Save energy, save money: insulate

As I’ve mentioned before, heating – including both space heating and water heating – accounts for up to two-thirds of the energy use in the average Western Washington home.

If you’re trying to reduce your heating bills, start by looking at the possibility of updating your building envelope – all of the surfaces of your home, plus its insulation. Our home in Shelter Bay was insulated well in 1978, when it was built. However, today’s insulation codes, depending on the type of space (e.g., walls vs. attic), require about two to four times as much insulation. It’s fairly easy to upgrade insulation. Attic insulation can just be replaced with new materials. Wall insulation may require some additional work, but expandable foam insulation – an innovation that wasn’t available in 1978 – makes that job much easier.

Insulation is far less effective if you have air leaks of any kind, e.g., through cracked windows or doors that aren’t well-sealed, or even woodpecker holes. You can find leaks with an infrared camera. Instructions are readily available on YouTube. Use the search term “use infrared camera to look for air leaks.” Leaks are usually easily sealed with expandable foam insulation.

Changing your windows may be important too, especially if you have old single-pane windows; windows with aluminum frames; or multi-pane windows that are experiencing condensation on the interior side of any pane. New windows have ­ultra-thin, transparent coatings that help to keep heat in the house in winter months. (You can also buy versions that keep heat out of the house in summer months, but the winter months are more relevant here.)

Glass is thermally conductive, so heat travels through it easily. Single-pane windows are long obsolete. From an insulation standpoint, they’re almost as bad as an open window. Still air is a very good thermal insulator, so today’s windows have two or three panes separated by air.

Aluminum is also very thermally conductive. Today’s window frames are made from less conductive plastics and have air channels inside them, again taking advantage of the very inexpensive insulation properties of still air.

Finally, if you have condensation inside a supposedly sealed window, it isn’t sealed any more.

Shortly after Jenelle and I moved into our house in Shelter Bay, which was built in 1978, we upgraded our insulation to the current code and replaced our aluminum-framed windows with modern coated windows with plastic frames. The total cost for both upgrades was about $12,000. We also replaced the old electric furnace and resistance heating strips with a new heat pump. Our December electric bill has fallen from $750 to $250.

Federal energy efficiency tax credits and PSE energy conservation incentives helped pay for all three projects. Both the tax credits and the conservation incentives have easy application processes. For the tax credits, you just file the energy efficiency tax credit form with your 1040. For the PSE credits, apply to PSE via their website before starting work.

Water heaters have also improved significantly over the last 40 years, through the use of better insulation on both the tanks and the pipes. Some new models even use heat pumps, which can be two to three times as efficient as a conventional electric resistance heater. If your water heater is more than 10 years old, it’s probably worth replacing.