Indoor temperature affects health, not just comfort. The body’s ability to regulate heat and cold changes gradually with age. It may no longer be easy not to notice when a home has become too hot or too cold.

Here you’ll find information on how heat, cold, and humidity affect the body, what safe indoor temperature ranges look like, and what tools can help you monitor conditions at home. We also cover what to plan for during a power outage.

How aging affects the body’s ability to handle heat and cold

The body controls temperature through sweating, blood flow to the skin, and the heart and blood vessels. All of these change with age.

As we get older, we produce less sweat and the body becomes less able to move heat away from the skin when it gets hot. Some of these changes begin gradually in midlife and become more noticeable over time.

We may also become less sensitive to temperature changes. The body can be too hot or too cold before we feel it. Certain medications, including diuretics, beta blockers, antihistamines, and some antidepressants, can also affect how well the body manages temperature.

That’s why keeping a comfortable indoor temperature becomes more important as we age.

What heat, cold, and humidity do to the body

The National Institute on Aging recommends keeping indoor temperatures at least 68°F in winter. For older adults or people with health conditions, homes that stay between 60°F and 65°F can raise the risk of hypothermia, especially after several hours of exposure. Indoor temperatures above 80°F can raise the risk of heat-related illness, especially when it’s also humid and the home doesn’t cool down at night.

Heat-related illness often starts with painful muscle spasms called heat cramps. It can then move into heat exhaustion, with symptoms like heavy sweating, dizziness, weakness, nausea, headache, and fatigue. If the body doesn’t cool down, heat exhaustion can become heat stroke. Heat stroke is a medical emergency in which body temperature can rise above 104°F. It can cause confusion, fainting, seizures, and serious organ damage, and needs immediate medical care.

Cold affects the body in stages too, and the signs can vary from person to person. Early signs may include shivering, confusion, clumsiness, pale skin, and feeling unusually tired or slow. As the body cools further, shivering may stop. This is a warning sign that the body is getting too cold and needs help warming up.

Humidity, the amount of moisture in the air, also makes a big difference. High humidity in warm weather makes it harder for the body to cool itself through sweating. This can make a room feel much hotter than the thermometer shows. In winter, very dry air can irritate the skin, eyes, and airways and may make breathing harder for some people. The EPA recommends keeping indoor humidity between 30% and 50%.

Open windows and fans

Opening windows when it’s hot and humid outside can bring warm, sticky air indoors and make cooling harder. In winter, drafts from windows and doors can cause a home to lose heat faster, especially in homes that aren’t well insulated.

Fans can help in mild to moderate heat, when the body is still able to cool itself through sweating. In extreme heat, fans may not work as well. When temperatures are very high and humidity is also high, fans can lose their cooling effect. Research published in JAMA found that in these conditions, electric fans did not consistently lower body temperature in older adults. In some cases, fans may make things worse by speeding up fluid loss without providing enough cooling. Because of this, fans should not be the only cooling tool you rely on during extreme heat. How well a fan works depends on the temperature, the humidity, how hydrated you are, and your overall health.

When it’s hot outside, it also helps to avoid using the stove, oven, dishwasher, washing machine, and clothes dryer. All of these add heat to your home.

Checking both temperature and humidity together gives a clearer picture of how safe and comfortable your home really is.

Best ways to monitor home temperature remotely

There are 3 main types of tools for monitoring indoor temperature. Each works a little differently and suits different needs. Even using a monitor in your own home can be helpful. It can alert you when the temperature is outside a safe and healthy range.

Standalone temperature and humidity sensors

These small, affordable devices sit in any room and send temperature and humidity readings to a smartphone app in real time. You can set your own alert levels, and the app will notify you if conditions move outside the range you choose. These devices monitor and report conditions only. They do not control your thermostat or adjust the heat or cooling in your home.

The Govee WiFi Thermo-Hygrometer, SensorPush HT1, and Caregiver Smart Solutions Temperature and Humidity Sensor are all examples of this type of device.

One important thing to know is how the sensor connects to your phone. Bluetooth-only sensors can only send data when a paired phone or hub is within Bluetooth range, meaning they need to be in or near the home to work. If you want to check conditions while you’re away from home, choose a sensor that connects to the internet through built-in WiFi or a compatible hub or gateway.

Many WiFi sensors connect only to 2.4 GHz networks. These networks have better range and can reach through walls better than 5 GHz networks. Before you buy, check that the sensor works with your home’s WiFi network.

Most standalone sensors have no monthly fees. Many let more than 1 family member view readings and get alerts through the same app. Some have a small screen on the device that shows the current temperature and humidity. Others show readings only in the app.

Smart thermostats

Smart thermostats connect directly to your home’s heating and cooling system. They let you check and adjust the temperature from anywhere using a smartphone app. You can view current conditions, set schedules, change the temperature from a distance, and get alerts if temps move outside the range you set.

The Nest Learning Thermostat and Ecobee are widely used options that include full remote access and app control. The Honeywell Home line includes both WiFi and non-WiFi models, so make sure the model you’re looking at includes app access before you buy.

Not all smart thermostats work with every heating and cooling system. Some homes don’t have a common wire, called a C-wire. Those homes may need an adapter or power kit to install a smart thermostat.

Whole-home monitoring systems

Whole-home monitoring systems use a set of sensors placed around the home to track temperature, humidity, motion, and daily routines over time. Many send alerts when routines change. This can be helpful for families who support someone living on their own.

These systems usually require a monthly fee. They include cloud-based monitoring and extra features for remote caregivers. EnvoyatHome is one example built specifically to support aging in place.

Which option is right for you?

A standalone sensor is an affordable way to monitor temperature and humidity in a specific room. A smart thermostat lets you adjust your home’s heating and cooling from anywhere. A whole-home monitoring system gives families a fuller picture of conditions and daily activity at home.

No matter which option you choose, look for customizable alerts, a reliable smartphone app, and the ability to share access with more than 1 family member. Those features make it easier to stay informed and act quickly if conditions change.

When the power goes out 

A temperature sensor can only send data when it has both power and an internet connection. During a power outage, both are usually cut off. Some devices may send a “device offline” alert when they lose connection. This can be an early sign that something has changed at home. It’s worth checking whether a device you’re considering offers this type of alert.

Beyond the sensor going offline, power outages create their own temperature risks.

In winter, a home will start losing heat as soon as the heating system stops working. How fast indoor temperatures drop depends on things like insulation, home size, window quality, and outdoor conditions. In very cold weather, indoor temperatures can become unsafe within a few hours in a poorly insulated home. In milder conditions, the drop is slower. The risk of cold-related illness goes up as indoor temperatures keep falling, especially for older adults and people with ongoing health conditions.

In summer, a home without air conditioning can heat up fast, especially in direct sun or in a poorly insulated building. Temperatures may keep rising throughout the day and can stay high into the evening or overnight. This raises the risk of heat-related illness.

Weather-related power outages have become more common in many parts of the country, especially those tied to extreme heat and cold. How long an outage lasts depends on where you live and how severe the storm is, but many last several hours or more. Having a plan in place before extreme weather hits can make a real difference in staying safe and comfortable.

Finding cooling and warming centers near you

When your home gets too hot or too cold to stay comfortable, or if the power goes out for a long time, it helps to know where local cooling and warming centers are before you need them.

Cooling centers are air-conditioned public spaces, such as libraries, community centers, or recreation centers, that open during periods of extreme heat. Warming centers serve the same purpose during cold-weather emergencies. These sites are usually free, though hours and availability vary by location.

One of the easiest ways to find a center near you is to call 211. In the United States, 211 is a free service that connects you to local health and social services. This includes the locations of active cooling or warming centers in your area. In many areas, you can also reach 211 by text or online chat, though this varies by region. Calling 211 can also connect you to other basic needs resources like housing help, food banks, and utility assistance.

Libraries and community centers are often air-conditioned in summer and heated in winter. They can be a good option during the day, even when no formal center has been opened. Shopping malls can offer similar relief, though hours and availability vary.

Some cooling and warming centers only open when a weather emergency has been declared. Checking with your local health department or calling 211 ahead of time helps you know what’s available in your area before you need it.

Knowing your options ahead of time means you won’t be searching for help in the middle of extreme weather.

Planning makes the difference

Keeping tabs on the temperature inside your home, or a loved one’s home, doesn’t have to be complicated. A single WiFi-enabled sensor can provide up-to-date temperature and humidity readings, along with alerts you can check from anywhere. A smart thermostat adds the ability to adjust heating and cooling from a distance. And in many areas, information about the nearest cooling or warming center can be found through 211 or your local health department.

The tools covered here are practical and easy to find. Many are affordable, depending on what level of monitoring you choose. Having them in place before extreme weather arrives makes it easier to respond when conditions change.

Temperature is one part of a larger picture of comfort and safety at home. Having clear, timely information makes it easier to make good decisions about your home environment year-round.

Sources

• National Institute on Aging: hot weather safety, cold weather safety, hypothermia
• Harvard Health: extreme heat, power outage health protection
• Cleveland Clinic: heat exhaustion, heat stroke, hypothermia stages
• Centers for Disease Control and Prevention: heat-related illness
• Dr. Fergus O’Connor, Griffith University: sweating capacity and aging
• Journal of the American Medical Association: electric fan effectiveness in older adults
• EPA: indoor humidity recommendations
• Center for American Progress: power outage frequency data
• American Lung Association: medical device power outage planning
• Govee, SensorPush, Caregiver Smart Solutions, EnvoyatHome: product information
• Sources: National Center for Healthy Housing, 211.org, New York State Department of Health, LA County Emergency Management. 

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