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3 Answers

Certainteed cement board siding

I am building a new home in zone 6. I was considering using a cement board siding product. I am aware that Hardy Board has been out for quite some time and that there have been some product issues in my area . My building contractor is a Certainteed Pro installer (Vinyl siding) so I am wondering about the reliability of the Certainteed product. I read that there were some class action suits back in 2010 in regard to this product. Does anyone have any experience with these products.

In Green products and materials | Asked By Dana St.Ours | Jun 14 12
6 Answers

EPS over concrete filled concrete blocks

New construction, concrete block filled with concrete and rebar. Would like to have 4 inch EPS (2 two inch layers). Recommendations for securing foam to the concrete block, vapor barrier placement, and proper method to attach siding over the foam.

Thanks, Kevin

In Energy efficiency and durability | Asked By Kevin Lesh | Jun 9 12
4 Answers

Indoor Swimming Pool Wall Detail

I have been asked to finish an indoor pool that was built about 18 years ago. The building has stood up well and the only signs of damage were from water intrusion at an exterior door. The building was not heated and the pool was not heated during this time with exhaust only venting, which is why I believe there has been no notable moisture damage.

In Plans Review | Asked By Allen Loree | Jun 13 12
12 Answers

Waterproofing concrete slab

I have a large V-deck which four inches of concrete has been poured. On top of the concrete we are planning of pouring four inches of color concrete to finish the deck. Our concrete contractor wants us to put a waterproof barrier between the two concrete slabs and it has been recommended to use 60 mil epdm membrane. This seems like overkill and I was wondering if a membrane is really needed or if there is are any other waterproofing applications which will work. Your recommendations are appreciated.

In GBA Pro help | Asked By dennis levine | May 18 12
3 Answers

How to ventilate a "room in the attic" truss system

Hi. Building a two story small house - 28' x 26' in zone 4A, TN. Using a "room in the attic" truss system.

The trusses will be the 3rd story. The room in the middle will be 12' wide and the length of the house, with a window at each end. The knee walls will be 5'.

I'm not sure how to ventilate or if it's necessary. The 7' on each side that will be behind the finished room. This will be the webbed part of the trusses.

In General questions | Asked By carl mirabile | Jun 12 12
3 Answers

Cellulose insulation in new saltbox roof (Zone 5a coastal)

In order to minimize Treated Floor Area, and to simply enclose a proposed house with less volume on the second floor, I plan to use a saltbox roof. Are there any concerns with transitioning from dense pack in the unvented slopes to loose fill above the flat ceilings? Or should there be a vent channel in the slopes only that rides up higher than the depth of the loose fill?

In Green building techniques | Asked By John Rockwell | Jun 13 12
2 Answers

Conversion of crawl space into conditioned space.

I am involved in an Energy Performance Contract with a Housing Authority. In a 1960's development of 20 town house type apartment buildings (4-6, 1 and 2 story units in each each building) we have up-graded to high efficiency natural gas boilers using the existing hydronic baseboard system, added insulation to the attic, replaced doors and windows and now are facing the problem of what to do in the vented crawl spaces which contain the heat and hot water distribution systems.

In Building Code Questions | Asked By Jonathan Lagreze | Jun 13 12
6 Answers

Can you apply spray foam over exterior rigid foam?

We are planning to build a house located in Montreal where the weather in the winter is relatively cold and swings to hot and humid summers. We wanted to build a wall system of R40.

A lot of builders here in Montreal are spraying the exterior of the building with 1" of spray foam over plywood in order to prevent air infiltration and then filling the 2X6 studs with normal fiberglass.

From what I have read the 1" of exterior foam is not enough to prevent condensation issues on the plywood.

In Energy efficiency and durability | Asked By Howard Klein | Jun 12 12
8 Answers

An Idea That Maybe No One Cares About

I was just looking at the Home Energy Pros website ( I can't join, but at least I can look), and I found a short thread about sealing crawl space vapor barriers and insulation to concrete walls. There was some discussion about how to hold the materials in place against the concrete wall while the adhesives (mastic etc.) set (prior to mechanical fastening). One commenter wrote that he didn't really have a good way. I thought: Why not curtain tension rods? I mean the kind with rubber tips that adjust in length and stay in place by spring tension.

In General questions | Asked By Gordon Taylor | Jun 12 12
5 Answers

Should you insulate the exterior of a house with rigid insulation if you have spray foam inside?

A customer of mine wants rigid foam on the outside of his house to stop thermal bridging, and then wants to have either open or closed-cell foam blown in the interior.

I was wondering if that would be a bad situation for the OSB trapped between the two. What would be good ok around?

In Energy efficiency and durability | Asked By Jed Koljonen | Jun 12 12
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