Porotherm

Brick construction is still widely used in Warsaw, but from my observations, there is only one dominant company and type of brick: the Wienerberger Porotherm. These blocks are quite large- they can be over 30cm thick- but are still light enough to be handled by one worker. This is due to their honeycomb-like structure, with many thin walls of clay. Their structure and composition also makes them good insulators, which would explain their popularity.

Wienerberger is, according to their website, the 'world's largest producer of bricks'. Production, however, is decentralized, and many countries have multiple quarries and factories all producing brick to Wienerberger specifications. There are thirteen in Poland, with the nearest to Warsaw being Zielonka, less than 20km away. The standardized properties include size, shape, and recipe- some of their clay blocks call for the addition of sawdust to the raw clay, which burns off in the kiln to produce microscopic air pockets, thus increasing the insulation value. 

The Porotherm is obviously meant to be hidden, and is normally used as infill for a concrete frame, but the idea of insulating bricks is an interesting one. It opens up the possibility of returning to monolithic brick construction, but with more performative modules that could serve as structure, insulation, and cladding.