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Insulation

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    Weather Barriers for Coastal Conditions

    According to general contractor Bill Robinson, the building industry is going through a renaissance of sorts when it comes to weather protection. He predicts that as the current best practices become standardized, even more detailed requirements will be brought back to the codes. And that's a good...

     
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    Products

    Exterior trim; housewrap

     
  • Energy & Moisture Matters

    We ask a panel of building scientists and builders — all keen, experienced observers of wood-frame performance issues — to answer some of the questions that never seem to go away.

     
  • Roof Ventilation Update

    The construction industry's leading researcher explains why what we think is true often isn't, and how some of our best hunches, based on observation of field performance, have paid off with problem-free attic assemblies.

     
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    Rain-Screen Retrofit

    Improper flashing, unprimed cedar, and a southern exposure had all contributed to a moldy mess.

     
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    Open-cell foam in unvented attics; code clarification; bees in brick; Alaska energy code

     
  • Stopping Condensation Behind Knee Walls

    Q: A house we built about eight years ago here in Tennessee has ductwork running through the space behind the upstairs knee walls. The exterior side of the framing has been developing condensation, but only in extremely cold weather. There are no vents in

     
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    A Builder's Guide to Energy Codes

    A close look at current energy codes - and where they're headed.

     
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    Insulating Unvented Attics With Spray Foam

    Closed-cell polyurethane foam provides the insulation, air barrier, and vapor retarder necessary for an unvented attic assembly.

     
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    On the Job

    Strong gable overhang; on site with Durisol

     
  • Block Walls, Vapor Barriers, and Solar Vapor Drive

    Q: With a cavity wall assembly consisting of load-bearing 8-inch CMUs (concrete masonry units), 2 inches of rigid foam, a 2-inch air space, and 4-inch concrete bricks covered with cementitious stucco and an acrylic color coat, how important is dampproofin

     
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    Robust Walls

    Contributing R-3 to R-7.5 per inch, sheet foam is a handy way to boost a wall's total R-value without adding too much thickness. Rigid foam sheathing can also function well as a drainage plane to help keep wind-blown water out of walls, and it can act as both an air barrier and as a vapor barrier...

     
  • Insulating a Block Wall

    Q. I'm renovating an uninsulated cape built with concrete-block walls. The plans call for gutting and reframing the interior and installing shingle siding on the exterior. Because the building needs to be insulated to comply with local (Long Island, N.Y.) code, I was considering adding a layer of...

     
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    Reroofing With Spray Foam

    Spray polyurethane foam is durable, has excellent R-value, and can eliminate ponding.

     
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    Backdoor: Blown Apart

    Blown Apart

     
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    Building With Structural Insulated Panels

    SIPs produce a tight, well-insulated shell that takes less labor to construct than an equivalent stick-framed building.

     
  • Substituting Synthetic Roof Underlayments for Housewrap

    Q: After stripping the original siding from a 30-year-old house, I'm being asked to re-side with 4x8 and 4x9 fiber-cement panels designed to look like stucco. The installation instructions permit caulking at the vertical joints, but call for Z-flashing at

     
  • Are Bubble-Wrap R-Value Claims Accurate?

    Q. Are Bubble-Wrap R-Value Claims Accurate? Am I the only one confused by the claims of manufacturers of foil-covered bubble wrap and foil-covered flexible thin plastic foam? Apparently, if one is to believe the advertising, a 3/8-inch-thick roll of foil-

     
  • Double Vapor Barriers

    Q: While building a new home in upstate New York, we installed R-15 kraft-faced insulation in the walls, but the local building inspector then made us install 4-mil poly over the kraft paper facing. We've been told by other builders and inspectors that this is not a good practice. Is this double...

     
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    Products

    Panels; metal roofing; insulation

     
 
 
 
 
JLC Field Guide to Decking