12 Advantages of building with rammed earth in Africa
Updated: Dec 31, 2022
Rammed earth construction is quickly becoming popular with Africans and people in the diaspora looking to return home and live a cleaner more eco-friendly lifestyle. Rammed Earth Construction is basically using the Earth under your feet or from a local quarry to build a wall, house, school, or anything you can think of. It's a great eco alternative since it required little to no cement or iron rods, and it's non-toxic as it's natural.
Advantages of rammed earth:
100% Natural & Non-toxic
Laterite, clay, and aggregates; these are all materials that are abundantly available in Africa.
When constructing a rammed earth building, in some cases these materials can also be found on the site or within close proximity to the construction site.
In the past, we have used materials on the site to build schools, libraries, and community centers. When constructing unstabilized earth walls consists of having a mix with no cement, therefore making all materials in your mix 100% local and natural.
Because you are only using natural materials when building a structure with rammed earth, you don’t need to worry about any toxic substances being part of the manufacturing process.
Very low carbon footprint
The process of building with rammed earth walls creates a very low carbon footprint. Unlike building with conventional building methods i.e. concrete this uses around 10-20% cement which in itself as a material goes through a process and contributes greatly to air pollution. The process that is also used to extract natural resources consumes energy and causes environmental degradation.
With rammed earth construction, materials are sourced locally and don’t go through a process in order for it to be suitable to build with, it is simply extracted from the site, add a little water to create a damp mix and then its ready to use.
Rammed construction tends to be more labor intensive, if you’re doing it on a small scale it uses little to no machinery.
Great for indoor climate
Rammed earth walls have great thermal mass because they are dense and heavy, so it can absorb and store significant amounts of heat.
Walls constructed using rammed earth contain less than one-twentieth of the embodied energy of traditional brick-and-mortar walls.
Rammed Earth walls have a high thermal mass absorbing heat energy through the day and releasing it into the building as temperatures fall at night. Experiments have shown that rammed earth walls can actually reduce daytime temperatures by 4 or 5 degrees.
Earth walls control humidity levels within buildings by absorbing excess water vapor and releasing it back when the environment is drier. This is particularly good for cities like Accra where the humidity is particularly high and can be at times uncomfortable. Rammed earth walls give an overall better indoor air quality and a healthier, cleaner home overall. Rammed earth also has a detoxifying effect, it’s a living breathing material and has the ability to absorb toxins and smells from the indoor air.
Earth is a material that isn’t combustible. A 300 mm thick wall has a fire resistance of up to 4 hours.
Taking out labor cost, Rammed Earth construction can be very affordable. If you are able to find all suitable materials on or close to the construction site your spending next to nothing on materials.
Tools that are needed to construct Rammed Earth walls can also be low cost and basic, re-in forced ply wood boards for your form works can be purchased at your local hardware store. You will need something solid to compact the earth, something as basic as a log of wood is suitable.
Life cycle cost
Having an earth home is very low maintenance. Because of how rammed earth walls are constructed they can achieve a high compressive strength and dense compaction.