Q&A: A Forum for Green Building Experts and Beginners

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2 Answers
Exterior rigid foam protection

Hi, I am in the middle of building a home. The contractor has placed one-inch rigid foam insulation of the exterior of the home. Vinyl siding is going over this. At the bottom of the house, where the siding stops, you can reach under and feel the foam insulation. It is about 2 feet above grade.

Do I need to seal the bottom of the foam to prevent any critters from getting in, and if so how?

In General questions | Asked By Chris Johnston | Aug 2 10
1 Answer
What are the standards and acceptance criteria for ceramic tiles used as a green building material in India?

What is the minimum requirement for shading coefficient according to LEED requirements to be accepted in a double glazed...?
I would like to know about the manufacturing standards, test values and the acceptance criteria and the requirement based on the Indian Green Building Council and also the LEED requirements to be used as a Green Building material in India

In Green products and materials | Asked By Arghya.K.Chakraborty | Aug 2 10
8 Answers
I need reliable recommendations for 8000 ft elevation windows

I need reliable recommendations for 8000 ft elevation windows in a log home construction. Location in Westcliffe, Colorado in a valley between 2 mountain ranges---high wind at times & 300 plus days of sunshine. Mostly casement windows preferred. New log home construction needs.

In General questions | Asked By Susie Harrington | Jul 26 10
6 Answers
Green building ancillary. Pond construction.

Here's a something I've had a hard time getting good advice on. Hopefully someone can help:

I'll soon be digging a pond that will rely on a dam built of clay excavated from the from the deep end of the pond.
I've read that clay should be compacted at “optimum moisture content” - whatever that is. At this time of year the excavated clay will be quite dry.
What is the “optimum moisture content” for compacting clay?
If the clay is compacted dry, will the level of compaction be very far off from where it would be if it were compacted at “optimum moisture content”?

In General questions | Asked By Lucas Durand | Jul 29 10
2 Answers
What is a safe green termite spray for the ground before pouring a concrete slab?

(Non-poisonous.)

In Green building techniques | Asked By Jon Rogers | Jul 6 09
39 Answers
Building Science Deep Retrofit Detail

Feel free to challenge me on this subject if you wish. I was reading the debate and discussion attached to one of Martin Holladays blog entries about 'Deep Retrofit' details. In the discussion following Martin Holladays blog entry, John Brooks asked a very simple question - where do you define the drainage plane on the Building Science Corporations detail? Well, I agree with BSC's initial response. The piece referred to as 'metal flashing attached to furring strips' does not need to do anymore than is shown in the BSC's detail.

In Energy efficiency and durability | Asked By Brian O' Hanlon | Jul 24 10
3 Answers
Unvented roof deck

I am finishing an existing work shop with a low pitch vaulted ceiling. There is no practical way to vent the ridge. Since it is a shop, no code applies to r -values, but we want the most we can achieve.
Here is what I am working with:
Mixed climate ( Central Virginia)
2 x 12 rafters 24" o.c. 5/8 osb roof deck, full coverage ice shield and 50yr shingles 2 1/2 / 12 pitch
~ 685 sq. ft. ceiling area
2 x 4 sidewalls 16" o.c.
Concrete slab floor ( vapor barrier or insulation under is unknown)
Sheetrock is proposed for the final wall covering
Tight budget

In GBA Pro help | Asked By JTN | Jul 27 10
0 Answers
A question about NYC asbestos regulations

I live in NYC - Queens. My architect sent an asbestos inspector to the house to inspect. I need him to give me a clean ACP5 in order for the bldg dept to issue me permits to start a renovation project.

He said the house still had the old asbestos cement.

Do I have to file with the city? I thought you needed the special contractor and filing with the city only for commercial buildings or schools and churches, not residential homes.

My neighbor is taking it down himself and putting it in plastic bags into a dumpster and then having the dumpster taken away.

In General questions | Asked By maria | Jul 27 10
3 Answers
Rehab house - wall assembly

Ok folks, give me your feedback on this one... Working on a rehab project that is in a historical area. Interior of the home is 100% gutted and open. Exterior, however, I am required to save about 50% of the existing siding. I cannot remove the sidings or trims in these areas per the historical powers. Under the siding is the normal 1x sheathing boards (run on a diagonal) like you see in a home of this age. Definately has gaps between some boards. My concern is about water getting behind the siding/trims and into the wall assembly.

In Green building techniques | Asked By Micah Hill | Jul 27 10
0 Answers
Has anyone used "Pour Foam" in a wall cavity?

I just did a quick cost calculation, and it is five times cheaper than a DIY spray foam kit. With the right detail, it would do a good job of air sealing as well.

In Green products and materials | Asked By Kevin Dickson | Jul 27 10
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