If you want to build a superinsulated, airtight house, you run into some difficulties. How do you deal with the extra thickness of your walls and ceilings when you add all that extra insulation? What's the best way to ensure…
Everyone knows about the impact of burning fossil fuels on global warming. Maybe not everyone believes it, but scientists first started focusing attention on increasing carbon dioxide levels way back in 1827. The impact of insulation on global warming, however,…
At the North American Passive House Conference in Philadelphia in September, I gave a presentation on the global warming impact of insulation, an issue I've been discussing off and on since Alex Wilson wrote his paper on the topic back…
Three weeks ago, I wrote about an attic with spray foam insulation and the interesting humidity pattern we observed in it. We placed data loggers near the ridge and floor of the attic as well as in the living space…
Spray foam insulation can solve problems that other insulation materials can't. One of those problems is moving the building enclosure from the drywall ceiling of a home to the roofline. By doing so, you bring the attic inside the building…
I get asked a lot of questions about spray foam. Do I need an ignition barrier? Should I use open cell or closed cell spray foam? Will open cell spray foam really rot my roof? But the question I get…
When I began remodeling my master bathroom last month, I found the exterior wall ripe for some serious improvement. It had a number of problems, and I was excited to find them. It was worse than I imagined in some…
We talk about R-value all the time. "I've got an R-19 wall," or "Code requires R-38 in my ceiling." But what are those numbers? As it turns out, when we talk about R-value we usually give the R-value of the…
Well, I really stirred things up with my last article on insulation and global warming. My intention was to explain why Alex Wilson's results could be doing a disservice to the green building community. In the end, I was rightly…
A couple of weeks ago I caught up with Anthony Cox at the Air Barrier Association conference in Baltimore. You may know Anthony as the inventor of the House of Pressure, a great model for demonstrating backdrafting, zonal pressure differences,…