insulation and 2 wings of the house only have tiny access hatches that are blocked by ducts, and it needs a new roof in the next couple of years. Opportunity: we can seal up the openings and insulate it any way needed when we replace the roof.

In Energy efficiency and durability | Asked By Tonya McClelland | Mar 22 12
3 Answers

Dirt crawlspace insulation

I live in northern Minnesota. The house I purchased has a large bedroom, half of which is an addition to the house. It gets fairly cold in the room during the winter and I am looking at better insulating it. The addition portion has no slab or foundation under it. It was basically built as a fourseason porch with only footings. There is access underneath from outside with enough space for me to comfortably crawl underneath. It has dirt floor, batt insulation in the floor joists and a flexible/insulated heating tube going to the far end. No other pipes or wires.

In GBA Pro help | Asked By Nathaniel Hughes | Mar 22 12
4 Answers

Polyiso directly over Tyvek stucco wrap vs 1/4" shims between

I am a remodeler, project is my own whole house remodel in North NJ (Morristown - Zone 5). After reviewing your excellent information and blogs the envelope planned is:

In Green building techniques | Asked By Carlton Bruen | Mar 22 12
1 Answer

How to calculate Floor Insulation Effective R-Value

I have a 2x12 floor system with R-19 supported by spring wires every three feet or so. The insulation is 5" from being in substancial contact with the floor. What is the effective R-value and what publication can I point to for substantiation.

In Energy efficiency and durability | Asked By Tyson Pischel | Mar 23 12
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