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1 Answer

I'm looking to buy 3" polyiso from a local seller that is reclaimed from commercial roof tearoffs. Two Questions: 1. The seller says they have a hard covering on one or both sides. I've used foil faced polyiso, but am not familiar with the hard covering that (I'm assuming) is used in commercial roofing. Any problems using this as outsulation on a house? My thought is it can't be any less vapor permeable than foil faced, so it should work the same from that standpoint. How about difficulty of installation with the hard covering?

In Energy efficiency and durability | Asked By Bill Costain | Oct 14 11
8 Answers

In general, where have you found the best price on XPS and Polyiso? Lumber yard? Big box stores? Other? We are in the design stage of a new custom home project and I want to analyze price/performance as we are creating the plans. In the past I have relied on my stucco sub to provide it in his bid, but we will install on this project. Thanks for your input!

In General questions | Asked By Bill Costain | Oct 11 11
4 Answers

I plan to insulate my now uninsulated poured concrete basement walls. I think I have a pretty good idea of how it should be done using XPS on walls and floors, wood framing inside the foam and with further insulation between the studs,, with a code compliant fire "retardant' cover like drywall. I base my plans on research here, at Fine Home building, and at Building Science Corp.

In General questions | Asked By Andrew Alden | Oct 13 11
5 Answers

I have a 54 year old Cape style home in Nerw England. Plaster ceilings run along the base of the roof rafters (2x6 rafters). No soffits - have Hicks vent drip edge & Full ridge vent. Need to re-roof, want to add insulation, build out vented soffit system,- by adding rafter tails, extend the rakes out, Ice & water 6 feet from edge & valleys then re-roof.

In General questions | Asked By John Shea | Oct 10 11
3 Answers

I am in the process of buying a 1,400-square-foot home in Zone 4 (mixed humid climate). The existing wall section is: brick veneer, 1" air gap, tar paper, plywood sheathing and 2x4 walls.

Most of the deep energy retrofits I have researched include installing exterior rigid insulation, which is probably out of the question for me given that I would either have to tear the brick down or bury it under the insulation and new cladding. So I am considering creating a double-stud wall on the interior at a total depth of 10", then filling with dense pack cellulose and airtight drywall.

In Energy efficiency and durability | Asked By Charles Chiampou | Oct 12 11
5 Answers

I live in a home in NJ (4A/5A climate zone border) with a 3rd floor wooden deck over a a slightly pitched flat roof with conditioned living space below it. This deck was built about 7 or 8 years ago, and is supported by 4x4 posts which are going through the roof and on top of the rafters on the second floor. The ceiling on the second floor is leaking now, and I'm pretty sure the deck isn't too safe.

In Green building techniques | Asked By Armando Domingos | Oct 3 11
5 Answers

If the goal of PEX manifold systems is to save energy and wasted water on the hot side do you really need a manifold for the cold line? I appreciate the organization and straightforwardness of the manifold system. But if it doesn't have energy saving potential on the cold side wouldn't it be more beneficial, in terms of materials costs, to run trunk and branch on the cold side and manifold on the hot? Are there any issues with this?

In General questions | Asked By Charles Chiampou | Oct 12 11
16 Answers

Hi all,

Another forum reader and I were discussing a detail last night and he suggested I open it up to the board, so have at it.

Between a recent bump of Thorsten Chlupp's JLC article and a recent thread on avoiding adhesive between plywood sheathing and wall studs, I've come to the conclusion that for the small building that's underway in my yard, I'll see good airsealing results from 6mil poly, adhered at edges and openings, around the walls and another layer lapped over, across the ceiling.

In General questions | Asked By Minneapolis Disaster, 6B | Oct 7 11
3 Answers

Hi, I live in Saskatoon, Canada. Our climate is considered humid continental - warm summers and very cold winters. I need some advice quickly if possible as to whether it is okay to pour concrete up to the level of our foundation to grade water away from our house. Our neighbor is away while their newly built house is being landscaped. I came home today to find that their contractor had done prep work to put a concrete pad between the two houses to carry rain water out to the front of our properties and to the street. This is something we had discussed but not finalized.

In General questions | Asked By Colin Kindrachuk | Oct 12 11
2 Answers

I live at the border between zone 4a and zone 5a in Kansas City. My home has a barrel vault (see photos) with sheetrock following the curve on the inside, 6 in rafters withR-19 fiberglass bats, unvented, and then the decking and roof.

We are planning to replace the roof, likely with standing-seam metal. Is there any insulation that we could put on the deck under the metal, or any other ideas to improve efficiency when we replace the roof?

Thanks for your suggestions.

In Energy efficiency and durability | Asked By Tim Dellenbaugh | Oct 12 11
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