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2 Answers

Sheathing at the ridge vent

I have a 12 pitch roof with 24 OC tji rafters and 5/8 deck membrane I have a 1.5 inch air channel between the rafters that vents along a continuous ridge vent. The sheathing sets back from the ridge 2". How do I attach the sheathing membrane at the ridge set back (other than the 24 OC rafters) without impeding the air flow? Is there a metal, inverted 'U' shaped bracket that I can screw the deck to? Left unattached, compromises my shear value and will eventually sag.

In General questions | Asked By Ron Walashek | Sep 19 14
3 Answers

Insulating and air-sealing a room-in-truss over a garage

Hello,
I am looking for some clarification on insulation and air-sealing, when dealing with room-in-truss construction for a conditioned space over a garage.
I live in Michigan, climate zone 5. I have a 28x36 garage, with 28ft span 8/12pitch "attic" trusses. the trusses have a 2x10 bottom chord and 2x8 top chords with 2x4's at the kneewall. I have a permanent stairwell going to the room in the truss, and I plan to heat the room. I have in-slab hydronic heating on the garage floor.

In Energy efficiency and durability | Asked By Ben Helmreich | Sep 15 14
2 Answers

Looking for guidance on how to downsize in a green way

Hello. Am looking for some guidance. My husband and I want to sell our current home and downsize to something smaller and greener. Our budget is pretty limited, though, so we're trying to figure out what the best options may be. We will likely have to pay a fair amount just to get out of our current mortgage, pay closing costs, etc. Then we've been approved for a 150,000 mortgage and with that we could:

a. buy an existing smaller home, close to nature (though those seem very hard to find in our budget)
b. buy land and put up a modular home

In GBA Pro help | Asked By Jen Yost | Sep 19 14
2 Answers

Thoughts on insulating — renovation

I ‘m trying to decide what insulation value to go with on a house we are renovating in Toronto, ON. It’s a 1 ½ storey that we are making 2 storey with adding addition on the back and attached garage.

The 1st storey walls are to be left, 1950s double brick walls no insulation. The 2nd storey I would like to go with either 2x6 with R24 Roxul or 2x8 R28 or 2x4 x2 with 3xR14=R42 and 3”Roxul Comfort board IS R12 on the outside.

In Energy efficiency and durability | Asked By Dave Bentley | Sep 18 14
2 Answers

Where did vestibules go?

With all the emphasis on energy efficient building enclosures and air sealing, what happened to the vestibule? A fair amount of thought goes into the energy penalty small leaks represent to a well sealed house, but surely opening the main entry represents a significant air change, especially if it is windy or you are talking to someone who has knocked on your door.

In General questions | Asked By Malcolm Taylor | Sep 18 14
1 Answer

Metal building — office insulation

Architectural details indicate insulation at 16-18' ceiling heights and vertical walls with methods typical of metal buildings. Offices being built inside much like a story and a half home due to headroom at eaves verses the center of the building. Heating units and distribution is hung from roof structure above 8' suspended ceiling.

I'm of the opinion that a raftered ceiling at 10' or so with drywall and blown cellulose insulation will: -Provide a tighter envelope.
-Reduce the amount of conditioned space.

In Energy efficiency and durability | Asked By William Sauder | Sep 18 14
6 Answers

Conditioning and venting a small cellar - Western NY

Gentlement, what do you advise?

Option 1 - Supply and return of conditioned air approach: Seal the cellar and exchange conditioned air a supply and return approach using 2 or more floor vents/registers between cellar and the main house envelope. Possibly use humidity controlled booster fan in a vent.

Option 2 – Supply only, positive pressure approach: Use one vent pathway only, for pushing conditioned air into the cellar (no exchange with the house). Humidity controlled in-line vent fan.

In General questions | Asked By flitch plate | Sep 17 14
9 Answers

Most cost-effective method for achieving 3 ACH 50?

What are your strategies?

In Green building techniques | Asked By Nick Sisler | Sep 17 14
6 Answers

Tudor half-timber battens and exterior stucco — rainscreen assembly

Hi, I am having a house built in a Tudor style.
What are the effects of Tudor half-timbered battens on a stucco's rainscreen layer?

The lower half of the house will have a stone exterior.
The upper half will have a stucco exterior.

I have read the article “To Install Stucco Right, Include an Air Gap” and understand the importance of having a ventilated rainscreen gap in the stucco assembly.

In General questions | Asked By Ani Brown | Sep 17 14
6 Answers

Has the Oak Ridge study on convective heat loss in blown fiberglass been updated to cover newer materials?

I'm evaluating blown cellulose vs. blown fiberglass (Knauf Ecofill). The Oak Ridge study is often quoted regarding the drop in R-value of blown fiberglass when the temperature differential is high. However the tested fiberglass density (.4 - 5 lb/ft^3) is much lower than the newer fiberglass.

In Energy efficiency and durability | Asked By Neil Weinstock | Jul 21 14
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