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0 Answers

Air Sealing Question - Assistance Requested for 6th Side of Building Envelope

My husband and I are homeowners who are working on a very deep energy retrofit of our 1860's house, almost a total rebuild. We have learned so much from this website and the Q's and A's from everyone's contributions, so many thanks to all readers and contributors. We had already started the building process when we learned of this site, and are now attempting to make accommodations for deficits in our education and processes during the early stages of our build.

Asked By Howard Lederman | Sep 14 14
6 Answers

I'm wondering if you can insulate the attic roof rafters

We are going to add insulation to the floor rafters in an attic, but wondered if we can also put batting on the roof rafters? Most videos I've seen only show them doing floor rafters. Thanks so much.

Asked By kristin burton | Sep 12 14
14 Answers

Liability insurance - what would that cover?

1. Does liability insurance cover issues related to removing improperly installed open-cell foam in an attic on the underside of a roof (i.e. all those horror stories about roof rot, or open-cell continually off-gassing or smelling weeks after it was installed, etc..)? Or is that a different type of insurance?

2. Should I specifically ask for the details in the Liability insurance to find out specifically what it covers, is that something contractors should be willing to share?

Asked By George G | Sep 12 14
5 Answers

Zone 4B - 2012 IBC and SHGC

The new 2012 IBC adoption in my future building area will mandate that windows can only have a maximum of 0.40 SHGC, including the south facing windows. I am trying to achieve a Passive House design but the low SHGC mandate makes it more difficult. I am going with Intus uPVC triple pane windows. Originally I was going to go with the 0.49 SHGC for the south elevation but now I have to go with the 0.37 SHGC. The building department will NOT budge on this factor and will not allow any windows > 0.40 SHGC.

Asked By Peter L | Sep 13 14
4 Answers

Inset 2x6 sill plate

We're in the final phases of house plans for our new build in Illinois(5A). I'm very interested in adding 2" of XPS foam, but not so excited about it extending beyond our basement foundation wall. Would it be acceptable to inset a 2x6 treated sill so that the foam does not extend beyond the 8" basement foundation wall?

I've attached a drawing to help explain...

Thanks a bunch - I really appreciate all the advice I've learned on this site!

Asked By Craig Harper | Sep 14 14
0 Answers

Roof Insulation/Decking Combination

Hello, I live in Winnipeg MB, Canada (Zone 7, North of North Dakota).

I am insulating my garage ceiling to R22+ (standard pink fibreglass between 2x8 ceiling joists). I am also looking to insulate my garage roof to keep some of the heat from the summer out of the attic space in which I will store some things that i do not want subjected to high attic temperatures (I also expect this will help keep the garage cooler as well since the attic will be only about as hot as the outside air at most.

I intent to layer the system as follows:
1. OSB as the roof decking

Asked By Mike Gagne | Sep 14 14
0 Answers

Options for air sealing T&G ceiling with no air barrier installed.

Hello all,
I apologize if this question appears a repetitive one, as I have read through a good bit of the Q&As here, but still cannot determine my best course of action.

Asked By Rob Leonard | Sep 14 14
11 Answers

Insulation question for new house build

I’m building a brick bungalow in zone 5, please help critique my insulation. The sheathing is 1” Polyiso (foil faced) wrapped in Typar building wrap. I realize the polyiso should be thicker, but I’m told it’s too late. The walls are up and the windows are purchased.

Attic - R50 loosefill cellulose

Main Floor – R22 CC spray foam in 2x6 wall with no VB, drywall and latex paint
- The other option is R10 CC spray foam with R14 Roxul and no VB.

Rim Joist – R12 CC spray foam and R14 Roxul (thermal barrier required)

Asked By Jeff Conners | Sep 12 14
7 Answers

Spray foam & wood roof deck

100 year old residence is located in Zone 5 w/i 50 ft of ocean/bay & has a 100 mph design wind load requirement. It is located high on a hill & completely exposed. Vented eave ridge is not advisable in this area do to high driven rains. The home will not be the primary residence, therefor optimal heating, venting & dehumidifying will not be maintained 24/7.

The energy code requires 49R roof assembly for the proposed occupied attic w/ cathedral ceiling. 49R requirements & existing 2x8 rafters, limits choice of insulation to closed cell spray foam.

Asked By Sheila Sullivan | Sep 12 14
5 Answers

If I have a 5 1/2 in. square framing bay and the exact same 5 1/2 inch square batt, does it matter which way I install it?

Does fiberglass work directionally? Or does it matter?

Asked By rich graves | Sep 13 14
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