When considering sustainability solutions in architecture, constructing a building with earth is probably different from what first comes to mind. Sure, soil might theoretically be one of the most ‘ecological’ building materials, but is there anything we can truly build with earth beyond rustic structures?
In the past few years, compressed earth blocks (CEB) have begun offering a surprising answer to this question. The building material, made from a mix of local soil, non-expansive clay and aggregate, is a versatile, inexpensive and low-carbon alternative to construction.
Construction with compressed earth blocks has become increasingly popular in rural regions of some Sub-Saharan countries, where construction materials and equipment are expensive or hard to access. But architects elsewhere should also take note: compressed earth is proving to be more than just a material of necessity but also a versatile and architecturally exciting solution for sustainable projects that can be applied in both rural and urban areas.
In Rwanda, General Architecture Collaborative (GAC) incorporated compressed earth blocks into the design of the new Learning & Sports Center as part of its broader ecological and social equity mission. The firm’s project, 10th Annual A+Awards Jury Winner in both the Architecture +For Good and Architecture +Community categories, employed nearly 400 locals — more than half of them women — for the construction of these buildings.
Given the limited experience of locals with more complex building methods, GAC ensured the project adopted simple vernacular construction and designs, including screen weaving with local grass and bark and rainwater harvesting grids. Compressed earth blocks fell right in line with the design philosophy: made using the excess soil from the excavation, the compressed soil blocks were then used to make the walls of the new school buildings.