Watershed Materials has introduced a sustainable masonry building block with half the cement of traditional concrete blocks.

Watershed Blocks fuse together locally sourced materials using the ancient building method known as rammed earth.

The manufacturing technology is patterned after the natural process that produces rock as pressure accumulates and loose soil grains are fused together into solid stone. Similarly, the company says, its factory process applies intense pressure to special soil blends of natural clays and other minerals.

Images: Watershed Materials

Watershed Blocks use locally sourced materials and about half the cement of traditional concrete blocks.

Mimicking the natural process called lithification, or rock growing, the company says it uses “a precise combination of rock fragments, quartz grains, feldspars, clays, and accessory minerals and then apply intense hydraulic force to mimic the weight of 20,000 feet of sediment.”

The result, the company says, is a structural, hollow-celled “industrial stone” that is as strong and durable as concrete using 65 percent less energy.

The company, founded in 2011, says the process can be reproduced anywhere in the world with local soil, crushed rock and even demolished buildings.

“Watershed Blocks have the visual complexity of sedimentary rock with a shape and design criteria that fit seamlessly into current masonry building typologies...,” the company says.

Watershed Blocks are made using a process called "lithification" to mimic how rock forms in nature.

Watershed Block contains:

• Between 51 percent and 58 percent less embodied energy than common gray concrete block; and
• Up to 67 percent less embodied energy than premium, finished grade architectural concrete block.

According to the manufacturer, the first home built entirely of Watershed Block in Napa, CA, sustained no structural damage during the recent magnitude 6.0 earthquake centered just miles away.

More information: www.watershedmaterials.com