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2 Answers

Looking at using black sheathing for air sealing /baffles cathedral roof

I'm looking for a materiel to constuct some homemade baffles to provide an air gap for a dense packed cathedral roof. The trusses are 32" inches tall with a 1/2 inch plywood deck on top. I understand the need for a gap to allow the deck to dry to the soffits. I'm looking for a material that is permeable enough to allow the cellulose to dry to the gap while providing an air barrier as well. I was looking at this
http://bpcan.com/en-CA/products/insulation-and-structural-boards/composi...

In Green building techniques | Asked By Geoff Frood | Nov 26 14
3 Answers

Brands of HRV?

Anyone have any experience with either Lifebreath or Imperial HRVs? My architect specified Zehnder, but my HVAC guy has installed Lifebreath and Imperial, but not Zehnder.

In Mechanicals | Asked By stephen sheehy | Nov 17 14
2 Answers

U value of double windows for sound proofing?

Hello, I've just recently seen a soundproofing technique where and inner and outer window are installed in the same rough opening with a very large air gap between them (4-6"). What would the U-value impacts be of such an arrangement? Is there a way to calculate this outside of doing a labratory test? Let's assume two double hung windows with U= 0.30 ea. Does the air gap do anything for thermal performance as it does for sound?

Also, if the interior space is as air sealed as can be with normal installation techniques, will these get condensation build up?

Thanks,
Ryan

In Green building techniques | Asked By Ryan Griffin | Nov 26 14
3 Answers

Any good thoughts on Drolet wood stoves?

A relative is asking about efficient wood burning stoves. Any thoughts. I would never burn wood outside an occasional campfire using up leftover 2x4 cut offs. I told him any Canadian company can't be all that bad and it the 2000 is EPA rated whatever that means...

Any recommendations would be greatly appreciated.

Thanks,
PK

In Energy efficiency and durability | Asked By Paul Kuenn | Nov 23 14
9 Answers

1.5" of rigid insulation over stucco; polyiso or EPS?

I have a stucco house in high desert New Mexico (zone 5B). The stucco is in bad shape after having been terribly abused by the previous owners, so I'm taking the opportunity to have the whole house wrapped in continuous rigid insulation as part of the re-stucco project. The boards would be applied over the existing deteriorating stucco, fastened through it and the sheathing and to the studs, and then a new 1/2" two-coat cementitious stucco cladding will be attached over it.

In Energy efficiency and durability | Asked By Nathaniel G | Oct 2 14
10 Answers

Designing a passive solar / net zero house in NC Mountains

My wife and I are designing a new mountain home in Banner Elk, NC. We are in the initial design stages with our architect and are confused by the numerous options to consider. Our house will be built in the Eagles Nest community which has a pacific northwest lodge feel. Our home site is at a 5,000 foot elevation on the mountain ridge with a northern view.

In General questions | Asked By bill Moseley | Nov 23 14
5 Answers

Locating flue hole without removing wall paneling

I am trying to install a wood stove in a room that has paneling on the walls. The chimney flue has been covered by the paneling. I'd rather not remove the paneling because it was glued to the wall when installed. I have tried several ways to do this but was not successful. I dropped a measuring tape down the chimney, took a measurement but was way too low for the flue when I laid the measurement out. Check the room next to this room and found the chimney and a sealed flue on the opposite side of the chimney. Thought about knocking out the plaster or concrete seal, still an option though.

In Green building techniques | Asked By Louie Bruno | Nov 19 14
2 Answers

What U and SHGC is needed in temperate weather conditions to achieve NetZero?

In this wonderful community, Energy Efficiency is often been in reference cold climates. I live in California and am in the architectural stages of building a NetZero house.

We have two seasons: Summer and Rainy. The rainy season lasts from November to end of Feb and during those months it can actually freeze - although I doubt if we ever have more than 5-6 freeze days a year. In the summer we never have more than 5-6 days above 90 in a year. We probably have at least 330 days of sunshine.

In Energy efficiency and durability | Asked By Katherine Bretz | Nov 24 14
2 Answers

Dense pack Q: Can fiberglass batts be extracted without demo'ing a wall?

OK, a few more insulation questions more question, then I think I've hit my quota for the week (year?) :) I want to learn a bit more about dense packing a wall just so I have that as a data point to make my final decisions.

In Green building techniques | Asked By Ryan Griffin | Nov 24 14
3 Answers

Blow cellulose into air space between 4" gap from floor to slab? Other options?

Hi, love this place, it has answered so many of my questions but this one I'm stumped on.

In General questions | Asked By Luke Kelly | Nov 25 14
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