9 tips to keep your house cool without air conditioning

3 min read

In Vermont we are used to talking about how to stay warm and comfortable in the winter. But we do have a few months of the year when indoor temperatures can get too hot to handle. In fact, in a recent poll we conducted, more Vermonters said that they were “uncomfortable in the summer” than they were in the winter.  Hot climates have been using these passive cooling strategies for many generations. If the summer temperatures have you needing to chill out, try our tips.

1. Open your windows at night

In Vermont, temperatures drop during the night. Take advantage of cooler summer evenings and open your windows to promote a cross-breeze. Bonus: This can also help you sleep better! The cooler air will circulate all night, allowing you to start fresh with a cool home in the morning. In building science, this is referred to as night-flush ventilation. Don’t forget to close the windows and blinds before things get too hot in the morning.

2. Close your window coverings

Summer sun delivers heat right through your windows. Block the heat with shades or blinds during the sunniest hours to keep your home cool without AC. This is a passive, or “natural” cooling method that is one of the cheapest and simplest way to keep your home cool in summer.

3. Insulate and air seal your home

Many of the things that help keep your home warmer in the winter also help keep your home cooler in the summer. If you feel the temperature extremes in both seasons, consider a weatherization project. Cape-style homes and homes with varying ceiling height tend to overheat in the summer.  A professional weatherization project with an Efficiency Excellence Network contractor can fix the areas that make the home too hot in the summer and too cold in the winter.

4. Bake and wash at night

Large appliances give off significant amounts of heat. Wait to turn on your oven, range, dishwasher, and clothes washer until evening hours when temperatures are cooler. Also, consider hanging laundry outside to dry. You’ll save the cost of running the clothes dryer while reducing heat and moisture in the house.

5. Fire up the grill!

If you can, take your cooking outside. If hot food is in order, fire up the grill instead of turning on the oven. Summer is not the time to roast chicken or make lasagna. Instead, plan for grilled dishes and salads to avoid generating more heat in the house.

6. Install an exterior window shade

Installing an awning, pergola, porch, or shade trees by your west windows will shield your home from hot afternoon rays. Direct sunlight is like a heater in the cooling season!

7. Use your fans in the right places

Fans keep air moving around, rather than cooling the air. Blow air directly on people to get a cooling effect or set up your fans to draw in cooler air from the outside (or a cooler part of the house) to the warm areas.

8. Use your exhaust fans

Exhaust fans in your kitchens and bathrooms capture hot air before it mingles with your house air and contributes to overheating. Operate your exhaust fans during showers or whenever cooking indoors.

9. Set your ceiling fans to rotate counterclockwise

In the summer, the fan blades should rotate counterclockwise (as you look up at it) to push the air straight down. Increase the fan speed on the hottest days.

But what if you still need air conditioning?

These passive cooling techniques can’t cool down the house quite as much as a whole home AC (also known as central AC), a heat pump system, or a few well-placed ENERGY STAR rated window units, but they will make your house more comfortable. Even if you have efficient cooling equipment you can save by using passive cooling techniques. They can lower the temperature of your home so that if you do turn on the AC, you need less of it—and you waste less energy.