At my first Building Science Summer Camp in 2011, David Hill (in the photo below) gave a great presentation on some of the big problems with duct systems. (In case you weren’t reading this blog back then, I got myself…
WARNING: This article contains graphic and disturbing images of a duct system that may upset anyone sensitive to low-quality air distribution. If you've ever experienced nausea, fainting spells, or outbursts of anger upon being exposed to such stimuli, I urge…
There's a problem with relative humidity. I hear it a lot when I talk to people about moisture problems. A client with high humidity in his home recently told me he didn't understand how it could be more humid inside…
If you've ever wanted to learn how to cook with the sun, the 2015 Solar Cooking Festival in Sacramento was the place to be. This is the second year of the event, hosted by Solar Cookers International. They had quite…
I got a question this weekend that's often asked—and, I'm sure, wondered about—by homeowners: "Will my household AC system run more efficiently (perhaps cycle on/off fewer times, or the compressor won't have to run as long when it cycles on)…
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…
Wet bulb temperature tells you how easy it is for water to evaporate. Sounds simple enough, right? Today I'll give you a couple of examples to see how well you really understand that simple statement. First, early last month my…
Energy codes have all kinds of requirements. You have to have certain R-values in walls, floors, and ceilings. Your windows have to have the right U-values and solar heat gain coefficients. The infiltration rate and duct leakage have to be…
Who among us doesn't love spending time in crawl spaces and attics? I've certainly done my time there. A lot of my friends hang out there, too. I found out in an email from the Building Performance Institute (BPI), however,…
As long as we're exploring the wonderful world of water, we ought to show some of the cool stuff it does. In my article Introduction to the Physics of Water in Porous Materials, I described hydrophilic, hydrophobic, and hygroscopic materials.…