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19 Answers

I am building a home with a conditioned attic. I will be spraying 11-12 inches of open cell foam underneath the roof sheathing. I need to allow the sheathing to breathe to the exterior, for it will not breathe to the interior with the 12 inches of foam. Thus, I was wondering if anyone was aware of a roof underlayment (other than building paper) that is breathable, durable, and that has a high exposure rate.

In Energy efficiency and durability | Asked By JAMES MOYER | Jul 22 09
4 Answers

I had a new central air installed, and the gas line is against the flue on the heater.

In Building Code Questions | Asked By MARK ALATORRE | Jul 23 14
3 Answers

Hello,
I currently building an addition and plan on putting up a knotty pine tongue and groove (1x6, 3/4" thick) ceiling attached to the bottom of scissors trusses. The trusses are 24" on center. I plan on putting up 5/8" drywall first to get an airtight assembly. The tongue and groove pine is end matched (ends are tongue and groove as well). My question is this, with the drywall up, am I ok not ending each piece of pine on a truss seeing that the ends are also tongue and groove, or am I asking for trouble if the boards aren't nailed on the ends?

In Interior design | Asked By SCOTT KOONS | Jul 23 14
5 Answers

I am about to start framing up walls for my woodshop. The existing slab slopes from back to front a total of about 4" over the length of 28'-0"....yes, 4". The concrete crew did a terrible job. I need some advise on the best/most efficient way of dealing with this slope in the slab when framing the walls. I feel a tight connection with a PT sill plate to the slab is crucial. So, I could:
1) Frame walls square on ground and then deal with space between PT seal plate and bottom plate of wall with large shims. Doing this though, I worry about a good connection to the sill plate.

In General questions | Asked By Zane Morgan | Jul 23 14
3 Answers

Which type of spray foam is recommended, open or closed-cell?

I'm about to remove my blown-in insulation out of the attic, and I was trying to figure out which product is recommended -- the open or the closed-cell?

In Energy efficiency and durability | Asked By TERRY KELLEY | Jul 22 14
7 Answers

I am in the process of fine tuning the details of a one and a half story house I would like to build next year. It will be in Northern New York on the border of the 5A and 6A climate zones The upstairs has a knee wall and a couple access doors to the attic space. I think I have decided to just run the zip-system up the walls and around the top of the roof rafters to simplify the air sealing.

In Energy efficiency and durability | Asked By Dillon Vautrin | Jul 23 14
3 Answers

Given all the complex issues covered on this site, this question might seem rather pedestrian....

I am not going to change out the doors on my house, but I would like to get them more airtight. In particular, I have two sliding patio glass doors, and my front door is a wood double door that has one door latched into the other (double swing in without a jamb piece between the individual doors).

In Green products and materials | Asked By Steve Young | Jul 23 14
2 Answers

I am looking to use a detail similar to 4-05055 - metal roof/unvented/cathedral/exterior 4.5" rigid insulation. I have a few questions on the assembly:
1- are the layers of rigid insulation adhered together?
2- what type of fasteners are being used to go thru the first layer of sheathing, thru 4.5" insulation, 2nd layer of sheathing and into rafters? spacing? (I am located in NY - 90 mph ground wind)
3- do you know a relative comparison between this detail and using a SIP panel - cost? installation? structural?

Thank you!

In Green building techniques | Asked By Linda Zwart | Jul 23 14
2 Answers

Thanks Mr. Holladay for responding to my question however I don't think I was clear with my question. I wanted to remove the floor installation it my atic and replace it with foam installation between the rafters. I've heard many different things about open & close cell that I didn't know what was true or false. What is recommended for the atic ceiling, open or closed cell. What is R value and what number should I try to accomplish with the R value.

In Energy efficiency and durability | Asked By TERRY KELLEY | Jul 23 14
4 Answers

Has anyone recently imported high performance windows to Canada? I'm currently looking at both Canadian and European windows for a house in southern Ontario and would be very interested to hear about any experiences, good or bad, that the GBA community has had.

On a side note, the Canadian market for high performance building products seems so small that finding local dealers for many products seems tough. Other than ordering from Small Planet Workshop or Four Seven Five, are there any good sources out there?

In General questions | Asked By Graham Fisher | Jul 22 14
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