How to Make a Good High-MERV Filter Even Better
I hate it when I don't see ahead of time what seems obvious afterward. I've assembled a lot of things in my life, including a house and two VW engines, and I can't tell you how many times I've gotten…
The Energy Vanguard Blog
Understanding Manual J Occupant Loads
People complicate things. If, say, you want to sell a motorcycle, you place an ad and interested potential buyers come check it out, maybe take it for a little ride, and then one of them buys it. But every once…
10 Consequences of Keeping Your Home Really Cold in Summer
I briefly worked at a dry cleaning shop in St. Louis a long time ago. It was December, and we had a bout of super cold weather one week. The temperature dropped to 0° F at night and got up…
Ten Years of Building Science Summer Camp
Ten years ago today, I published one of the most significant articles I've written here in the Energy Vanguard Blog. Titled I Don't Need No Stinkin' Building Science Summer Camp!, this article got me invited to that invitation-only event where…
Why Do Air Conditioning Vents Sweat?
Back in the summer of 2005, I got a call to figure out a moisture problem in a new house. The homeowners took me into the master suite, where the first thing to catch my eye was the towel folded…
Humidity, Health, and the Sterling Chart
The classic chart demonstrating the importance of keeping to the middle of the relative humidity spectrum has been shown to countless attendees of classes, conference presentations, and webinars on building science, indoor air quality, moisture problems, and health. I can't…
My Duct Systems on Low-Static Mini-Split Air Handlers
I've written about the load calculation and equipment selection process I went through for the new Mitsubishi* ducted mini-split heat pump in my house. Now let's take a look at the design and performance of the duct systems for the…
My Low Pressure-Drop, MERV-13 Filters
Filtration is on the minds of a lot of people lately. Because of the coronavirus pandemic, most of us would prefer not to breathe in air that contains any hint of the SARS-COV-2 virus that's been spreading the illness known…
My Undersized Ducted Mini-Split Heat Pump
Last year my wife and I bought a 1961 ranch-style house, and I've been having a lot of fun fixing it up. I wrote about the problem with the spray foam in the attic not covering the top plates and…
Understanding Filter Ratings: MERV, FPR, and MPR
As much as I've written about filters and filtration in this blog, I have to confess there's one aspect of filter efficiency I've resisted learning about. Every article I've written that mentions filter efficiency talks about only one rating scale: …