The blower door fan sounds like our shop vac's bigger, angrier cousin, so Moose spent our home energy assessment in Gary's backyard, eating a biscuit he wasn't supposed to have.
The assessment was last Wednesday, September 24, four days after we got back from the honeymoon. It was a Consumers Energy in-home assessment, at no charge to us at the time. I took the afternoon off for it, which my manager allowed because I'd been back for a full two days.
How it worked
The assessor spent about three hours at the Cape. He started with a walk-through and questions: age of the furnace and water heater, how cold the upstairs gets, where we feel drafts. Then he went everywhere I usually avoid. He looked into the top attic through the hatch in the bonus room ceiling, crawled into both knee-wall spaces off the upstairs bedroom and spent a long time in the basement with a flashlight.
Before the big test, he did safety checks on the furnace and water heater, since both vent into the chimney. He checked that they were drafting properly and measured carbon monoxide in the flue. Both passed. He still flagged both as aging: the furnace is a 1998 Carrier and the water heater is from 2009.
Then the main event. He fit a red nylon panel with a big fan in it into the front door frame, closed every window and ran the fan to pull air out of the house until it held a set pressure. The result is how many cubic feet of air per minute the fan has to move to hold that pressure, which tells you how much the house leaks. Ours was 2,950 CFM50. He said, politely, that this was leaky for a house our size. I said that matched my ankles last winter.
While the fan ran, he walked around with a thermal camera and a smoke pencil and showed me where air was coming in. Watching cold streaks bloom on his screen made me want a thermal camera of my own, which is a thought I'm trying to talk myself out of.
The list
The report came by email the next day. The main findings:
- Top attic insulation around R-11. A few inches of old fiberglass, flattened in places.
- Knee walls partly bare, and the floors of the knee-wall spaces patchy.
- The bathroom fan was venting into the knee-wall attic. The duct just ended in the space, and the insulation around it was damp.
- Bare rim joists all the way around the basement.
- Air leaks at the attic hatch, both knee-wall doors, outlets on exterior walls, the front door weatherstrip and the plumbing holes in the basement ceiling.
- Furnace and water heater working and safe, but old enough to plan for.
Tessa read it at the kitchen counter that night and summed it up: "So the house is basically a screen door with siding."
What we're doing ourselves, and what we're hiring out
I went through the list with the house sheet open and sorted every item into three groups.
Me, soon. The bath fan was the most urgent, because it was putting moisture where it can rot wood. I rerouted it last night, and that gets its own post. The rim joists are this weekend, with foam board and canned foam. Weatherstripping and outlet gaskets are a job for a cold evening in early November, when drafts are easy to find. A programmable thermostat is on the list too.
Hired out. Air sealing and insulation in the top attic and knee walls. I could probably rent a machine and blow cellulose myself, but the air sealing is the tricky part, the knee-wall spaces are miserable to work in, and Consumers' rebate requires a contractor from their participating list. I'm collecting three quotes now. We've also read about a federal tax credit for insulation materials, and we'll ask a tax preparer how it applies before we count on any of it.
Not now. The furnace and water heater. Both work, both passed the safety checks, and replacing them is a big decision I'd rather make on our own schedule. They're in the house sheet with a column for when we start setting money aside.
After the insulation crew finishes, there's a second blower door test to see how much tighter the house got. There's already a cell in the house sheet waiting for that number, and I've caught myself guessing at it more than once.
