Rammed Earth Malindi

At an agroforestry project in combination with food processing, also a rammed earth pilot will be included. Finances are available for building affordable rammed earth accommodation and rammed earth cooling systems. The results of the pilot should provide a pathway for replicating the technology on a larger scale. Bob van der Bijl, is the CEO of the forestry project.

After a career at KPMG, and as director of the Netherlands-African Business Council, Bob van der Bijl decided to start an agroforestry project in Malindi, Kenya. The 200 hectare project is ongoing and a large area of trees has been planted and as such it is successful. Closer to Malindi, Bob is also developing a horticulture (fruit & vegetables) farm. Malindi is a beautiful area at the Kenyan coast, perfectly apt for tourism and the climate is suitable for tropical fruits and vegetables – provided sufficient water resources are available.

Bob van der Bijl explains how the rammed earth experiment is integrated in his project approach:

“I have been working in Kenya for over 6 years and in the past 3 years based in Malindi, in the coastal lowlands of Kenya. In previous jobs in various African countries, as well as over the past years in Kenya, it was clear that current building methods are not optimal: the “interior climate” of houses and buildings is not comfortable and especially in warmer climates the temperature rises sharply during the day and drops during the night – whereas a more stable indoor temperature would be preferable. Besides housing, there is also a need for storage at lower temperatures, for which usually air conditioning technology is used. Most current building methods are using a lot of cement or depend of excavation of rocks. A more sustainable method would need to be using less cement (= less carbon emission), less material that absorbs heat (= less concrete blocks or excavated stone blocks) and less material that has to be shipped from a larger distance. Given the low income per capita in most African countries, there is also a need for low-cost solutions. But besides low-cost solutions, there is also a growing middle and upper class that would be sensitive to a more comfortable living climate. Lastly, companies active in fresh vegetable produce and food processing would be interested in more cost-effective cold storage solutions.

After comparing several sustainable building technologies, rammed earth came out as one of the most promising technologies. A South-African architect specialized in rammed earth construction (Paul Marais from Simply Sustainable) visited Malindi to look at the possibilities. We have looked at using high quality and re-usable formwork from Peri (a German company specialising in formwork), but the cost of this system turned out to be very high. We now intend to work with local materials. We have identified a Dutch construction expert with experience in rammed earth, who lives at the coast and who can supervise and advise. Paul Marais can provide support from a distance.

We now want to work with locally produced formwork and build some examples of rammed earth buildings:

  1. Small cottages for an Ecorestoration Camp at CAAV – at a remote location 60km from Malindi where volunteers and tourists can stay. These cottages should be suitable for low cost housing and therefore this pilot should have the potential to be scaled up.
  2. A germination room / cold storage at the demonstration farm of ABC at Arabuko Farm, 15km from Malindi.
  3. A more up market 2 bedroom house that can function as a demonstration house for further project development in the coastal area – ABC has a 4000m2 plot where this can be built, based on the design of Simply Sustainable.

A student or a team of students can design and build a small rammed earth cottage and a storage room. For the more up market house, the students can assist the construction company that will be selected. Key items of the internship will be:

  1. establish the procedure to determine the right mix of earth based on local availability of soil and other inputs
  2. design and build the formwork using locally available materials
  3. decide on the use of equipment for compacting: electrical or manual labour
  4. design the cottages and storage room based on locally available material
  5. build the cottages and storage room(s)
  6. measure the effectiveness of the design in terms of interior climate
  7. assist in building the business case for scaling up
  8. up market house: assist construction specialist as a learning experience”