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Ventilation guides

Practical advice on when and how to ventilate your home.

When to open windows in summer

How to use outdoor temperature swings for passive cooling — and the exact times that work in hot climates.

How to ventilate your home properly

Cross-ventilation, Stoßlüften, and other techniques that actually work. No expensive equipment needed.

Should you open windows at night?

Night ventilation can drop indoor temperature by 4–6°C before morning. Here's when it works and when to skip it.

How to cool your house without AC

Two-phase passive cooling: seal and shade by day, ventilate hard at night. How to use thermal mass as natural air conditioning.

Should you open windows when it's humid?

When humidity helps ventilation and when it causes mould. The 75–80% threshold and coastal climate exceptions.

Air quality and opening windows

What AQI level is safe to open windows? How to read the 0–500 scale, daily traffic patterns, and wildfire vs. Saharan dust episodes.

Ventilation during a heat wave

Why day 3 of a heat wave is hotter indoors than day 1 — and how to manage thermal mass accumulation and tropical nights.