Energy Vanguard Blog

Are You Confusing Insulation with Air Barriers?

Posted by Allison Bailes on Tue, Nov 24, 2015

I read a lot of stuff online about insulation and air barriers and other building science topics. I see a fair amount of people bashing certain products or materials. Sometimes it's because they sell a competing product. Sometimes they just don't like a product. Take fiberglass insulation, for example. What thoughts just went through your head?

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Tags: insulation, air leakage

Accidental Dehumidification - A Preventable Mess

Posted by Allison Bailes on Fri, Nov 20, 2015

"Oops! The house just had an accident. Whose turn is it to clean it up?" Yep. We're entering the season of accidental dehumidification. If you've got windows that start collecting water, like the one shown below, you're a victim of accidental dehumidification. It's not something you want in a building.

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Tags: insulation, air leakage, indoor air quality, water, moisture problems

10 Essential Steps to Building a Pretty Good House

Posted by Allison Bailes on Mon, Aug 24, 2015

My friends up in Maine came up with the concept of the Pretty Good House a few years ago, and I love the idea! Not everyone can or wants to build a LEED Platinum, Living Building Challenge, Passive House. But a lot of architects, builders, and homebuyers would like to design, build, and live in houses that are better than the barely-legal, code-minimum houses that populate the market. The Pretty Good House, then, is the way to go.

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Tags: design, heating & cooling distribution, insulation, air leakage, windows, moisture problems, ventilation, heating & cooling

The Wonderful, Blunderful World of Construction

Posted by Allison Bailes on Fri, Jul 10, 2015

Jeffrey was driving through Atlanta the other day and saw a new building under construction that forced him to slam on the brakes. He got his camera out and took the photo below. Can you see why he was so excited?

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Tags: building enclosure, insulation

Joe Lstiburek's Ideal Double-Stud Wall Design

Posted by Allison Bailes on Wed, Apr 29, 2015

Joe Lstiburek called me last week to set the record straight. I had written an article about a study of moisture in double-stud walls in a Massachusetts home, and his company, Building Science Corporation (BSC), had done the research as part of the Building America program. They found elevated moisture content in the cold, exterior sheathing, and Joe wanted to make sure everyone knew, "I would never build that wall because I consider it too risky."

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Tags: insulation, moisture problems

Is This the End of the Double-Wall, Cold Sheathing Scare?

Posted by Allison Bailes on Wed, Apr 22, 2015

Insulation is good. More insulation is better (although at some point, more may not be cost effective). It reduces the amount of heat a home loses in winter or gains in summer. You can get there by building thicker walls and putting more insulation in the cavities, or you can put insulation on the outside of the structure, as in the Perfect Wall. The photo below shows thick insulation in the cavities of a home with double-wall construction.

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Tags: insulation, air leakage, moisture problems, ventilation

An Interview with Terry Brennan — a Building Science Pioneer

Posted by Allison Bailes on Wed, Apr 15, 2015

Last week I got a chance to sit down and talk with Terry Brennan in Dallas at the Air Barrier Association of America’s annual conference. He may not be as famous as Joe Lstiburek, but he’s every bit the building science pioneer. Armed with a physics degree, the ASHRAE Handbook of Fundamentals, and a desire to reduce the environmental impact of buildings, he built houses and wrote energy modeling computer programs back in the 1970s and ‘80s. When he finally met Lstiburek in the early ‘80s, he learned not to bet against Joe’s ability to do ridiculous things. Read the transcript of our conversation and find out what that bet was and more.

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Tags: conferences, insulation, air leakage, environment & sustainability

California Mistakes Put Spray Foam Insulation on the "Bad List"

Posted by Allison Bailes on Tue, Mar 31, 2015

Last summer I learned about the state of California's efforts to create more healthful buildings and working conditions. In 2008, they passed the California Green Chemistry Initiative with the intent of reducing state residents' exposure to toxic chemicals. California leads the US in new directions all the time, and green chemistry could be another. Unfortunately, though, they were slow out of the gate and their initial attempts to implement the law don't instill confidence.

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Tags: insulation, spray foam, environment & sustainability, health & safety

Insolation Is Not a Typo for Insulation

Posted by Allison Bailes on Fri, Mar 27, 2015

In 1993 I took a graduate course in solar energy from Professor Yogi Goswami. It was a great course, and one of the projects we had to do was to compile a whole binder full of solar radiation data for Gainesville, Florida. I used an ancient spreadsheet called Lotus 1-2-3 (remember that?) to do all the calculations for various azimuth and elevation angles throughout the year. Another thing I learned in the class was a new word.

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Tags: insulation, solar energy

A Beautiful Solar Home in Utah Nears Net Zero Energy Use

Posted by Allison Bailes on Wed, Mar 18, 2015

I'm writing this on St. Patrick's Day so let me tell you a wee bit about the O'Mearas. Kevin and Svetlana O'Meara live in a beautiful home in Utah that's oh-so-close to being a net zero energy home. After I wrote about how home building is like skiing two years ago, Kevin invited me out to see their home and this year I managed to do so. My wife and I visited them for two days last week and Kevin told me all about the house, including his one major regret.

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Tags: ENERGY STAR, design, heating & cooling distribution, insulation, air leakage, energy code, energy conservation, comfort, windows, environment & sustainability, solar energy, water heating, ventilation, heating & cooling, green building