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5 Answers

How to fix an attempted insulation retrofit on a '70s cathedral ceiling?

I discovered this website 6 months too late!

After losing heat through a 70's era cathedral ceiling built on 2 x 8 rafters for more years than we liked to count, we decided to replace the roof, sheathing, and insulation in one operation. The area of the hip roof was bid at 2,230 sq. ft., the cathedral ceiling comprising 2,040 sq. ft., leaving a small attic space above bathroom and hallway areas under the peak.

Asked By Gregory Erickson | Dec 16 13
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.

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...

Asked By Geoff Frood | Nov 26 14
4 Answers

Most sesible heating system for a new house build on Vancouver Island

We are in the planning stage for new construction of a 2 level 2600 sqft home on Vancouver Island. As we're in the process of allocating budget we would like to know what the most sensible heating system to use will be. We require electricity to be our primary source with wood heat as back up, as we lack natural gas and propane is too expensive. We understand that base board electric is the most cost effective for install, but we're looking to improve efficiency, durability and sustainability with increasing energy costs in mind. As far as we know our options are as follows:

Asked By Blake Klopfenstein | Nov 26 14
8 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.

Asked By Jocelyn Smith | Nov 25 14
5 Answers

ThermoCore Roof SIPs - 8" Panels

Anyone here use or have any experience with the ThermoCore SIPs? They are based out of Indiana and have a 8" polyurethane SIP ( I know about the blowing agents) with a R-50 value that I am considering using for my roof. Zone 4B

Some key points:

1 - I will be air sealing all interior panel joints with a T&G connection, caulk, gasket, and finally a peel & stick tape to ensure complete air tightness.

2 - I will use an ERV

3 - On the exterior I plan on putting a peel & stick butyl membrane that is vapor impermeable and then a standing seam metal roof.

Asked By Peter L | May 5 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.

Asked By stephen sheehy | Nov 17 14
15 Answers

Spray foam insulation

I have a 100 year old house in Zone 5. There is a sunroom (approx. 5'X20') on the south side of the house which is all windows. It is built on piles (about 4' to the bottom of the joists) and open underneath with lattice. The room is open to the living room of my home and is heated by 2 forced hot water radiators. When we bought the home the floor was insulated from underneath by batt insulation and rigid insulation between the joist cavities. We had an energy audit performed when we moved in and were told this was all good. Still, the floor has always been cold.

Asked By Danny Mac | 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

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

Asked By Ryan Griffin | Nov 26 14
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