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7 Answers

Stress question

I want to use a 2x4 wall as my load bearing wall (parallel to the ridge line) supporting trusses. Because I'm using cantilevered truss s to cover front and back porches I have unusually long truss s (56') and am building where the code requires design for 75#/sq ft snow load , I'm investigating loading and stress. The load bearing wall is the inner of a double stud wall and is sheathed on it's outer face with 1/2" plywood sealed as my primary air barrier. If I frame the wall 16" OC it can easily support the snow load + dead loads.

In General questions | Asked By Jerry Liebler | Mar 7 13
2 Answers

Roof and attic

Hi. I have a large attic which has staircase access. There is also an air handler in the attic, and the ductwork is mostly in the rafter bays of the roof. I have lots of air seal-penetration types of issues in the attic floor that need to be addressed as well.

I would like to finish the attic. So, the question is... what's the best way to insulate?

In Energy efficiency and durability | Asked By nj shore home | Mar 12 13
1 Answer

What are the best brand windows to use in Zone 6a?

What would be the best type, brand, style, windows to use for the money?\

In Green products and materials | Asked By tom massman | Mar 13 13
4 Answers

Trading Roxul for plastic foam in basement wall insulation.

The usual advice for interior insulation of basement walls is use rigid foam because it is not air permeable so condensation will not occur. Cost of material for foam is near $0.12/ r sq ft. Cost of Roxul comfort bat about $0.045/r sq ft.

I will have an inner basement wall of 2x6 to support my first floor and the inner walls of the exterior double wall. My initial sketch shows 3" foam and R-15 batts with no drywall. If I switch to all Roxul I would want airtight drywall. I already have more insulation than I can justify.

In Energy efficiency and durability | Asked By Jerry Liebler | Mar 11 13
4 Answers

Where to insulate a Gambrel

I am debating on where to insulate and air seal a Gambrel roof detail....any preferences?

Thanks is advance for your input....see attached detail (sorry for poor quality)


In Green building techniques | Asked By Bruce Friedman | Mar 12 13
4 Answers

Reading list

the american philospher, john serle, once said, "if you can't say it clearly you don't understand it yourself.” i sometimes feel this way when i try to articulate the theory behind everyday building science. what books or periodical articles do you recommend to better understand phenomena like condensation and air movement; how insulation and vapour retarders work, et al...?

In General questions | Asked By erik olofsson | Mar 12 13
0 Answers

What siding over 2 inches foam and 1x4 furring? Fiber cement? LP Smartside? Cedar?

South Cental WI, 53951. Zone 6a. Currently have:
- OSB sheeting
- typar housewrap
- 1" polyiso foam, taped.
- vinyl windows installed on top of foam, flanges taped to foam

Our roof is neat standing seam in burnished slate (dark grey/brownish color). Brown facias, soffits and gutters.

In General questions | Asked By Nick Zees | Mar 13 13
1 Answer

DensArmor Plus

anyone know what tape to use for DensArmor Plus in a bathroom? the bathroom has a shower. i swear i read somewhere not to use regular fibatape but the only other non-paper tape i can find is alkali-resistant cement board tape. it looks like regular fibreglass tape but is grey jn colour...

In General questions | Asked By erik olofsson | Mar 12 13
4 Answers

Bathroom moisture control in HRV defrost mode

Planning new residential construction in moist and winter cold zone 5A.  Basement/walls/roof are R20/40/60, triple-pane, super-tight, well-drying, direct-vent, and mechanicals all in conditioned space.  I feel like I have covered most angles, and am looking for extra insurance against mold.
I'm planning for 2 mini-splits to handle 3000sf plus another mini-split for a 600sf in-law, and an HRV to not only provide exhaust/fresh air, but with the help of a few transfer grills, to also distribute heat & cooling throughout the fairly open layout.

In General questions | Asked By Bill Littlewood | Mar 11 13
3 Answers

Is anyone familiar with reflective insulation, specifically Think Smart?

I was introduced to it a a home show. The cost is about $2.75 per square foot. It seems high, but could get a 4-5 year payback. Comments please.

In Energy efficiency and durability | Asked By Tom Swanson | Mar 11 13
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