We tested a brick that produces active shade

The idea is simple: what if a screen could change its opening through the day, without a motor or electricity?

The principle

Terracotta blades mounted on a timber axis, counterbalanced with an earth weight. A bimetal-like strip made of two different timber species deforms with relative humidity — and rotates the blade.

At noon, when the air is driest, the blades close. In the evening, as humidity rises, they open and let cool air through.

Prototype results

• Opening amplitude achieved: 34° (target: 45°)
• Response time: about 90 minutes
• Cost per m²: 2.3× a fixed screen
• Estimated durability: to be confirmed, tests ongoing

What it is worth

Honestly? It is not buildable yet. The response time is too slow and the cost premium too high for a thermal benefit we estimate at 1.5 °C.

But the path is open. We are continuing with a thinner strip version, and we will publish the drawings under an open licence whatever the outcome.