Rammed earth construction is an ancient method where a mixture of damp earth and a stabilizing agent is compressed into formwork. The mixture is placed and compacted in layers until the desired wall height is reached. Although rammed earth construction can be somewhat labor-intensive, the technology saves on material cost since the earth used is often subsoil from the construction site.
When properly planned and constructed, rammed earth walls are unaffected by rain, fire or pests. The walls are load bearing and don’t require any further finishing. The structures act like breathing walls, allowing air exchange without significant heat loss.
The rammed earth material also works naturally as a thermal mass, storing heat in winter and rejecting in the summer. The passive system creates a stable, balanced temperature and humidity which can eliminate the need for air conditioning.
Aesthetically, the layers of earth produce tonal, gradated stripes and inherently warm color.
If suitable soils and adequate soil quantities are available, rammed earth buildings can be adapted to any climate. A research project of building with rammed earth at MIT demonstrated that the method can be applied even in New England.
Examples of rammed earth projects from around the world are pictured below: