When you get into the world of building science, it's inevitable that you'll hear about the study that proved fiberglass insulation loses half its R-value because of convection within the insulation. Or it could be you're a homeowner who's been…
Welcome to another January, this time in the year 2019. The month, of course, is named after the Roman god Janus, who has two faces, one looking backward, one forward. Because, you know, to really know where you're going, you…
Happy birthday to Willis Carrier! He invented modern air conditioning and changed the world. In his quest for a device to control humidity in the Sackett-Wilhelms Lithographing & Publishing Company in Brooklyn, New York, he invented a device that changed…
What is a hair's breadth? A strand of the finest human hair is about 20 micrometers (also called microns) in diameter. Take a piece and slice it in half. Then take one of those halves and slice it in half…
KERKLUNK!I instantly spring up in my bed at the loud noise. "What the heck was that?!" I don't know but it seemed to have come out of the heating vent on the wall above my dresser.I'd been lying quietly in bed…
As we continue our study of indoor air quality and filtration, we now come back to duct design. Today's lesson is on an interesting bit of physics that applies to anything that flows. It could be heat or particles or…
Indoor air quality (IAQ) researchers have established that little bitty invisible pieces of stuff that float around in the air are bad for human health. Of course, being scientists, they don't call it little bitty invisible pieces of stuff. They…
That face above is of a physician, alchemist, and astrologer named Philippus Aureolus Theophrastus Bombastus von Hohenheim. He is deemed the father of toxicology and is better known by the name Paracelsus. I begin this article with him because Dr.…
Last year I wrote some articles on duct design and one of the topics I covered was this thing called friction rate. At the end of that article, I discussed "How to think about friction rate." It confuses a lot…
I've posted a lot of crazy duct system photos here in this blog. Remember "Release the Kraken!"? How about "Two Jellyfish Mating"? And about three years ago I found one that instantly became my new favorite duct disaster. But those…