The Scientific and Industrial Research and Development Centre (SIRDC) is set to play its role in the provision of low cost building materials and construction technologies. Through its Building Technology Institute (BTI), SIRDC has perfected low cost roofing tiles and the rammed earth building technology. The micro-concrete roofing (MCR) tiles and the rammed earth construction technology are set to revolutionise the building materials and construction sector in this country and the region.
With increased and rapid urbanisation, housing provision has increasingly become a major problem in most cities and towns. The major issue relates to affordability. Conventional building materials and construction technologies are no longer affordable to the majority of home seekers. The MCR tiles utilisation and the rammed earth technology are set to play a major part in solving this national housing crisis as they will make housing affordable to about 80% of the people who need shelter.

The MCR technology originated in Latin America and SIRDC has adopted this technology for Zimbabwe through technology transfer arrangements. The MCR tiles conform to the Standards Association of Zimbabwe standard 863:2002. Each tile has an average mass of 2,8kg and 12 tiles cover a square metre.

For the purpose of enhancing their aesthetics, the MCR tiles come in five different and vibrant colours as well as a choice of two finishes: smooth or sand blasted, depending on an individual's preference or architectural specifications.

Some of the competitive advantages of MCR tiles are: they are 50% cheaper than the conventional roofing tiles, are light-weight (translating into considerable savings on roofing timber), have good acoustic qualities and are easy to lay.

The rammed earth technology is an “old” technology, which SIRDC has perfected. As the name implies, construction using this technology involves ramming earth material (soil) in steel or wooden formwork.

The earth material is free, save for the labour costs incurred in excavating the soil. Thus, it is truly a low cost technology.

Several houses around the Zimbabwe have been constructed using this technology. In the Cranborne and Breaside suburbs of Harare there are some houses that were built using rammed earth as far back as the 1950s. The fact that these structures have stood the test of time, withstanding harsh weather conditions such as cyclones and torrential rains, bears testimony to the durability of this building method.

In order to demonstrate the versatility of this building technology, a demonstration rammed earth house was built on the SIRDC premises in 1997. Recently, SIRDC built a rammed earth teacher’s house at the proposed site of Rukanda Secondary School in Mutoko in Mashonaland East Province. The house was roofed using MCR tiles. It is envisaged all the school's buildings will be constructed using the two technologies. The two low-cost technologies were quite a revelation to the Mutoko community and SIRDC is very grateful to Dr Olivia Muchena, Minister of Science and Technology Development for initiating, funding, and promoting the Mutoko rammed earth project which is still in progress.

An analysis of the costs incurred in building the two-bedroom Rukanda teacher’s house shows that construction using rammed earth and roofing with MCR tiles resulted in a low cost of $18 million compared to the $45 million it would have cost to build it using conventional technologies. An important point to note is that a good part of the $18 million was used for peripheral expenses such as transport, accommodation and allowances for the SIRDC technical staff who supervised the project.

SIRDC is building capacity to enable it to implement such projects on a large scale nationwide. The Centre is in the process of procuring additional equipment to boost its MCR tiles production capability. Plans are in place to establish tile manufacturing plants in all the country's 12 Provinces. The national project is set to commence in June 2004, by which time the tile production equipment is expected to have arrived into the country.

Besides making housing affordable to the majority of the population, these two SIRDC initiatives have the added advantage of employment creation. Youths are going to be trained to construct structures using rammed earth as well as making and laying the MCR tiles under the supervision of SIRDC qualified staff (as was the case in the Mutoko project). In addition, and perhaps more importantly, these low-cost technologies are ideal for the construction of decent houses, schools and health-care centres for the newly resettled farmers. It was therefore gratifying for SIRDC to hear through the Minister of Local Government, Public Works and National Housing, Dr. Ignatius Chombo, that government would soon be establishing a Housing and Infrastructure Bank to support the production of building materials. The bank is being set up as part of the National Housing Development Programme and will be accessible to companies and organisations such as SIRDC, who seek to ease the country's accommodation problems by producing affordable good quality building materials. Dr Chombo said this during his familiarization tour of the Mutoko rammed earth teachers house.

The effective execution and successful completion of its two projects make SIRDC confident that it is now poised to be of greater service and value to the country, especially at such times which are marked by tremendous challenges. hello