Wednesday, August 16, 2017

The Joy of Flex

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A recap of my Building Science Summer Camp presentation
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I recently spoke at the Westford Symposium on Building Science. You may know it better as Building Science Summer Camp, since that's what everyone calls it. I'll fill you in on what you missed if you weren't there.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/joy-flex

Wednesday, August 9, 2017

Raised-Heel Trusses Make Better Enclosures

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This is another easy advanced framing technique for every home with roof trusses
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A comfortable, energy-efficient home begins with a good building enclosure. That means control layers. You've got to control the flows of moisture, air, and heat.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/raised-heel-trusses-make-better-enclosures

Wednesday, July 26, 2017

Using Total Effective Length in Duct Design

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For air flow purposes, a duct system is often much longer than it appears
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Today I’m going to explain an important concept in one of the most popular ways of doing duct design. I’ve been writing a series on duct design over at my blog and began with a look at the basic physics of air moving through ducts. The short version is that friction and turbulence in ducts results in pressure drops. Then in part 2 I covered available static pressure. The blower gives us a pressure rise.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/using-total-effective-length-duct-design

Thursday, July 20, 2017

Pete’s Puzzle: Mold on Painted Clapboards is Food for Thought

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There is mold on the factory-primed, latex top-coated wood clapboards on the south but not the north side of our house
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Whenever my wife starts a conversation with, “OK, Mr. Building Scientist,” I know I am in some kind of trouble. That proved to be the case one day when we were out hanging laundry on the south side of our house.

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from Building Science http://www.greenbuildingadvisor.com/blogs/dept/building-science/pete-s-puzzle-mold-painted-clapboards-food-thought

Wednesday, July 12, 2017

62 Things We Should Ban to Improve Home Building

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Let’s clean this mess up once and for all
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Let's face it. The state of home building isn't good. Yes, we have building science and energy codes and green building programs out the wazoo. We have cool new products and home energy raters and even Joe Lstiburek. Despite all this, we still have wild ductopuses, holey air barriers, and insipid insulation installations.

And I've finally lost my patience. I think the only way to improve the state of home building in America is to ban these things.

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/62-things-we-should-ban-improve-home-building

Wednesday, June 28, 2017

Air Sealing the Ceiling Joists in an Attached Garage

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A little forethought makes it a lot easier
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The I-joists in the lead photo here run across the top of the wall between the dining room and the attached garage in this home under construction in the Atlanta area. In the old days, before anyone worried about air moving through those joist cavities, the builder didn’t bother to do anything beyond securing the joists.

You can see here, though, that the builder of this home knows a thing or two about air sealing because they've put blocking between the joists. But what do they do next?

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from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/air-sealing-ceiling-joists-attached-garage

Thursday, June 22, 2017

Combining Sheathing With a WRB and Air Barrier

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How well do Zip and ForceField sheathing integrate a structural panel with bulk water and air management?
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Full Disclosure: First, there are a lot of different ways to get continuous air and water control layers on the exterior of a building enclosure. You can use housewrap, taped-and-sealed rigid foam insulation, liquid-applied membrane, or either the Huber Zip or Georgia-Pacific ForceField system. Each approach has strengths and weaknesses.

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from Building Science http://www.greenbuildingadvisor.com/blogs/dept/building-science/combining-sheathing-wrb-and-air-barrier