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9 Answers

Poly under slab and over sill ?

We are building a super tight insulated house (passive inspired). My Q is does the 10 mil poly that we will put under the slab have to run up the interior basement walls and over the sill. Our house has a full basement, the concrete exterior has been waterproofed, insulated and back filled. Our sill seal will be acoustical sealant, EPDM gasket and PT sill. I understand the poly is a vapor barrier and the concrete is the air barrier. I have had a hard time finding info on the web about full basement as opposed to slabs.

In Energy efficiency and durability | Asked By Jocelyn Smith | Nov 25 14
9 Answers

Insulating a cathedral ceiling

I am trying to find an effective way to insulate a cathedral ceiling (with collar ties) in zone 5 south of Chicago. I have read many of the postings and have gathered much information, but am still hesitant due to the moisture drying to one side issue.

What I have is 2x6 rafters on a 4/12. I am doing a complete remodel and plan on removing the existing drywall and insulation. I want to verify the existence (or not) of ventilation chutes from eave to ridge.

In Energy efficiency and durability | Asked By jon cypert | Nov 25 11
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
5 Answers

What's a good damper for a bath fan/range hood vent?

My bath fan vent is basically a big hole in the house to the exterior and sucks air out of the house in the high New Mexico winds, which today reached 30 mph. There's no damper or air check valve or anything like that installed up there, and I'd like to rectify it. What do people use for this situation? A standard butterfly damper? Something louvered? This thing? http://www.batticdoor.com/bathfandraftblocker.html

In Mechanicals | Asked By Nathaniel G | Nov 23 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
12 Answers

What is the efficiency of gas powered infrared radiant heat?

My project: Climate zone 6A Hortonville, WI 54944 Energy source: electric or propane, no natural gas available

An earlier post about heating garage brought up the possibility of gas powered infrared radiant. I'm familiar with these devices, but I literally can't find any information from the manufacturers regarding their efficiency. They all claim to be "very efficient" for various reasons, but I can't find hard data.

Are they rated by a percent like house furnaces? I.E. Are they in the range of 80% efficient ceiling hung unit heaters?

In Mechanicals | Asked By Rick Van Handel | Nov 24 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
39 Answers

Seeking an air-to-water heat pump

I'm looking for an air-to-water heat pump and feedback from those who've used them. We have a LEED for Homes project in Victoria, BC, perfect climate for heat pump, affordability of project prohibits groundsource for 36Kbtu heat loss of 1800 ft2 home and for optimal comfort, low temp/efficiency, to avoid ducting we're selected hydronic in-slab for heating distribution thus standard air-to-air heat pump is a no-go.

In Mechanicals | Asked By Allison Ashcroft | Jul 28 09
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
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