Per-window advice
Close, crack open, open wide, or place a fan, based on weather and each window’s orientation.
App Store · Google Play
Ventilate.
At the right time.
Ventilate uses your home layout, window directions, indoor temperature, and local weather to tell you when to open, when to close, and how to place a fan, without air conditioning.
Your home
Building profile, cross-ventilation or single-sided layout, fan inventory.
Weather & transitions
Local forecasts and your next recommended action, with timely reminders.
On your device
No account. Your home data stays local. WeatherKit for weather only.
Heat, without panic.
Close during the day when it’s hotter outside. Open at night when the air cools. Place the fan in the right spot. Ventilate guides you, window by window.
Heat guides
The same advice that ships inside the Ventilate app, free to read. Six guides: ventilate the home, understand layout, judge whether outdoor air is worth letting in, stay cool, city heatwaves, and why cities get hotter.
Your home
When to ventilate, how layout sets the cooling ceiling, and whether outdoor air is worth letting in.
4 articles
How to ventilate your home during a heatwave
Your home is not a passive box. Opened and closed at the right hours, it can stay several degrees cooler than the street.
5 articles
How your apartment layout sets the cooling ceiling
Two flats on the same street can be several degrees apart. The difference is usually layout, not luck.
4 articles
When cooler air is not worth letting in
The free question is whether it is cooler outside. The next question is whether that cooler air is actually worth opening for.
Your comfort
Once the building is doing what it can: your body, drinks, pets, and plants.
Your city
Why nights stay hot, and which public choices actually change the temperature.
5 articles
Heatwaves in European cities, and why nights stay hot
The forecast is for the region. The air at your window is for your street, and streets hold heat.
2 articles
Why cities get hotter, and what actually cools them
Some of the heat in your flat was decided years ago, by what was built around you and what was paved over.
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Contact us
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