Should You Turn Your Heat Down When You're Not Home?

By: Chris Opfer  | 
woman leaving house
Do you save more money by turning down your heat when you leave home or by keeping it at the same temperature? Dirima/iStock/Thinkstock

What's worse than freezing your keister off on when Old Man Winter blows through town? Freezing in your own home. The trouble is, those pesky heating costs can really pile up. The largest expense in the average U.S. home is space heating, which accounts for about 45 percent of annual energy bills [source: Department of Energy]. Households that use natural gas spend about $950 a year on heating costs, while the price tag for those who rely on oil to keep their houses and apartments cozy is a whopping $2,115 annually [source: National Energy Assistance Directors Association]. That's not to mention the money that goes toward keeping a home – and those who live in it – cool when the weather turns warm, an effort that reflects roughly half of a household's energy costs during summer months.

Whether its layering on multiple pairs of sweatpants to fight off the chills or stripping down to your skivvies and opening every window in the joint to beat the heat, many people go to all kinds of lengths in order to save a little dough on their energy bills. That includes turning the heat down – perhaps even off completely -- when they're not at home.


But is this the right approach? Sure, it seems kind of strange to heat a home that no one's using and, of course, adjusting the thermostat downward saves money that would otherwise go to keeping the place at a reasonable temperature during these times. But some argue that those savings are more than offset by the cost of reheating the domicile when you get back home.

So what's a cost-conscious home dweller to do?


Drop the Needle, Save Cash

You've probably read or heard that a heating unit has to work harder to warm up a cold house than to maintain the temperature in an already cozy space. This is what the U.S. Department of Energy likes to call a "common misconception."

The truth is that it requires more energy to keep the house at its normal temperature than to heat it back to that temperature after dialing the thermostat down. Heat naturally moves to places where it's cold. So if your heat is up, it is constantly moving from the inside of your house to the outside, even if your house is well-insulated. A home loses energy more slowly once the temperature inside drops below normal levels. The longer the house remains cold, the more energy it saves compared to the energy lost that comes when the heater is humming along at its normal temperature [sources: Department of Energy, Sierra Club].


The same principle holds for home cooling purposes. The higher the air temperature rises above typical levels inside the house, the slower it loses energy. The slower it loses energy, the easier it is to re-cool the home when you get out of bed or return at night [source: Department of Energy].

That doesn't mean you should shut the furnace or air conditioning unit off entirely before you leave your house, especially if you're going to be gone for a while. When a house gets too cold, it puts the pipes at danger of freezing. When it gets too hot, condensed air can do a number on wood floors, cabinets and other surfaces [source: Martin].

If you're looking for a sweet spot, in winter keep the thermostat at about 68 degrees F (20 degrees C) when you're home and drop it down to about 55 degrees (13 degrees C) before you go out or go to bed. The same goes for cooling costs: Keep the house warmer than normal when you're not home and try to leave the thermostat at around 78 degrees F (26 degrees C) otherwise [sources: Department of Energy, Sierra Club].

According to the U.S. Department of Energy, a family that sets back its thermostat by about 10 to 15 degrees for eight hours a day while sleeping or out of the house can save 5 to 15 percent a year on home heating costs.


Other Ways to Save Energy

 programmable thermostat
Using a programmable thermostat can save you 10 percent off heating and cooling bills annually. tab1962/iStock/Thinkstock

Working the thermostat is an important first step to maximizing energy efficiency, but there are also a number of other things you can do to cut down on home heating and cooling costs without sacrificing too much comfort.

First, make changing temperatures easier by investing in a programmable thermostat. This technology allows users to schedule heating levels to automatically rise when they wake up or come home at the end of the day. Most of the devices also let users to store and repeat daily settings and can be changed manually when necessary [source: Department of Energy].


Programmable thermostats are less helpful – and may actually prove more costly – for people who rely on heat pumps to warm their homes. In heating mode, the pumps are most efficient when running at a constant, moderate level and scheduling various temperature changes can cancel out any potential savings [source: Department of Energy].

Next, make sure your heating and cooling systems are running efficiently to ensure that you're not wasting energy on them. That means cleaning filters and replacing them regularly, removing dirt and addressing corrosion on HVAC units. It also means checking that vents and radiators are not obstructed and that air ducts and heating pipes are properly sealed [source: Department of Energy].


Turn Heat Down FAQ

Does turning down the thermostat save money?
Yes, homeowners can save money on their energy and heating bills by turning the thermostat down. You can save almost 15 percent of your total heating bill by lowering your heat by seven degrees overnight (or for any other eight hour period).
How do you turn your heat down?
Turning the heat down is easy. All you have to do is locate the thermostat in your house and make the necessary adjustments. It may depend on your heating system, but most have up and down arrow buttons that increase or decrease the desired temperature.
What temperature should you keep your house in the spring?
To some degree, it depends on the climate where you live. However, a good rule of thumb is to 68 degrees in winter and 78 degrees in summer.
Is it bad to turn the thermostat up and down?
No, it’s a common misconception that it’s harder on a furnace (and the resulting bill) to warm up a cold house than to maintain an already-warm space. It’s perfectly fine to adjust your thermostat on a regular basis. It requires more energy to maintain a temperature than it does to reduce the temperature for a period and then turn it back up.

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Author's Note: Should you turn your heat down when you're not home?

When you reside below ground, as I did until recently in the "English basement" apartment of an urban row house, it can be difficult to keep the joint warm. The task is made even more challenging when large swaths of the nation are enveloped in the unforgiving blanket of frigidity known by meteorologists and Arctic residents as a "polar vortex." By challenging, I mean it required me to run heating units on full blast all day, even when I wasn't at home. I'm happy to report that I'm now firmly four floors above ground.

Related Articles

  • CBS News. "Will colder temperatures help you lose weight?" Jan. 23, 2014. (Feb. 23, 2014)
  • Martin, Brett. "7 Things to Do Before You Leave for Vacation." Popular Mechanics. (Feb. 23, 2014)
  • National Energy Assistance Directors Association. "Home Heating Costs Reach Highest Level in More than 10 Years" (Dec. 22, 2022).
  • Sierra Club. "Turn the Heat Down, or Leave It on When Gone? What's Best, Mr. Green Santa?" Dec. 27, 2010. (Feb. 23, 2014)
  • U.S. Department of Energy. "Energy Saver 101." Dec. 16, 2013. (Feb. 24, 2014)
  • U.S. Department of Energy. "Thermostats." Nov. 26, 2013. (Feb. 24, 2014)