Why Doesn’t Frost Form in the Carport?
On Saturday morning as I was heading out for a run at the Chattahoochee River, I found my car in the condition you see in the photo above. Let's ignore the reason I was parked half in and half out…
Blog
17 Steps to Better Duct Systems
If a 12 step program is good for helping people deal with addictive behaviors, then a 17 step program ought to be better, right? Or maybe it's just a random number that fits the number of tips that popped into…
The Perfect Weather for a Dehumidifier
That dehumidifier you see in the photo above is in the Energy Vanguard office here in Decatur, Georgia. The compressor doesn't come on often, but this past week I've heard it running quite a bit. Depending on where you're from,…
Is Negative Pressure Causing a Problem in Your Home?
Ever have the smell of your fireplace inside your home? It's not uncommon. Here's a question I got from a reader named Rob last month:We always have a smoke smell from our fireplace, more on some days than others. I…
Busting a Myth About Low-Static Ducted Mini-Splits
I like mini-split heat pumps, especially of the ducted variety. And because I don't like to pay for a lot of excess power, I prefer to use ducted mini-splits with smaller blower motors operating at a low total external static…
Spray Foam Insulation at the Edge – A Forensic Analysis
An attic that's brought inside the building enclosure is a beautiful thing. This is most often done with spray polyurethane foam (SPF) insulation, either open-cell or closed-cell. Here in the southeastern US, open-cell is most often the spray foam of…
The #1 Reason to Have an All-Electric Home
Maybe you've heard the rumblings coming out of the environmental and building science crowd. Maybe not. But it's getting louder lately. The rumbling I'm alluding to is the move to switch from natural gas to electricity as the energy carrier…
The Best Velocity for Moving Air Through Ducts
The first thing to know about the velocity of air moving through ducts is that the slower you get the air moving, the better it is for air flow. That was the main point of my last article. In fact,…
Is Low Velocity Bad for Air Flow in Ducts?
It's obvious that moving air too quickly through ducts can be a problem. Faster air means more turbulence, more resistance, and more noise. But I run into people who think that low velocity also can be a problem in ducts. …
How Often Should You Change the HVAC Filter?
One of the topics I've hammered on for years is the inadequacy of using rules of thumb for sizing air conditioners. The standard one ton of air conditioning capacity for each 400 to 600 square feet of conditioned floor area…