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4 Answers

Exterior rigid insulation - semi-permeable EPS with poly vapour barrier

We are currently working on two residential projects where we have specified exterior rigid insulation over a 2x6" wood framed wall. Both projects occur within Climate Zone 5 but they also have very different amounts of annual rainfall (260mm in the interior of British Columbia vs 1650mm closer to the coast). The wall assembly looks like the following in both cases with the minor difference of the insulation in the stud cavity.

Exterior Wall Assembly
- Cement Board or Cedar Cladding
- 1/2" Plywood Strapping - Rainscreen

In Energy efficiency and durability | Asked By Brett Sichello | Jul 31 14
2 Answers

Interior design in office space

Hey there,
I work with a company in San Francisco. We are trying to redesign the interior of our office space greenly and effectively.

Does anyone have any tips or tricks on doing this sort of thing?

We have no shortage of solar panels but are trying to figure out what to do with them to create a great office!

In Interior design | Asked By Adam Lawrence | Aug 1 14
1 Answer

Combustion air requirements

Without getting into the other air intake possibilities...code requires that the outside air intake ducts be covered with no less than a 1/4" screen. My concern is that there are a lot of bugs, mold spores, etc. that are much smaller. There's no way to fit this with a filter?

More details:

In Building Code Questions | Asked By Jim Johnston | Aug 1 14
1 Answer

GBA subscription: can't get connected--can you help?

Hello:

I have emailed the GBA contact twice and I have called several times to no avail. I will not leave a call back number, so they must pick up the dang phone when it rings. We used to do that in all the offices I ever worked in, but not anymore I know. However, they could at least answer my email. All I am trying to do is order a subscription. I tried using the website and it does not work for me.

In General questions | Asked By Anne Nelson | Jul 31 14
37 Answers

Exterior rock wool insulation with batts?

Hello folks,

First, I'd just like to say how thankful I am for the invaluable resource that is GBA. I spend A LOT of time reading the blogs and Q&A and I find that pretty much any question I might have has been covered here already. Though sometimes my understanding gets a little vague regarding certain details so I am hoping for some input on a potential wall detail.

In Energy efficiency and durability | Asked By Noah Byler | Jul 23 14
16 Answers

Clothes dryer preheater?

I found that patents exist for products that would use the outgoing heat from a dryer to preheat the incoming air, but I haven't found any thing forsale. I'm not going to get away from using my dryer in the winter, but I'd like to do it as efficiently as possibly. Taking warm air from the laundry room, heating it, and then sending it outside, only to have make up air come from the cold outside seems horribly inefficient. My house is much too humid during the winter to use a dryer diverter and the smell is terrible, so that's not going to work.

In Energy efficiency and durability | Asked By Calum Wilde | Jul 30 14
2 Answers

Can I sell used vinyl siding?

I am a siding installer and I would like to know if I can get paid for my scrap siding.

In General questions | Asked By Bradley Wheeler | Jul 31 14
2 Answers

Pole barn ceiling

Climate Zone 6B

In Green building techniques | Asked By JMS Build | Jul 30 14
1 Answer

Capillary break over footing vs. vapor barrier under footing

Many building science resources recommend installing a capillary break over the footing (between the footing and foundation wall). Is there a reason this is preferable to installing a vapor barrier (i.e. 6 mil polyethylene) under the footing, up the inside face of the footing, and overlapping with the under-slab vapor barrier?

I'm assuming the foundation wall waterproofing extends all the way down the exterior face of the footing. I'm in Cincinnati, OH, and my question applies to finished basements, unfinished basements, and conditioned crawlspaces.

In Green building techniques | Asked By Eric Stear | Jul 31 14
8 Answers

Foil faced ISO over 3" closed-cell spray foam?

Looking for an answer before I start this project. I live in northern MN. I had my attic spray foamed 4" behind knee walls, 3" in the living space. This is a 1 1/2 story with a non-vented roof. I want to know if its O.K. to use foil faced 1" rigid sheets to cover studs [Editor's note: I think David means "rafters"], with the foil facing down between the knee walls. I did plan on filling all voids and foil taping the joints. Then 1/2" sheetrock over the foam. Just want to make sure this isn't considered a double vapor barrier, and if this would be considered good construction.

In Energy efficiency and durability | Asked By david chinn | Jul 27 14
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