Tips for keeping your home warm when the temperature drops

Ask the Expert
Vacuum your radiators during the heating season to boost their efficiency. Adobe Stock

A good chunk of winter is behind us, but the heating season still has at least a couple of months to go. Whether you own or rent your home, there’s a lot you can do to lower your heating costs and maximize your comfort.

I was a licensed builder and home inspector in Greater Boston for many years. Richard Trethewey has been “This Old House’s” plumbing and heating expert since 1979. Since he literally wrote the book on home heating and cooling, I reached out to him for his insights. Trethewey said homeowners looking to make their homes more comfortable should start at the top.

“People know that heat rises,” Trethewey said. “Forget about the walls for a minute. The first thing to do is insulate the attic/crawl space floor.”

Massachusetts homeowners can get a free energy audit from Mass Save that will identify energy losses and inefficiencies in their homes. Mass Save also offers free low-energy light bulbs and insulation installation subsidized by the utility companies. It can save homeowners a lot of money.

“The other major culprit is infiltration [cold air leaking in from outside],” Trethewey said. “Heat always goes toward cold. If my skin temperature is 74 degrees and I stand next to a drafty window in the winter, the heat will leave me and go toward the window, leaving me feeling cold.”

If  your apartment windows rattle in the wind, Trethewey said, “Don’t overlook those weatherstripping kits with clear shrink wrap. They work. They keep air from moving in and out of the building. Heavy, thermal drapes work well, too.”

If you own your home, repairing and recaulking those drafty windows and storm windows can be less expensive and just as effective as replacing them, Trethewey said. Airtight windows are essential to comfort as temperatures fall and the winds pick up.

It may sound simple, but his next tip can save you a bundle and keep you from bundling up: Make sure all the windows in your home are closed and latched. Top sashes tend to slide downward over time if they’re not locked, letting cold air into your home.

Anyone who uses a smartphone should have a an Internet-connected smart thermostat in their home, Trethewey said. They are far superior to the old programmable thermostats of the 1980s. They learn your schedule and heat the house accordingly. They also allow you to turn the thermostat up or down from almost anywhere with WiFi or a decent cell signal.

If your heating system is old, replacing it is an expensive proposition. New equipment uses much less energy, so if you plan to live in your house for a long time, it may be worthwhile to upgrade your system, as fuel prices are generally expected to rise over the long term.

When shopping for contractors to replace your system, insist that they perform a heat-loss analysis on your home to determine the precise size of the system it needs. Many heating systems are substantially oversized, Trethewey said. These owners bought too much equipment, that equipment will fail too soon, and the operating costs will be too high, he said.

“If it’s sized correctly, your heating system should be running almost continuously on the coldest days of the year,” Trethewey said. “If someone had $10,000, they could put it in a passbook savings account and maybe lose money, they could put it into the stock market and make maybe six or seven percent annually, or they could put it into a new heating system and it would reduce your heating cost every year —tax free. It’s one of the best money plays a homeowner can make.”

Every mechanical device needs regular maintenance, especially your heating system. Trethewey recommends having it tuned up annually to minimize heating bills and make it last longer. Cleaning and servicing your heating system should cost under $200 a year and will save you much more than that.

“There’s no appliance anywhere that the public expects more longevity out of than the heating system,” Trethewey said.

If your heat comes out of vents in the floor or ceiling, there is an air filter in the furnace that must be replaced a few times a year. Very few of these filters are replaced often enough, and that raises your energy costs significantly, he said. Replacing that dirty filter with a new pleated, high-efficiency return one every 6 to 8 weeks during the heating season will keep the air in your house cleaner, lower your heating bills, and extend the life of your furnace, he said.

If your house is heated via radiators, vacuum them once or twice a season. While you’ve got the vacuum out, roll it on over to your fridge and suck up the dust covering the coils on the bottom or back of it. That will lower your electric bill and keep the kitchen a little warmer, he said.

Most water heaters are also big energy wasters. Trethewey said that the thermostats in many water heaters are set too high and that’s worse than wasteful; it can be dangerous. And remember: A typical American water heater is designed to keep 40 gallons of hot at all times, for the few times a day it is actually used. Turning them down makes them safer, more efficient, and last longer

“You don’t want to deliver water any hotter than 120 degrees.” Trethewey said. “It’s not uncommon to find them turned up to 140 degrees or higher.”

Trethewey suggests turning water heaters down to no more than 120 degrees and adjusting the mixing valve in your shower so the water coming out of the head is no hotter than 113 degrees. There are videos on the This Old House website and on YouTube that can show even the least handy people how to do this.

If you live in an apartment, your landlord is required by state law to provide a heating system than can heat your unit to 68 degrees during the day and 64 degrees at night from Sept. 15 to June 15. If your apartment can’t meet that Sanitary Code standard, contact your local board of health or building inspector.

Anyone who is financially struggling to heat their home can try the state’s Low Income Home Energy Assistance Program for help.

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