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6 Answers

Shed roof to wall detail

Hi everyone,
Does GBA have a flashing detail for a simple shed roof to wall intersection?
thanks again...

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

What fasteners to use with Cedar Shingles over 1" IKO Enerfoil?

My wall composition will be: 2x6 studs, 1/2" plywood, 1" IKO Enerfoil (R7), perhaps a breathing mesh? and Cedar Shakes/Shingles. I'm wondering what you folks recommend for a fastener (length/type)?


In General questions | Asked By Evan Macdonald | Mar 5 13
1 Answer

Any ideas or experience with a desuperheater for a ductless minisplit?

Searching the web only gives a few clues. Anybody have practical experience or product/design examples??

Obviously during the summer you can get some free heat and more efficient cooling, at the cost of a small circulation pump running water to heat exchange medium connected with the condenser tubing - my thought is a braised plate seems most logical.

In Mechanicals | Asked By bob coleman | Mar 4 13
2 Answers

Metal roof details.

I am designing a house with a shed roof. There is a 2' 6" overhang to provide solar shading for the windows. I do not like the appearance of a thick SIP roof overhanging so need to provide support for the overhang and fascia/soffit details.

I am trying to keep costs down so trying to keep it simple. I also want to provide ventilation for a rain screen under the metal roof.

In Green building techniques | Asked By Stephen Carlton | Mar 1 13
4 Answers

Can spray foam be used as a WRB?

We are building a ~6000 square foot, 2 story above ground house with a 3000 sqft basement. The house is located in Montreal. The weather here can go from -25C (-13F) in the winter to very hot and humid 32C (90F) in the summer.

The proposed wall assembly from exterior to interior is as follows

5" of stone
1" air space
2" closed cell spray foam
Plywood sheathing
2x6 , 16" OC filled with blown in cellulose dense pack or blown in fiberglass
Membrain by certainteed (Everyone freaks out at the thought of not having poly, so this was the compromise)
5/8" Drywall

In Plans Review | Asked By Howard Klein | Mar 4 13
9 Answers

Sealing PEX and PVC pipe penetrations

I am reposting this to the Code section; not getting an answer in General Questions.

What do I use to meet code-required fire blocking and good weatherizing/air sealing for the circumferential individual tube/pipe and ganged tubes (a cluster of tubes), penetration gaps for PEX-to-wood (and plywood) and PEX-to-PVC pipe, and for PVC-to-wood, and PVC- & PEX-to-drywall?

With manifold distribution and multiple zoning of (1) HW heating supply and return (wall hung rads), and (2) potable water supply, there are a lot of penetration points.

In Building Code Questions | Asked By Oak Orchard | Feb 27 13
5 Answers

We have a 1st floor cantilevered balcony using 2x 225mm glulam beams, any ideas for water/weather proofing the beams?

The house is being built using 180mm sips with a block/stone and cedar cladding outer. Triple glazing, wood pellet boiler, solar thermal andMVHR. We aim to be as energy efficient as poss.

In General questions | Asked By Gill Wills | Mar 3 13
2 Answers

Critique my cathedral roof insulation (Part 2)

You might have saw my earlier thread. Here it is:

A friend recommended I make a slight adjustment in order bring down costs a bit.

For price reference:

- 32 sq. ft. @ 2" of XPS (pink foam) is - $51 a sheet. (for R-20 that's $100 (2"x2))
- 100 sq. ft. of fiber batt is $90. (R-22, i think)

Anyway here is the secondary design. I really apologize for the awfully crewed drawings but I couldn't find much other way to do it.


In Plans Review | Asked By Kevin Lauscher | Mar 3 13
4 Answers

About tankless water heaters

I have a hair salon. Will a tankless heater work for me?
Or do you know of it being used for a hair salon?

In General questions | Asked By Richard Belk | Feb 28 13
9 Answers

Humidity in Insulated Attic

I had spray foam insulation applied between rafters in my attic several years ago. My HVAC technician nephew living in Houston recently mentioned that insulated attics like mine are problematic in our hot climate because humidity can’t escape. I recently installed a hygrometer in my attic and have validated his statement. On sunny days, the attic temperature exceeds that of the house by maybe 5 degrees, but the humidity may be 10 to 15% higher. I’m expecting a much higher differential during hot, humid weather. Should I do something about this?

In Energy efficiency and durability | Asked By Dorothy Prowell | Mar 1 13
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