Compressed Earth Blocks (CEBs) are natural masonry blocks produced hydraulically using an Earth Block press. A wide range of soils can be used for the production of these blocks with the key ingredients being clay and sand. These blocks are laid in standard masonry fashion and can be laid in mortar, a clay slurry, or dry stacked. - Building Info.
Soils: Your Natural Resource
Earth Blocks are typically made from the soils found directly on site or in the local area. Often we are able to take the soils from an excavated foundation and press them into blocks for the construction of the building’s walls. If the soils are not found on site, they can often be found at other local building sites or quarries.
Soils suitable for block making require a clay content between 15-30% with the remainder being primarily sand and silt. If a soil is too high in clay or sand, it can be amended with the addition of sand or clay respectively. Sometimes the soil requires screening if there is large aggregate like rocks present. Organic matter is not used for block production, so the precious topsoil can be used for growing flowers, grass, or veggies.
Mixing and Stabilizing
Prior to block making the soil is prepared by mixing in a stabilizer such as lime, which will enhance the weather resistance and compressive strength of the CEBs. The moisture content of the soil mix at this time needs to be approximately 10%, which is not very wet.
The soil mixture is dumped into the hopper of the block machine with a front-end loader. It feeds into a 4” x 14” mold in which the soil is hydraulically pressed from two sides. The block width can quickly be adjusted for sizes between 2-10 inches to meet architectural needs.
Blocks require a minimum of two weeks curing time during which they are covered
to maintain high humidity and temperature.
The Finished Block
Once curing is complete, our blocks have a compressive strength of approximately
700-1,500psi (pounds per square inch). These blocks are load-bearing, and are
appropriate for above grade/ground exterior and interior wall construction. On the
exterior earth blocks are finished with a stucco, plaster, render, or even siding.
Block Size: 14” x 4” (length x height)
Block Width: 2” to 10” adjustable
Compressive Strength: 700-1,500 p.s.i.
Weight: 30 lbs for a 7”x14”x4” block