I Said Goodbye to the Outdated 66°F Heating Rule: Turning the Temperature Up Really Is Better for Your Home, Health, and the Planet
My bills didn't go up, we've been so comfortable, and all the condensation has disappeared
I spoke with HVAC professionals in November about how the outdated 66°F heating standard is outdated, and why raising the thermostat to 68-70°F this winter will protect your home, health, and the planet in 2026 and beyond.
Since I like to put my money where my mouth is, I’ve been testing the updated advice from the World Health Organization in my own home, raising the thermostat from our previous constant temperature of 66°F to 70°F for the last five weeks. The results have been excellent, with my family consistently more comfortable, no more condensation on windows, and crucially, my bills have surprisingly stayed the same.
The Changes I’ve Experienced at Home Since Turning the Heating Up
First, it’s important to note why the 66° Fahrenheit heating standard came to be. It began in the 1970s when there was an energy crisis, and the population was expected to help reduce the strain by turning thermostats down to 66°F.
HVAC pro Josh Mitchell, founder of Air Conditioner Lab explains, ‘That old 66°F guideline came out of the 1970s energy crisis. Energy costs were rising fast, so governments pushed for lower indoor temperatures to reduce demand. At the time, homes had weaker insulation, single-pane windows, and lots of air leakage. Comfort wasn’t the goal: Conservation was. The problem is that advice never evolved, even though buildings and heating systems did.’
Building materials and techniques were nowhere near as advanced as they are now, so all that happened at 66°F in the ‘70s was heat escaping through the walls, roof, and windows, wasting energy across the country and shortening supply further.
Now there are all different types of insulations, which are very effective, as well as improved building standards to make sure homes retain heat, or stay cool (both run on the same principles: Excellent insulation) all year round.
This means if you heat your home to the temperature the World Health Organization and many other health studies have proven to be better for your health and the planet, you will retain a constant, comfortable temperature indoors using less energy overall, and be less prone to illness.
Staying healthier is easier when your home is between 68-70°F, as low indoor temperatures impact how well the tiny cilia (hair-like structures) in your nose and lungs work, and these are vital in filtering out viruses and bacteria.
Multiple European studies, including a Cold Homes Public Health Review in Wales, UK, found homes heated to less than 64°F came with raised health risks, whilst the Marmot Review on fuel poverty found that it triple the risk of illnesses such as respiratory infections in winter. This was particularly true for vulnerable groups such as the elderly, ill and young.
HVAC expert Josh adds, ‘The World Health Organization now recommends a minimum temperature of 68°F for older adults and people with chronic illness. Studies have linked homes kept at or below 66°F with higher respiratory issues and more winter mold growth, especially in vulnerable households.’
I gave the new temperature standard of 70°F a try in my home for the last five weeks, and found it to bring a multitude of benefits. Here’s what I’ve learned and why I implore you to give the new heating standard a go. I'll definitely be sticking with it this winter and beyond.
1. My Family Has Felt More Comfortable Than Ever This Winter
We've slept better, felt more comfortable at all times of day, and been ill less.
After talking to HVAC pros and writing about the new home heating temperature standard in November, I immediately turned our smart thermostat up. Previously, I ran the heating constantly at 66°F because I worried about mold, illness, and high energy costs.
However, multiple newer studies, including the Marmot Review, have found that lower home temperatures leave people more vulnerable to illness, especially if they are already health-compromised, young, or elderly, prompting experts to warn that higher indoor temperatures are better for our wellbeing.
I fall into one of those categories as I am chronically ill, with a multitude of progressive illnesses that leave me in pain, limit my mobility, and wreak havoc on my immune and nervous system.
Since turning the temperature up, I have found it much easier to regulate my temperature, which is a daily battle otherwise due to my disautonomia (that is, dysfunction of your autonomic nervous system, which controls things you don’t think about, such as your body temperature, breathing, sleeping well, and more).
My daughter, who often picks up every virus going around at school, has been far less ill this December than in any other of her nine years of life. Last winter, her school attendance was low, at around 65% due to constant illnesses, and this winter, it’s been 95%. Whatever viruses my daughter did pick up this winter were passed in a couple of days rather than taking up to 10 days.
This is a correlation, of course, but it is quite coincidental timing, isn’t it? This is especially so with the very virulent strain of flu going around, and US cases rising by 25% in the last week alone. We have also been sleeping comfortably and no longer huddle under fluffy throws in the living room in the evenings to stay warm.
There’s been a marked and significant improvement in our comfort.
Josh adds, ‘From what you described, 69-70°F is where most people actually feel comfortable. In homes I’ve worked in, once the thermostat moves from 66°F to around 69°F, complaints about feeling cold usually stop. That small change matters more than people expect, especially for anyone sitting still for long periods.’
My husband and I both work from home in our small home office, and that extra comfort with boosted heating at home has meant my fingers are no longer cold and difficult to type with throughout the day.
2. My Windows Are No Longer Covered in Condensation Every Morning
Our windows, both on the first and second floor, are no longer covered in condensation in the mornings with the new heating standard in play.
Previously, I had to wipe off condensation from our bedroom windows every morning. If we were air-drying laundry overnight in the living room or kitchen, the windows there were covered in condensation, too. It didn’t take too much time to deal with, as I used microfiber cloths and shock ventilation techniques, but still, it was a hassle every morning, and crucial to prevent mold.
Since turning the temperature up to test the new heating standard, the condensation on our windows has disappeared.
HVAC pro Josh Mitchell explains, ‘At lower temps, indoor humidity hits the dew point faster on cold glass. In testing I’ve done, raising the indoor temperature from 66°F to 70°F reduced morning window condensation by roughly 50-60%. Less moisture on windows also means less mold risk around frames, curtains, and nearby walls.’
You can use an affordable hygrometer from Walmart to keep an eye on your home's indoor humidity. The ideal humidity for a house is 30-50%.
Our Bills Have Not Risen Despite the New Heating Standard
Ventilating your home and circulating fresh air when you're using the new heating standard is much less impactful on the planet and your bills.
Our newly built three-bed semi-detached house is all electric, and our bills have not budged from the usual $240 I pay monthly. I think we’re a particularly good example of why the previous heating standard really is outdated now, and the new heating standard should be between 68°F–70°F in winter.
Our walls and roof have excellent, high-tech insulation, meaning whatever heat is circulated in our home stays in our home. We also have well-sealed and fitted windows, so there are no rogue drafts there. I took care of the underdoor draft from our front door, meaning the comfortable 70°F has been very easy to maintain.
Josh says, ‘Your energy bill staying flat lines up with what I see. In all‑electric homes, each degree of heat usually adds around two to three percent in energy use. But when insulation and air sealing are decent, higher set points often lead to shorter heating runtimes and fewer recovery cycles. That offsets the increase. The system doesn’t have to fight temperature swings all day.’
I will add that in our bedrooms, we have felt a little hot overnight, so we've turned down the radiators from full blast to just 2/6.
Josh confirms this definitely saves on energy costs, adding, ‘Turning bedroom radiators down from 6 to 2 absolutely saves energy. It limits water flow, prevents overheating in small rooms, and lowers return temperatures. Bedrooms often hold heat overnight from bedding and body heat, so running radiators full blast there is wasted output.’
Ventilating the house and refreshing our air has been much easier and less impactful, too. Before, when I did shock ventilation for five minutes to refresh the air somewhat, the room felt positively cold afterwards for a number of hours.
Now, I am able to open windows or the door to the backyard for 10 minutes without the entire house feeling like an ice cube.
Josh adds, ‘Ventilating is easier when starting at 70°F instead of 66°F. This means you can open windows for 10 minutes without dumping the whole-house temperature. That clears cooking smells, moisture, and stale air without forcing long heating recovery cycles.’
This is better for your home, wallet, and the planet.
What to Shop
Point and shoot to instantly get the temperature of your surfaces. As HVAC pro Josh Mitchell explains, 'If your interior walls are below 60°F, you're running the risk of mold and other costly problems.'
Keep an eye on your indoor temperature and the humidity of your home. Aim to stay in the 30-50% humidity range to avoid mold, respiratory problems, and dry throats.
I use heatpads all over my home for pain relief and comfort. This is my favorite design. It has auto-shut off for safety, six heat settings, and timer options. Zone heating yourself means reduced energy costs and reduces winter aches and pains.
Our Sleep Editor Ottilie Blackhall swears by fleecy bedding to keep cozy all night long, without having to crank up the heat and drive up energy bills. She says, 'This hypoallergenic down alternative set traps heat, has a luxurious feel, and is machine washable.'
This small portable heater, available in four colors, comes with built-in safety features, including auto-shutoff and an anti-tipping design. You can spot-heat yourself or a colder room without a big bill, as these are economical to run.
Home Tech Editor and testing pro Dan Fauzi says, 'This is the smaller version of the Frigidaire dehumidifier we reviewed and loved. It has Wi-Fi connectivity and can alert you when it's time to empty the tank. It also comes with an allergy-reducing air filter.'
Meet the Expert
Josh founded AirConditionerLab over a decade ago, in 2014, with the aim to educate and inform readers about proper maintenance and care of their HVAC systems, and any significant mistakes they may be making, like placing their bed against an exterior wall, and how to avoid them.
As Josh sums up, ‘Most people stick to the old rules, thinking they’re saving money, but that’s often not the case with modern heating systems.’
I’ve tested the new heating standard, and it really is beneficial for your home, health, and the planet. You can also implement other tweaks to make winter more comfortable, including moving your bed a few inches to feel warmer as you sleep.
