The feasibility of wood plastic composites as building material for RDP houses in South Africa

Thesis (MScFor)--Stellenbosch University, 2020.

ENGLISH ABSTRACT: The South African Government is faced with numerous environmental, economic and social challenges. Invasive alien plants (IAPs) are environmental threats, which change the ecosystems they invade. The Working for Water (WfW) Programme is a pioneering environmental initiative working under the Department of Environmental Affairs (DEA), which aims to eradicate IAPs. The value-added industry (VAI) launched under the WfW Programme aims to use these cleared IAPs for economic benefits. Plastic pollution is another global and national environmental issue caused by increasing population and industrialization. Numerous organizations have created awareness pertaining to this issue and the importance and benefits of recycling plastic waste. The objective of this study was to assess the feasibility of producing wood plastic composites (WPCs) as a building material made from woody IAPs and recycled plastic for low cost buildings through a hypothetical small business initiative. WPCs can be deemed as green products since they use recycled material, renewable resources and minimize the impact they have on the environment. Small business development is being encouraged to address the national unemployment rate. A feasibility study was conducted to assess the success of a proposed small WPC business. The feasibility study assumed that the project would take place in the Western Cape and Acacia saligna sourced along the Berg River and recycled LLDPE plastic from Bellville would be used for production. A survey was conducted in the Kayamandi Township to study the living conditions of people living in the RDP houses and observe any infrastructural defects. This would help identify a potential building structure replacement made from WPC material. Based on the survey results, 14% of the respondents complained about defective ceiling boards thus, a potential building component was recognized. Another part of the study was to determine the economic and financial perspective of manufacturing WPC ceiling boards, whereby the procurement costs of the raw material including the harvesting, purchasing and transport of these raw materials was considered. Two WPC ceiling boards with different dimensions were proposed. Type A being 1 m2, with a thickness of 0.004 m (research prototype) and Type B with dimensions 3 m x 1.2 m x 0.004 m (commercial competitor) were proposed. Both options were found to be profitable for a small business initiative. The sample boards used for testing mechanical and physical properties exceeded the benchmark values of gypsum ceiling boards in all analysed properties. The results showed that Type B boards could potentially replace the currently used gypsum ceiling boards of the same dimensions. In addition, the budgeted statement of profit or loss and comprehensive income showed a higher net profit after tax when compared to Type A boards. The mark-up percentages on cost of goods sold ensured that the selling prices per unit exceeded break-even prices resulting to selling prices (SP) of R90.16 and R120.76 for Type A boards and Type B boards per unit, respectively. This would allow the business to generate some profit. The net-present value (NPV) for the two board type investments were positive, however as a rule of thumb, the investment having the highest NPV value should be pursued. Therefore, the Type B boards would be recommended as a product to be sold in the small business. A sensitivity analysis was conducted to determine the effects of different input scenarios on the forecast break-even points. A change in selling price is highly sensitive as that determines the contribution margin of the business.

AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse regering word deur talle omgewings-, ekonomiese en maatskaplike uitdagings gekonfronteer. Indringerplante (indringerplante) is omgewingsbedreigings wat die ekosisteme wat hulle binnedring verander. Die Working for Water (WfW) -program is 'n baanbrekende omgewingsinisiatief wat onder die Departement van Omgewingsake (DEA) werk, met die doel om IAP's uit te wis. Die toegevoegde waarde-industrie (VAI) wat in die loop van die WfW-program van stapel gestuur is, is daarop gemik om hierdie skoongemaakte IAP's vir ekonomiese voordele te gebruik. Plastiese besoedeling is nog 'n wêreldwye en nasionale omgewingskwessie wat veroorsaak word deur toenemende bevolking en industrialisasie. Talle organisasies het bewustheid rakende hierdie kwessie en die belangrikheid en voordele van die herwinning van plastiekafval geskep. Die doel van hierdie studie was om die lewensvatbaarheid van die vervaardiging van houtplastiese komposiete (WPC's) as 'n boumateriaal wat van hardhoutagtige IAP's en herwinde plastiek vir lae koste geboue vervaardig word, te evalueer deur middel van 'n hipotetiese klein ondernemingsinisiatief. WPC's kan as groen produkte beskou word, aangesien dit herwinde materiaal, hernubare hulpbronne gebruik en die impak wat dit op die omgewing het, tot die minimum beperk. Die ontwikkeling van kleinsakeondernemings word aangemoedig om die nasionale werkloosheidsyfer aan te spreek. 'n Uitvoerbaarheidstudie is uitgevoer om die sukses van 'n voorgestelde klein WPC-onderneming te beoordeel. Die uitvoerbaarheidstudie het aanvaar dat die projek in die Wes-Kaap sou plaasvind en dat Acacia saligna langs die Bergrivier verkry word en dat herwinde LLDPE-plastiek uit Bellville vir produksie gebruik sou word. In die Kayamandi-township is 'n opname gedoen om die lewensomstandighede van mense wat in die Hop-huise woon, te ondersoek en infrastruktuurfoute op te spoor. Dit sal help om 'n moontlike vervanging van boustrukture uit WPC-materiaal te bepaal. Op grond van die resultate van die opname het 14% van die respondente gekla oor gebrekkige plafonborde, dus is 'n potensiële boukomponent erken. 'n Ander deel van die studie was om die ekonomiese en finansiële perspektief van die vervaardiging van WPC-plafonborde vas te stel, waardeur die verkrygingskoste van die grondstof, insluitend die oes, aankoop en vervoer van hierdie grondstowwe, oorweeg is. Twee WPC-plafonborde met verskillende afmetings is voorgestel. Tipe A is 1 m2, met 'n dikte van 0.004 m (navorsingsprototipe) en tipe B met afmetings 3 m x 1.2 m x 0.004 m (kommersiële mededinger). Daar is gevind dat beide opsies winsgewend is vir 'n klein ondernemingsinisiatief. Die monsterborde wat gebruik is vir die toets van meganiese en fisiese eienskappe het die normwaardes van gipsplafonborde in alle ontleed eienskappe oorskry. Die resultate het getoon dat tipe B-planke moontlik die huidige gebruikte gipsplafonborde van dieselfde afmetings kan vervang. Daarbenewens het die begrote staat van wins of verlies en omvattende inkomste 'n hoër netto wins na belasting getoon in vergelyking met Tipe A-direksies. Die winspersentasies op die koste van die verkoopte goedere het verseker dat die verkooppryse per eenheid gelykbreekpryse oorskry het, wat die verkooppryse (SP) van onderskeidelik R90.16 en R120.76 beloop het vir tipe A-borde en tipe B-borde per eenheid. Dit kan die onderneming 'n bietjie wins oplewer. Die netto huidige waarde (NPV) vir die twee boordtypebeleggings was positief, maar as 'n reël, moet die belegging met die hoogste NPV-waarde nagestreef word. Daarom word die tipe B-planke aanbeveel as 'n produk wat in die kleinsakeonderneming verkoop sal word. 'n Sensitiwiteitsanalise is uitgevoer om die gevolge van verskillende inset scenario's op die voorspelde gelykbreekpunte te bepaal. 'n Verandering in verkoopprys is baie sensitief, aangesien dit die bydrae van die onderneming bepaal.

Masters