If your heating system runs constantly or your home is drafty in the winter or hot in the summer, you might have a weatherization problem. Insulating your home and replacing your windows is a worthy consideration. It's an investment upfront, but it's a proven long-term strategy for lowering your heating and cooling costs while improving your home's comfort.
Washington state energy code sets minimum levels of insulation for new homes and remodeled homes. The insulation requirements are based on the cost-effective savings for the region over the life of the home with a specified level of insulation. And those codes have changed over time.
Exactly how much insulation your home needs depends on the cost of the fuel you use to heat it. An economic rule-of-thumb is — the less you pay for heating fuel, the less insulation you need to install.
Homes built during the 1960s and 1970s had little insulation. During those decades, heating fuel was cheap and neither builders nor homeowners could justify investing in insulation. But times have changed. Heating and cooling costs have increased and continue to rise. So today, builders and homeowners alike believe investing in insulation for the long term pays off.
Today, new homes must have R-38 insulation in ceilings (15 to 18 inches of blown-in insulation) and R-30 insulation in the crawl space or basement under floors (a 10-inch thickness). Some new homes are also built to the Energy Star standard, making them more energy efficient all around.
Depending on the construction of your home, its age and how much weatherproofing work previous owners have done, the amount of insulation you need to reach these R-ratings will vary. By measuring what's installed in your attic and under the floor or in the basement ceiling, you may find you simply need to add enough to bring your home up to an R-rating that makes sense for your home's heating system.
But will it pay to up your R-rating? Maybe not. For example, if you go from no floor insulation to R-19, you gain 90 percent improvement. But you'll gain just a 36 percent improvement upgrading an existing R-19 insulation to an R-30 rating. Depending on your heating costs, it may not pay. And there might be other ways to tighten up your home so you lose less heat.
Even if your home is well-insulated, your windows still might let heat out. Approximately one-third of the heat loss from a home flies out its windows. So replacing single-pane windows with double- or triple-pane ones that meet Energy Star specifications can be smart. For tax credits and rebates, you must install a window with a U-factor of 0.30 or lower and an SHGC of 0.30 or lower. U-factor measures how much heat escapes and is more important for our cooler winter climate. The SHGC measures how much sunshine heat transfers through the window and is more important for warmer climates.
Weighing the options
Weighing the options can be overwhelming, but Clark Public Utilities has a team of energy counselors available to answer your questions or even come visit your home to see what weatherization measures might make the most sense. You can call the Energy Counselor of the Day line at 360-992-3355 during business hours to get advice or make an in-home energy review appointment.
The utility offers incentives for various weatherization projects, and loans of up to $15,000 at 5.25 percent interest for insulation and windows installed in electrically heated homes by an approved contractor. If you're looking to insulate your home or add new windows, check out the Clark Public Utilities online brochure with details about the incentives and loans or request a copy of utility brochures online. You can find lists of approved contractors on the utility's website, too. All the utility's weatherization projects that carry incentives are checked by an energy counselor.
If you heat with natural gas, you can receive energy efficiency rebates and incentives through Energy Trust of Oregon. Visit www.energytrust.org/washington for more information.Energy Adviser is written by Clark Public Utilities. Send questions to email@example.com or to Energy Adviser, c/o Clark Public Utilities, P.O. Box 8900, Vancouver, WA 98668.