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4 Answers

Open vs. closed-cell foam in an unvented crawl space

After speaking to several spray foam contractors about enclosing the crawlspace on our 1950's home in Zone 4 (Washington, DC) there seems to be no consensus on whether it is best to use open or closed cell foam on the interior walls. The walls of the crawlspace are of block construction and the floor is dirt. Your thoughts please....

In Energy efficiency and durability | Asked By Woody McMahon | Jan 7 14
6 Answers

ICF R-value

I have a choice to make between ICF and conventional build with exterior foam.... My builder has a block available to him that is rated at an R-30. Or I could build 2 by 6 with BIBS and exterior foam to an R-38 value ...

I am in Peterborough, Ontario, which is considered a climate 6...

The builder is experienced in both methods of construction and is convinced the ICF R-30 will outperform the traditional method of construction at very little cost difference ...

His blower door tests are always less than 1 ACH50...

In General questions | Asked By bob holodinsky | Jan 7 14
5 Answers

When are cold climate Air>Water Heat pumps coming online in the US?

I live in a marine cold climate in AK and have been looking at a heat pump system that will tie in w/ my existing hydronic system.

In my research I have found some Chinese models (with little info on them available) and some great models that are sold in Europe.

Specifically the :

Mitsubishi Ecodan
Fujitsu Waterstage

Any idea when any of these will get a UL listing? Are there any existing models (besides Daiken) that work for cold climate and are air>water?

In Green products and materials | Asked By Kevin Lauscher | Mar 5 13
1 Answer

Is a slab floor a good idea for a mixed mid-Atlantic climate with marine clay soil?

Basements in this soil tend to have problems with changes in moisture resulting in clay expanding and contracting causing foundation cracks or water problems.

In Energy efficiency and durability | Asked By Pamela Smith | Jan 7 14
3 Answers

PERSIST Eave Section Reivew

We are building in SE Michigan (Zone 5) and after months of research on this site we are looking to finalize our section.

We plan on doing a PERSIST/REMOTE wall section and are struggling coming up with a large eave that we can attach outside the envelop. I have included sections for metal and shingle roofs. The metal furring seems less costly than covering the roof in another layer of sheathing....

We are mainly looking for advice on the eaves, but any other advice on the section would be helpful.

Thanks.

In Plans Review | Asked By Eric Burhop | Jan 6 14
2 Answers

Does using Knauf Ecoseal allow the house to breathe?

I live in Alberta, Canada, and am building a new house. The builder introduced me to the Ecoseal product which sounds great. As my knowledge on construction is limited, I have a question. If there is Ecoseal applied and batting along with a vapour barrier, can the wall still breathe to eliminate moisture, thus not having mold concerns 5 years down the road like open-cell foams?

In Green products and materials | Asked By Ash Bryks | Jan 6 14
7 Answers

New Construction

This site has been invaluable as I attempt to educate myself with respect to designing and hopefully building (with plenty o' help) a 1500 sq. ft. passive solar home.

Here are some details of the current design. See conceptual pictures.

> Climate Zone 5A (Rochester, NY)
> Shed roof. Standing Seam Metal roof with air gap/rain screen
> OSB-SIP walls and roof (R=52 for both)
> Frost-protected shallow foundation, concrete slab on grade
> South windows triple-glazed, high SHGC>0.5, fiberglass (not sure on manufacturer)
> Lunos e2 ductless HRV (2 or 3 pair)
>: Main floor with loft

In General questions | Asked By David Mancuso | Jan 4 14
7 Answers

New Construction

This site has been invaluable as I attempt to educate myself with respect to designing and hopefully building (with plenty o' help) a 1500 sq. ft. passive solar home.

Here are some details of the current design. See conceptual pictures.

> Climate Zone 5A (Rochester, NY)
> Shed roof. Standing Seam Metal roof with air gap/rain screen
> OSB-SIP walls and roof (R=52 for both)
> Frost-protected shallow foundation, concrete slab on grade
> South windows triple-glazed, high SHGC>0.5, fiberglass (not sure on manufacturer)
> Lunos e2 ductless HRV (2 or 3 pair)
>: Main floor with loft

In Plans Review | Asked By David Mancuso | Jan 4 14
1 Answer

Best way to insulate a cathedral ceiling?

My son and I are building an A-frame at 9,000 feet in Colorado. I am very concerned, as a California and Caribbean-type of person, about how cold the winters are and want to be warm at least when inside. I do not want to spend all my income on heating 7 months out of the year.

In Energy efficiency and durability | Asked By susan Reycroft | Jan 6 14
1 Answer

Solar roof shingles

Why does your search engine produce a "no result found" response to my "solar roof shingles" inquiry? Really, no such thing as solar roof shingles?

Maybe you could send me info and links or contacts for sourcing the highest tech versions or what I know exists :solar roof shingles. I hear the The Japanese are producing a super efficient version.

Where can I find the most efficient solar roof shingles? Tech features, product sourcing, installation techniques?

In Green products and materials | Asked By david clerk | Jan 6 14
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