In a collaborative study on sustainable building materials, researchers from Spain’s University of Seville and Glasgow’s University of Strathclyde have created bricks that contain sheep’s wool and a polymer derived from seaweed. Clay-based soils were provided by Scottish brick manufacturers, while the wool came from Scotland's textile industry, which produces more of the stuff than it can use. The polymer was an alginate, which occurs naturally in the cell walls of seaweed. Mixed together, the three substances resulted in bricks that were reportedly 37 percent stronger than regular unfired bricks.

“These fibers improve the strength of compressed bricks, reduce the formation of fissures and deformities as a result of contraction, reduce drying time and increase the bricks' resistance to flexion,” the study’s authors concluded.

The bricks are environmentally-friendly in that they are composed of sustainable, non-toxic, locally-available materials, and don’t require the expenditure of energy that goes into the firing of other types of bricks – it wasn’t mentioned, incidentally, how their strength compared to that of fired bricks.

The wool-and-seaweed bricks also don’t create the carbon dioxide that is generated by the production of Portland cement, which is an ingredient in most types of concrete. There is no word yet from Seville or Strathclyde on whether or not there are plans to produce the bricks commercially.

The research was recently published in the journal Construction and Building Materials.