GreenBrick, the brick and moss facade that cools buildings

A facade system developed in Switzerland combines fired clay bricks with drought-resistant plants. It is called GreenBrick and is designed to cool buildings while limiting water use.

In the immediate surroundings of buildings the system can lower the temperature by up to four degrees. Consumption stops at 1.3 litres of water per day per square metre, well below that of traditional vertical gardens. Irrigation works in a closed loop and mainly uses rainwater.

How it works

The natural clay bricks serve a double purpose. They are building elements and at the same time a support for plant growth.

The cooling relies on evaporation. Moss holds moisture, while small potted plants such as ferns and geraniums shield it from direct sun.

The project grew out of collaboration between the Lucerne University of Applied Sciences, the Zurich University of Applied Sciences and several companies in the construction sector. The working groups bring together expertise in design, building technology, civil engineering and architecture.

The effects are not limited to temperature. The facade provides flowers and micro-habitats for insects, birds and small animals, and improves sound insulation by reducing the perception of traffic noise.

The structure is modular. Individual parts can be replaced or removed without touching the whole surface, and the system is compatible with suspended installations such as solar panels.

Its application concerns above all densely built historic districts, where ground-level space for greenery is limited. That condition is also found in the urban centres of Italian-speaking Switzerland, where free surfaces are scarce and summers are among the hottest in the country.