What Temperature to Leave a Vacant House
Whether you're winterizing your summer cabin or planning an extended absence over the summer, you might be tempted to turn off your furnace or air conditioning system for the season. Don't do it! Instead, learn what temperature to leave a vacant house for any length of time in any season.
What Temperature to Leave a Vacant House in Winter

Whether you plan to leave for a vacation or for the season, most heating and cooling professionals recommend setting the thermostat to 55 degrees Fahrenheit. This temperature will reduce your heating costs and minimize the risk for hazards such as frozen or burst pipes and flooding. In fact, when leaving a house unoccupied in winter, there are a few additional steps you can take to make sure you don't return in the spring to a disastrous surprise:
- Turn off the water to the whole house.
- Empty the water pipes by letting the water run in an interior bathroom, the kitchen sink, etc., until there isn't even a trickle.
- Take out all your trash. Beyond the stench, old garbage can attract curious animals who may be tempted to find a way inside.
- Unplug unused appliances such as lamps, televisions, and game stations.
- Make sure your house is as airtight as possible to keep the cold and critters out while you're gone.
If you're only leaving your home during the daytime hours while you're at work or running errands, it's fine to leave your thermostat alone. However, if you want to save money on your energy bills, adjusting your settings a few degrees cooler while you're away will make a difference.
What Temperature to Leave a Vacant House in Summer
If you plan to take an extended summer vacation or if you're a snowbird heading north for the warmer months, you can safely turn your thermostat up to 85 degrees. That setting will prevent sky high energy bills while still running your system often enough to reduce the threat of mold and mildew growth while you're gone. For additional tips on leaving your home for the summer, check out our AC Tips for Summer Vacation.
This temperature lowers cooling costs while protecting the house from extreme heat and humidity, which can harm electronics, drywall, and furniture. If the house is in a humid area, lower the thermostat to 78°F or 80°F to prevent potential mold and mildew from growing. A controlled thermostat allows you to maintain a consistent temperature and optimize energy efficiency while you're away.
If you don't already own one, investing in a programmable thermostat will make those adjustments easier. Another option is to upgrade to a smart thermostat, allowing you to control your temperature settings through an app on your phone. You may even have insights into humidity levels and air quality metrics. Some of the new models even include a geofencing option, using your phone's GPS to alert your system when you're nearing your home so it can adjust the temperature as you approach.
Like wintertime, if you're only leaving your home for the day, adjusting the thermostat a few degrees warmer while you are out will ease your cooling costs during the summer. Our recommendation for most locations is 78 degrees.
Whether you're leaving the house for a day, a week, or a few months, make sure your indoor air stays clean by replacing your dirty air filter before you go with one of our standard or custom-sized, affordable filters.
Does Climate Affect The Ideal Temperature For A Vacant House?
The appropriate temperature for an unoccupied house depends on the climate where it's located.
Climate has an effect on energy efficiency in the house. To keep the house safe and avoid frozen pipes in the winter, the thermostat should be at 55 degrees while during the summer a temperature of 85 degrees protects it from high heat and humidity. If you’re out of town during winter or summer, have someone adjust your thermostat for you to ensure your house is protected.
Should The Thermostat Remain Constant, Or Can It Fluctuate?
The thermostat in an empty house should stay at a constant temperature to keep the property safe. Temperature variations can increase the potential for problems like frozen pipes in the winter or high humidity in the summer. A programmed thermostat can help keep the temperature constant while making minor adjustments for variations, warmer settings during the winter or cooler settings at night during the summer. Maintaining a stable range prevents strain on your HVAC system and protects your home while it's unoccupied.
Are There Additional Measures To Take When Leaving A House Vacant?
Take these important additional steps to minimize risks when you’re gone:
- Turn Off Water Supply: To avoid any leaks or pipe bursts, turn off the main water valve.
- Insulate Pipes: Insulate pipes to keep them from freezing and breaking in the winter.
- Unplug Appliances: To save energy and prevent electrical risks, disconnect non-essentials.
- Secure Your Home: Use light timers, install a security system, and lock your windows and doors to keep your house safe.
- Examine the HVAC systems: Service heating and cooling systems before you leave to ensure they work properly while you’re gone.
- Remove Perishables: Remove perishable foods from your pantry and refrigerator, to avoid pests and odors while you’re away.
- Arrange for Maintenance: Pay someone to mow your lawn, shovel snow, and complete regular property inspections.
Should You Adjust The Temperature If The House Will Be Vacant For An Extended Period?
You can safeguard your house by adjusting the temperature when it will be empty for a long period of time. Temperature stays consistent when you use a programmable thermostat that can keep your home protected while also reducing your energy bills. Some programmable thermostats can adjust the temperature at various intervals. Another recommendation before you leave is to change your air filter so your HVAC system works properly.
What Happens If You Set The Temperature Too Low In Winter?
Lowering the temperature too much during winter could cause issues, including frozen pipes. Pipes can burst when they freeze, and cause water damage and expensive repairs. Condensation from extremely low interior temperatures can cause mold growth or damage walls, ceilings, and flooring. An environment that is too cold can make electronics and appliances malfunction. Protect your home from these problems by ensuring your temperature isn’t set too low.
What Risks Are Associated With Setting The Temperature Too High In Summer?
An unoccupied home can get hot and muggy during the summer if the temperature is set too high in your home, creating various hazards. Always run your AC while you are gone during the summer. Excessive humidity can warp wood doors, flooring, and furniture and cause mold or mildew issues. It can also affect appliances or electronics. Setting your thermostat between 78 and 85 degrees should protect your home from having these issues during hot summer months.
Are Smart Thermostats Useful For Vacant Homes?
You can upgrade to a smart thermostat, to conveniently control your temperature settings in your home with an app on your phone. It can also tell you your humidity levels and air quality metrics. Many new smart thermostat models have a geofencing feature that uses your phone’s GPS to notify your system when you're getting close to your house so it can adjust the temperature as you get closer.
Should You Notify Someone About The House Temperature While It's Vacant?
Notifying someone about the house temperature while it’s vacant is a wise move. Letting a reliable friend, neighbor, or property manager know allows them to keep an eye out for any problems with your house, like extreme temperature fluctuations, broken air conditioners, or frozen pipes. It's especially important during summer and winter when temperature swings can cause expensive damage. Giving instructions and your emergency contact information can offer peace of mind while you're gone by ensuring someone can act quickly in the event of an emergency.
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