Our Heating Bill Doubled and Every Window Tested Fine

Our January heating bill landed at $340. The month before? $180.

We hadn’t changed the thermostat. We hadn’t left windows open. The weather was cold, sure, but not twice as cold.

Something in the house was bleeding heat, and we had no idea where.

I started with the obvious suspects. Every window got the hand test—palm pressed flat against the glass, then along the frame. Nothing. I ran a lit candle along the baseboards in every room, watching for the flame to flicker. It didn’t.

My husband checked the weatherstripping on both exterior doors. Totally intact. We even went down to the basement and inspected around the foundation where the rim joist meets the sill plate, because we’d read that’s a common culprit.

Still nothing.

The furnace was running constantly. We could hear it kicking on every twenty minutes, laboring to keep the house at 68°F. Somewhere, all that expensive heated air was escaping.

We just couldn’t figure out where.

Then my friend Sarah came over, took one look at our ceiling, and asked a question we hadn’t even considered.