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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
5 Answers

Photovoltaics: String vs. Microinverters

CZ-4. Southern Indiana. New Construction Ranch. Garage Roof faces 30 deg west of south (210 deg). NO shading from trees now or in future. About 36 Grid-Tied Panels. No battery back-up. A purchase arrangement, not a lease type transaction. Three major installers in the metropolitan Louisville, KY market.

Two competing PV installers. One for Microinverters ; one for Strings with single inverter/optimizer.

In Energy efficiency and durability | Asked By Ted Cummings | Apr 30 16
0 Answers

A temporary situation for new people registering on GBA

As our I.T. team tries to find a good way to block Chinese companies which have been flooding our site with spam, we need to temporarily stop accepting new registrations for the GBA site. (I'm talking about the free registration that is necessary before you can post a question or post a comment.)

We anticipate that this situation will only last for a few days. Once we get a handle on a way to fix the spam problem, the site will once again accept new registrations.

Anyone who wants to become a GBA subscriber can still subscribe at any time.

In General questions | Asked By Martin Holladay, GBA Advisor | May 2 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
6 Answers

Preparing for future solar panels

Building a new home and want to install solar panels at some point in the future. They won't be in the budget initially, when the house is built, but I want to prepare for them and make sure I don't miss something during the construction process that I will have to redo.

The panels will not go on the roof, they will go out in the yard or on an outbuilding or pergola, so I don't have to worry about running wires from the roof to the basement. However, do I need a particular type of breaker panel? Do I need to spec certain equipment?

In Green building techniques | Asked By Clay Whitenack | Apr 25 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
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