Ventilate · At the right time

Ventilate helps you stay cool during heatwaves with calm, practical guidance. Set up your windows once, add your indoor temperature (a thermometer helps but is not required), and get clear advice on when to close windows to keep heat out, when to open for fresh air, and where to place a fan so cool air reaches you. Uses local weather and your window directions for per-window recommendations, plus gentle reminders and a heat toolkit.