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8 Answers

Will open-cell foam seal ceiling & present no rot issues?

Can open-cell spray-foam do all the air sealing in a ceiling & not present any rot issues? I'm concerned about it's ability to hold water as opposed to closed-cell foam.

In General questions | Asked By Eric Mikkelsen | Oct 5 12
1 Answer

HRV Design

Hi I had a question about my HRV, I installed exhaust ports in the bathrooms and fresh air to the living, bedroom areas. I have a cupola on the center of the house which is about 5' by 5'. The cupola shaft runs down through the house and I'm wondering if I should install an hrv port as high as I can to regain some of the heat that will be traveling up there? Around the cupola is insulated with 2' hdsf and dense pack cellulose.

In Mechanicals | Asked By Mark Hinkley | Oct 5 12
7 Answers

Should I replace rolled roofing on flat roof carport with metal or rubber roofing?

My widowed mom was the victim of a sham roofer after some hail damage. A carport my dad built in 1962 had been fine all these years with rolled roofing. Major leaks after shoddy repairs have caused her to have to have some folks give estimates. One man says he will replace it with metal roofing and one says commercial rubber roofing. The first man's cost is $900 and the 2nd is double that. Is there a general consensus about either of these?

In General questions | Asked By Robin Johnson | Oct 2 12
10 Answers

How much for damp-spray cellulose?

Can anyone with experience contracting damp-spray cellulose please tell me what it costs generally? Some project details would also be helpful. I'm researching a story for Fine Homebuilding magazine and it's tough to get pricing for damp-spray.

In Green products and materials | Asked By Patrick McCombe | Oct 3 12
4 Answers

Basement & double stud wall concept

Rim joist and floor decks are usually full of thermal bridging & moisture hazards.

In Energy efficiency and durability | Asked By Jerry Liebler | Oct 2 12
2 Answers

'Smart': s-m-r-t...

Hi again. i have heard of OSB panels, et al, as being a 'smart' vapour barrier/retarder in that it becomes more vapour permeable the wetter it gets. assuming 'smart' is a good thing, why is it a good thing that a vapour barrier becomes more permeable the wetter it gets?

In General questions | Asked By erik olofsson | Sep 29 12
8 Answers

Cross Laminated Timber anywhere?

Hi there
Is anybody aware of a US or Canadian manufacturer (not an importer) of cross laminated timber panels? We would love to use them on a few apartment buildings...

In Green products and materials | Asked By sam bargetz | Jun 15 12
0 Answers

Attaching vapor barrier to ye olde stone foundation, oh and there's rats

One of the things I think we don't talk enough about is rodent-proof construction. It's just a skip and a jump away from air-tight construction, and I think we should be marketing and selling this.

Anyway, here is the problem I'm having combining rodent-proofing strategies with air sealing and insulation strategies.

In Energy efficiency and durability | Asked By Stacey Cordeiro | Oct 3 12
4 Answers

Enclosed "3-season" porch in front of 16 foot sliders

Enclosed "3-season" porch in front of 16 foot sliders: Where to put maximum r-value?

In Green building techniques | Asked By Michael Arnold | Oct 2 12
1 Answer

How do you protect from termite or carpenter ant infestation between the sill plate and an ICF basement? I am in zone 7b.

The termites could use the foam as a pathway into the house. Without stripping the foam from the top part of the basement wall, how are the termites forced to the exterior?

In Energy efficiency and durability | Asked By Tadd Wilson | Oct 2 12
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