Housing in Southern Africa October 2015

THE A B C The Eric Molobi Housing Innovation Hub’s scope and mandate is to provide research on new Innovative Building Technologies (IBTs) and products. The hub plays a crucial role in assessing the technical and physical performance of these systems at its testing facilities in Soshanguve, Tshwane.

T he hub’s village style atmo- sphere with a range of Inno- vative Building Technologies show houses, clearly demonstrates the aesthetic appeal of the numer- ous housing styles, from emergency housing units to double storey resi- dential units. The diversity of systems, their look and consumer appeal is just eye candy. The most important as- pect is how these systems perform technically, scientifically and the buildings' performanceandwear and tear on site. Innovation by definition means ‘the introduction of something new: a new idea, method, or product etc’. An IBT is defined as any form of building which utilises building sys- tems, methods, materials, elements or components, which are not fully covered by existing standards and specifications or codes of practice and/or referred to in the ‘deemed- to-satisfy’ of the National Building Regulations. Innovative building technologies are required to have either an Agré- ment certification or (for the purpose of housing specifically) the National Home Builders Registration Council (NHBRC) Rational Design approval, in order to comply with the building regulations. The National Home Builders Reg- istration Council, Centre for Research and Housing Innovation’s hub evalu- ates, tests and approves systems to ensure that the IBT is fit for pur-

of this material available. The con- crete walls are usually constructed in-situ or precast in a controlled factory environment and then as- sembled as panels on site. FORMWORK SYSTEMS MOLADI The Moladi housing system is a typi- cal cast in-situ, concrete forming sys- tem. A lightweight plastic injection mould formwork system is used to cast the wall. The reinforcing of the walls of the superstructure must be designed and certified by a structural engineer. The walls are comprised of an in situ cast, reinforced 100 mm thick walling system, consisting of reinforcedmesh and aeratedmortar. This mortar comprises a mixture of graded river sand, cement, water and Moladi Chem, the company’s own chemical component. The external and internal wall thickness is 100 – 150 mm. No beam filling is required as block outs are used to create the cavities to position purlins and trusses accurately. Steel windows and doors are cast into position. All electrical and water piping is

pose. Some of the criteria that is investigated/evaluated includes: structural strength and stability, serviceability, materials, behaviour in fire, energy efficiency and instal- lation of services (water and sewer). With the public and private sector upscaling the speed of housing deliv- ery and so many systems available, alternative solutions can be found in IBTs. There are two main categories of innovative building technologies, based on wall type – masonry and non-masonry. A masonry wall can be defined as an assemblage of masonry units jointed together withmortar to form a structure and are either generally made from fired clay, concrete or compressed soil. Every other wall type that does not fall within this description is a non-masonry wall. CONCRETE Concrete based walling systems, in various forms, are more common than many people realise and have been in existence for decades. Con- crete is one of the oldest building materials and there is a wealth of technical knowledge and experience

MOLADI

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