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11 Answers

SIP overhang/soffit - Waterproofing

OSB 8" thick Polyurethane roof SIP that overhangs the wall by 24" - I am using peel & stick Ice & Water membrane to waterproof the roof and this roof SIP.

The build-up: For the 24" overhang/soffit, I am looking to just continue with the peel & stick/Ice & Water membrane and wrap the overhang, fascia, and underside of the SIP soffit with the same peel & stick membrane. I will then use 26 gauge aluminum to cover the area to provide protection.

The soffit doesn't need to be vented of course because it is a SIP and the peel & stick membrane provides the waterproofing.

In General questions | Asked By Peter L | Sep 6 14
3 Answers

Wood furring attachment to CMU

We are renovating a building where we are adding 2" of rigid foam to the exterior of the concrete masonry unit walls. So the wall system will be as follows from the inside surface to out;

  • 8" CMU
  • 2" Polyiso
  • 1x Wood furring
  • Fiber cement siding
  • In Green building techniques | Asked By Joshua Lloyd | Sep 9 14
    4 Answers

    How to seal and insulate an enclosed rim joist in an older balloon frame house?


    I hope you don't mind my asking this question here. I've talked with a number of contractors and gotten different answers from each.

    I recently moved into a 1930s balloon framed home in Maryland. The ground floor is quite cold in the winter, and I'm getting ready for next season. The walls are insulated with fiberglass batts; the attic has blown fiberglass to R-40 (but I don't know the extent of the air sealing in the attic, though my suspicion is that it is not sealed).

    In General questions | Asked By Joe Emerson | Sep 8 14
    1 Answer

    What's best method of converting a "semi-vented" crawl space with a rat slab w/no vapor barrier into an unvented crawl space?

    Wondering how best to handle the crawl space of a tri-level in upstate NY (built in late 70's). The house is "semi-vented" (2 vents on the east wall half covered by mulch & soil on the exterior and 2 vents going into a garage on the south wall that have been blocked off with wood). Entrance to the crawl space is provided by 2 common doors from the lower level. The house is heated with hot water baseboard, and currently has fiberglass insulation between the joists... which plays out just like you'd think - the insulation is very wet throughout the crawl space.

    In Green building techniques | Asked By Stephen Mager | Sep 9 14
    1 Answer

    Insulating an unvented low-slope roof

    Been reading through many articles throughout the web discussing the varied approaches to insulalting different roof types in varied climates with various materials. that said I cant seem to find (or may have overlooked) approached to insulating my roof.

    I live in Washington DC and here's what I have:

    Flat roof comprising of (bottom to top):
    2 x 8's;
    Plywood strips;
    2 x materials ripped to provide slope, laid on top of the plywood strips and installed to create a valley in each corner of the roof;
    5/8" CDX;
    2" thick Isoboard;

    In Energy efficiency and durability | Asked By Alexander Brace | Sep 9 14
    3 Answers

    I need to show that 4" of EPS is weather resistant

    I am working with a product from South Africa called Imison.
    Web page: http://imison.com/

    The core is 4" thick type 1 EPS panels that meet ESR1946/ASTM C578. I understand that 4" wide EPS is waterproof/weather resistant due to it's permeability rating and should satisfy the IBC in regards to being a water resistant barrier however I do not know how to prove it.

    I need to prove that the 4" of EPS resist water, however if water does get in it can diffuse out.

    In Energy efficiency and durability | Asked By Daniel Sterns | Sep 9 14
    12 Answers

    What is a capillary break between the footing and foundation wall?

    Your details show a caplillary break between the footing and foundation walls. What is it? Is it continuous?

    In GBA Pro help | Asked By Arthur Ratner, AIA | Jun 23 09
    2 Answers

    Vented crawl space insulation, Southern California

    I'm in the early stages of rebuilding my house, which happens to have a ventilated crawl space. I believe I'm in climate zone 3B, and my project manager is encouraging me to simply use fiberglass batt between the floor joists to achieve the required R-13 insulation.

    In Energy efficiency and durability | Asked By Mike Simanyi | Sep 8 14
    12 Answers

    Rainscreen siding with a very large gap

    Reading about rainscreen siding systems it seems that the recommended gaps are typically 1/2" to 3/4" between the housewrap and and the back of the siding. Is there any reason why one couldn't do a very large gap using thicker furring material? Maybe around 3" or 4" between the siding and the sheathing for architectural reasons on a remodel? Would there be problems with having that large of a gap?

    In Green building techniques | Asked By Kevin Hardy | Jul 26 14
    5 Answers

    Foam, cellulose, sealing, or none of the above? Benefits outweigh risks?

    Hi – I'm a homeowner who has spent a ton of time reading a few dozen threads here (invaluable), other posts/articles elsewhere and have arrived at a crossroads…open to advice and/or questions I should be thinking about to help me arrive at a decision. I can provide as many details as needed on my energy audit, house location/construction/details, monthly energy expenses, etc. if necessary.

    It boils down to this (Note: no need to use attic for storage/living space)-
    1. Use blown-in cellulose in attic, lots of air sealing, CC foam in cantilevers/rim joist

    In Energy efficiency and durability | Asked By George G | Sep 8 14
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