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1 Answer

Drain penetrations in a slab on grade

Hi, we are pouring a 5" floating slab on grade with several cast iron drains penetrating through the slab.

the drain lines run in the compacted fill below the 4-6" compacted gravel, 6mil vapor barrier, 2" tongue and groove xps and the 5" 4000psi pour with 1/2 radiant pex throughout.

the assembly we are planning on was to cut a hole in the vapor barrier and attatch to the cast iron pipe with tape, then cut a hole in the insulation around the pipe and fill with spray foam and finally to wrap the segment of the pipe that would be in contact with the concrete with thin foam insulation..

In General questions | Asked By Big Ern | May 2 16
5 Answers

Continuous insulation under slab

Hi all,
I am looking for some advise on the design of our thickened slab for a "pretty good house" in Kenora, Ontario (climate zone 7).
The house will be 32' x 24' with a loft. We are planning for 6" of rigid foam under the heated slab. Our designer and engineer are adament that the rigid cannot be placed under the footings and under the post. They are telling me this is against the Ontario Building Code and that the engineer will not put his stamp on it.
I am wondering if anyone else has come across this in Ontario?
Thanks.

In Building Code Questions | Asked By Adam Smerchanski | May 2 16
9 Answers

Pond pebbles instead of crushed gravel for the driveway - what to do?

Hello,
Our general contractor received a wrong kind of gravel for our big driveway install. We have 1500 sf to build and 1/2 of it is a concrete driveway and 1/2 permeable pavers. We have 2/3 of the total rock needed already on site. And that rock is pond pebble instead of limestone gravel that would have properly compacted under the driveway. Supposedly this cannot be returned. What are we to do?

In General questions | Asked By Lucyna de Barbaro | Apr 30 16
12 Answers

Insulation and air conditioning

After reading this blog I feel much more informed in a general sense about my insulation and heating/cooling needs, but I am still trying to figure out what the return on investment would be for certain applications in my condo.

In Energy efficiency and durability | Asked By Kevin Gabbard | May 1 16
6 Answers

High humidity in spray foam attic

Hello all,

Last fall I had my attic spray foamed. Warm temperatures have arrived and I am experiencing higher than anticipated temperatures and humidity in my attic.

I have 3 main questions (pertinent details follow):

1. Is a semi-conditioned attic RH in the 60 - 70% range cause for concern?
2. Should my attic be 10+ degrees warmer than the interior? It will get much warmer here in the coming months and I am worried that the attic temperature difference will grow.

In General questions | Asked By Nic Smith | Apr 30 16
2 Answers

Integrating rainwater collection system into house water faucets?

Hi all,

Building a new house and at some point I would like to have a rainwater collection system. This system would route the gutter downspouts into an underground tank and then have a pump to distribute the water around the yard.

Thinking about how to distribute the water around the yard, I had the idea to connect the tank to my house water hydrants (house bibs, outdoor water hydrants, etc.).

In Green building techniques | Asked By Clay Whitenack | May 2 16
7 Answers

Insulating floor of mudroom before closing it off

I'm building 5' by 8' mudroom addition where there previously had been a dilapidated porch-like structure. I've poured the foundation and secured the sill. The concrete foundation is about 5 inches above soil, then 6 x 6 sill. I will be framing the floor with 2x 6. I'm stuck with these dimensions because of grade etc. This "crawl space" is NOT connected the the main house's crawl space and will be 100% inaccessible once the subfloor goes down. Also, foundation is non vented.
Anyway- the plan is to-

In General questions | Asked By Joseph Moore | Apr 29 16
10 Answers

Exterior finish on 1850s farmhouse

I've got an 1850s farm house I'm in the process of renovating. The house needs considerable exterior painting.

Do you all have recommendations on the best exterior finishes for an old house like this? I could shingle instead of painting, for example, or strip and stain.

I'm hoping to create the most energy efficient old house possible with minimal future upkeep. Paint seems to need redoing quite frequently, and other possibilities would be welcome.

Thanks,

Ilmari

In Green building techniques | Asked By DJ Polojarvi | Apr 30 16
5 Answers

Re-roofing low-slope roof, unvented insulation techniques

Shed dormer on back of 1.5 story cape cod.. 20ft X 20ft roof. Low-slope, 1.5 in 12.

Little or no access to interior "attic".

2X6 rafters. "Vented" at soffit. Insulated with 4" to 10" of fiberglass batts as room allowed (done before ceiling drywall was installed.)

Re-roofing dormer. Will replace roof sheathing. Considering un-vented roof for this shed dormer. No room to add rigid foam on top of sheathing

In Green building techniques | Asked By David Heinicke | May 1 16
2 Answers

Ventilation

I am rehabilitating a 1950's shop/garage building. It has a gable roof and has a 1 foot overhang on the gable ends. The overhang was constructed with 2x4's that were toe nailed to the gable wall. On the underside of the 2x4's, a thin (1/4 inch) plywood application was mounted. I am removing all of the existing exterior wood, facia and rake boards, siding, etc, and installing new materials. My question is, do I need to be concerned about ventilating this 1 foot overhang and, if so, what is the best way to accomplish that? Thanks.

In General questions | Asked By Peter Liberatore | May 2 16
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