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1 Answer

Does one need to ventilate a small roof area when replacing old fiberglas insulation with closed cell polystyrene?

Thank you very much for your quick response. The bathroom tub area extends 4'6" from the back wall of the house and is 8' wide. As I stated before there is a ventilated soffit with 2" strip vents around the total eaves area of the house. The 8'shed roof does tie in to a ventilated attic space. If I am understanding correctly, it would be unwise to eliminate that part of the continuous eaves venting because the 8" width ties to an existing ventilated attic. I do not mean to be redundant and ask again, but am I understanding you correctly.

In GBA Pro help | Asked By Edward Palma | Apr 6 09
2 Answers

Is there a LEED certification program for building professionals?

I am interested in finding a educational program that may provide
accreditation in LEED construction For building professionals.

In Green building techniques | Asked By Wiliam Groves | Apr 1 09
1 Answer

Domestic hot water - tank, tankless, or combo?

What is the most efficient/cost effective method for domestic hot water? New construction, family of four with two almost teenagers?

Standard single or double high efficiency tank?
Tankless for master, tank for kids and rest of house?
And is it wise to have the ground source heat pump (being used for radiant heat system and ac) preheat the water, hold in the tank, then go to a tankless?
I know there is perfectly right answer, but are there any opinions if any of these options have some problems?


In Mechanicals | Asked By David Cook | Apr 3 09
1 Answer

Does one need to ventilate a small roof area when replacing old fiberglas insulation with closed cell polystyrene?

I have recently gutted a bathroom in my 53 year old house which had old fiberglas insulation in the shed roof and walls. The roof line is a low pitch (3/12)shed roof framed with existing fir 2x8 rafters, and ties into the main gable roof (7/12) at the eaves. I would like to insulate the walls and roof with closed cell polystyrene because it is a tub area extended out off the back wall of the house. The framed floor of the tub area is insulated with R-40 closed cell polystyrene, under 3/4 t&g plywood.

In GBA Pro help | Asked By Edward Palma | Apr 5 09
1 Answer

How do you know what the best set of systems are for the house?

Do you need to hire an engineer for possibly a lot of money? Do you rely on your subcontractors who may end of recommending what they make the most money on? Or do you join Green Building Adv. and try to figure it out yourself? I know every house, based on its climate, size, orientation and budget will be different...but when you take those things into consideration, what do you do?

In Mechanicals | Asked By David Cook | Apr 3 09
10 Answers

What tolerances are required on grade preparation for an insulated slab floor

We are building a super insulated shop(4000 sq ft) with a concrete slab floor with radiant floor heat. thermal calculations and recommendations from American Concrete Institute indicate we should put 3" of extruded polystyrene insulation and a vapor retarder topped by 8" of gravel under the 6" floor. What tolerances are really required on the grade flatness under the insulation? Our sub-contractor is is charging a lot for a very tight tolerance. also, would 3 layers of crossed 1" foam be better and more forgiving than 1 3" layer?

In GBA Pro help | Asked By Anna Johnson | Apr 1 09
0 Answers

Great green products for a Habitat for Humanity home

I am designing a home for Habitat for Humanity in a mixed-humid climate. I am trying to find great green products to use while keeping our construction cost to under $35,000. Specifically, I am trying to find some good windows and carpeting, but any other material recommendations would be welcome.

In General questions | Asked By David Quillin | Apr 2 09
2 Answers

Who Pays for Net-Zero?

Imagine a large home with a good envelope and enough PV or Wind Energy to "Sell the surplus".
Can or does "the Grid" really use the surplus?
Has the Zero Energy Home really "zeroed-out" its impact at the power plant?

In General questions | Asked By John Brooks | Mar 31 09
5 Answers

I am searching for a plastic shimming product for providing a drain plain behind vertical siding.

I know there is a least one product on the market that provides a rot proof material to use behind vertical siding. It should be rigid,(not Rain Slicker) and only about a quater of an inch thick with drain holes. Has anyone seen or heard of such a product?

In Green products and materials | Asked By Mason Lord | Mar 25 09
0 Answers

solar home for sale

Great website! I am putting my 100% solar home on the market soon and wondered if anyone has suggestions of places to post it so that a like minded person can find it. It is a real nature sanctuary on my 5 acres and I want someone with a small footprint to come and fill mine. Thanks for your ideas! cheryl@buildingmind.com

In General questions | Asked By Cheryl Nichols | Mar 29 09
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