Aerobrick – a wonder brick

Aerobrick – a wonder brick

Swiss scientists with research group Empa have created a new insulating brick that would enable walls to conduct heat up to eight times better compared to a wall constructed from standard clay and shale bricks.

Aerobrick - a wonder brick -min

Aerobrick - a wonder brick -min
Picture 1 of 1

In order to achieve the same insulation values as a 165 mm thick wall of aerobricks, a wall of perlite bricks must be 263 mm thick - and a wall of non-insulating bricks even more than one meter!
photographs: Empa

Empa researchers have now replaced Perlite in insulating bricks with Aerogel: a highly porous solid with very high thermal insulation properties that can withstand temperatures of up to 300C (see box). It is not a novel material for the researchers: they have already used it to develop a high-performance insulating plaster which, among other things, allows historical buildings to be renovated energetically without affecting their appearance.

Together with his colleagues, Empa researcher Jannis Wernery from the research department, Building Energy Materials and Components, has developed a paste-like mixture of aerogel particles to be used as filler material for the brick. The material can easily be filled into the cavities and then joins with the clay of the bricks, says Wernery. The aerogel stays in the bricks – you can work with them as usual, thus giving birth to Aerobrick.

A comparison in a special measuring device for thermal conductivity at an average temperature of 10C shows that the perlite-filled bricks with the same structure and thickness insulate by about a third less than the aerobrick. In other words, in order to achieve the required insulation values, a wall of perlite brick must be about 35% thicker than an aerobrick wall.

Even more impressive is the comparison with ordinary brickwork made of non-insulating bricks: These conduct heat up to eight times better. A conventional wall would therefore have to be almost two metres deep in order to insulate as well as an aerobricks wall of just 20 centimetres in depth. With a measured thermal conductivity of just 59 milliwatts per square meter and Kelvin temperature difference, the Aerobrick is currently the best insulating brick in the world.

But now and in the very near future, no one will probably be able to build a new house from aerobricks û the filling material is currently still too expensive. Wernery calculates that at today’s market price for aerogel, a single square metre of a brick wall would generate additional costs of around 500 francs. However, experts assume that the costs for Aerogel will fall massively in the near to medium term then nothing will stand in the way of the use of the new wonder brick.

Leave a Reply