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…
There's a ton of new construction and remodeling going on in Atlanta. On a lot near where I live, a developer tore down the old house and is building two new ones. This weekend, I took the opportunity to check…
I've been working on my presentation for the 10th anniversary of the North American Passive House Conference. It's on the global warming impact of insulation, a followup to my latest article about Alex Wilson's work on that subject. One of…
Air conditioner sizing rules of thumb must die. That's what I wrote in my last article. The most common rule of thumb is to use 500 square feet per ton to determine the size of air conditioner needhttps://www.energyvanguard.com/blog/more-on-air-conditioner-sizing-rules-of-thumbed. Or 400…
We design a lot of heating and air conditioning systems at Energy Vanguard. When I talk to potential clients, a lot of them tell me their contractor wants to size their air conditioner using a rule of thumb. The rule…
Remember my bathroom remodeling project? I took the liberty of gutting our outdated, decaying bathroom while my wife was out of town in April. I found some interesting air leakage pathways when I opened the walls. I fixed that. I found…
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…
I've seen some crazy things done to homes. It's usually someone's attempt to make things better. Sometimes that someone is a homeowner or other occupant. Sometimes it's a contractor. But it always seems to be a solution to a problem…
Ah, ventilation. One of the easier topics in building science. Everyone agrees: We need airtight houses. Airtight houses need mechanical ventilation. Build tight. Ventilate right. No problem! We're all on board. There's nothing to disagree about. Right? Ah, ventilation. One…
I've got a record of 14 blower door tests on my condo. Many of them were during home energy rater classes, as we'd bring them here for the confirmed rating they needed to complete. The early ones were horrible! But…