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3 Answers

Recycled barn home - vented cathedral ceiling?

Zone 6A NE Pennsylvania. In the design stage of building a home from a restored barn frame. Ceiling will naturally be cathedral the roof system is a complete straight shot from the eves to top ridge. I would like to use recycled poly iso - if there is a better type please suggest. Start with a 1" air space between the 7" of poly iso and sheathing using "sticks". Poly iso would be placed between the 2x12 rafters. Then a 1-2" layer of closed cell spray foam bringing the R value to 49 or above.

Asked By matt bowman | Feb 22 13
10 Answers

Interior insulation (in stud bays) when we have exterior insulation?

This is a follow up to the question we posed here but our problem is a little different. Here are the relevant details of our house:

We're in Zone 5A, building a new house which has already begun construction. We're nearing time for insulation, and realizing that we cannot afford the blown-in cellulose we were planning on using with a Membrane vapor retarder.

Asked By Cathy O | Feb 25 13
41 Answers

Termite and insect infestations using external rigid foam at the foundation

I am planning on a home in the Cleveland TN area and want to reduce "conditioning costs" to a minimum (<$50/Mo for all but water).

I want to use cc slabs (4 - 6") on the exterior of the foundation (full hight) but have been personally plagued by termite and carpenter ants in every home I have lived in. Short of soaking everything in dieldrin (hard to come by these days but worked beautifully in MO and has some nasty side effects), what is the current recommendation for stopping the critters outside the foam/concrete interface.

Asked By Ralph Hertlein | Feb 3 13
7 Answers

WRB detail with exterior foam and strapping


Asked By Jeff Nelson | Feb 19 13
3 Answers

Roof sheathing - TechShield versus Zip System

We are building a 1,600 sq. ft. addition; it is being added to a 1930's farmhouse in the Richmond, VA area (Zone 4, mixed humid). Detail summary: walls are 6 1/2" SIPs, truss roof (see attached file) with partial cathedral ceilings (1 ft. extra heal height for insulation), roof insulation planned is blown-in cellulose (vented attic), conditioned crawl with 2" thermax at interior foundation walls, etc.

Asked By Greg Magnus | Feb 14 13
1 Answer

Can formaldehyde offgassing from OSB boards be deterred with Sheetrock and sealant?

I am planning to convert our newly built garage into a Tiny House. But, I have come to find that I have a real problem with the off gassing of formaldehyde from the OSB boards. I installed an ERV, the air exchange has been happening for several weeks now, but the fumes are just as troublesome. My next plan is to paint the boards with SafeCoat Safe Seal.

Asked By Diane Hoglund | Feb 13 13
15 Answers

Ineffectiveness of increasing R-value with more than 4 in. of closed-cell spray foam?

I have been told a number of times that using more than 4" of cc spray foam (in a wall or roof assembly) has little value at increasing r-value. In other words, does using more than 4" not have a linear increase in r-value? The reason I ask is b/c I need the recommended r-35 against the bottom of my roof sheathing (with blown-in cellulose in the remainder of my cathedral truss) to prevent the roof sheathing to dip below the dew point and create condensation. Any thoughts? Thanks.

Asked By Matthew Michaud | Feb 2 13
1 Answer

Wall insulation/ventilation region 6 A

I am wondering if anyone has come up with a formual that calculates the minimum stand off for a canadian rain curtain that take into account the exterior wall insualating materials, r value, max. wall ht and building location/elevation?

I am also trying to locate some information relating to any benifits to reduced energy consuption a raincurtain might add. Feedback from my clients has been all over the place on the retoros we have completed and they most likely also include upgrades to the roof & attic insulation at the same time



Asked By Matt BLANC | Feb 2 13
5 Answers

Heat pump compressor in unconditioned /isolated / vented basement?

Could this work in cold climate 5? Bsmt floor Sealed and thermally broken from upstairs units. Would a Vented basement make that possible?

Asked By matt berges | Jan 30 13
1 Answer

What is the best way to build and insulate a bay window in new construction?

I have two bay windows to build and I want to keep the insulation levels consistent. I using 1 1/2 exterior rigid foam with lap siding on the exterior and 2x6 framing

Asked By Dan Easton | Jan 30 13
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