Kris and I own an old house. During the winter, the cold air seeps in through cracks in the windows and beneath gaps in the doors. We’ve done what we can to keep our heating costs low, and we make a handful of additional improvements every year, but I still feel like we’re living in a “drafty old barn” (to quote George Bailey).

Sometimes all of our hard work goes for naught. For example, we recently hired contractors to repair some rotten siding. As they were working, they discovered this:

This heating duct leads to an upstairs bedroom. Note how the duct itself has pulled away from the funnel-shaped bit beneath the floor register. There’s a two-inch gap where the hot air was escaping. For the past several months, we have essentially been heating our basement. Kris and I could have gone for years without noticing this; to see the gap, we would have to look straight up while walking down the steep basement stairs.

My heart sank when the contractor pointed out the problem. I wondered how much this had cost us.

You’ll recall that I’ve automated some of my bill payments, including our natural gas. In theory, I’m supposed to check the statements every month. In reality, I haven’t done so since I switched to automatic payments last spring. Because of this, I never knew there was a problem. Checking the statements now, however, I can see that we’ve used a lot more energy in 2009 than we did in 2008.

  • January — 2008: 98.3 Therms ($124.23), 2009: 144.7 Therms ($213.07)
  • February — 2008: 120.5 Therms ($156.95), 2009: 146.6 Therms ($208.23)
  • March — 2008: 104.5 Therms ($133.71), 2009: 128.8 Therms ($181.36)

During the first three months of 2008, we used 323.3 Therms, which cost us $414.89 (or about $1.28 per Therm). During the first three months of this year, we used 420.1 Therms, which cost us $602.63 (or about $1.43 per Therm). We used an additional 96.8 Therms this year, an an increase of 30%. Wow. Using that cost of $1.43 per Therm, that’s an additional $138.42 we’ve paid for heat.

Here’s a screencap that shows a graph of our energy usage:

There’s no way to tell exactly how much of our increased heating bill is due to the gap in the ductwork, but my guess would be “much of it”. (I guess we’ll find out next winter.) It’s true that I’ve been working from home this year, but I worked from home in March 2008, too. And I don’t mess with the thermostat. When I’m cold, I don’t turn up the heat. I bundle up.

Once again, I’m encouraging you to learn from my mistakes. Make a periodic check of your heating and cooling system to be sure everything’s functional. And if you’ve set up automatic payments, be sure to check your statements on a regular basis.