The past 2.5 years of the COVID pandemic have put a big spotlight on indoor air quality and the spread of infectious disease. I've been writing about various aspects of indoor air quality since I started this blog in 2010,…
What?! Building enclosures and mechanical systems are both important in homes. The building enclosure is where the control layers are, those parts of the building that control the flows of heat, air, and moisture. The mechanical systems provide heating, cooling,…
You may have found yourself needing to understand building science for one of a thousand different reasons. Perhaps you've bought a house and want to make sure it's comfortable, healthy, and efficient. Maybe you're an architect with a new client…
I've written a lot of articles about ducts here, but I haven't yet addressed today's topic: common problems with ducts and how to fix them. This one is for homeowners or renters who want to save money and be more…
Humidity control is becoming a bigger deal than it used to be. As Joseph Lstiburek, PhD, PE said to me one time, "the gap between stupid and hurt is narrowing." Building codes and best practices are getting better, which is…
In my last post, I told you about the plumbing work I did to begin the retrofit of my hot water distribution system. I'm bypassing the original too-long, too-big copper pipes with shorter, smaller runs of PEX tubing. My goal…
Did you know that some plumbers stuff a wad of white bread (sans crust) into a pipe before they solder it? That's one of the things I learned during my weekend plumbing adventure. More about that later, though. The purpose…
I love the US energy flow charts published by the Lawrence Livermore National Lab each year. The chart for 2021 came out in April, and you can see it in its full glory above. (Right click to download the full…
This past week I learned the truth about another one of many building science lies. It's the first one in my list here. Having my eyes opened to that lie made think of some of the other ones out there. …
You may recall that I wrote about my undersized mini-split heat pump a couple of years ago. It's undersized compared to both the heating and cooling loads, as you can see in the table below. I'll discuss the heating performance…