TALKING TIMBER
Wood-based housing market possible in SA
By Dr Alec Basson
Researchers at Stellenbosch University ( SU ) found that South Africa has sufficient log resource options for a sustainable wood residential building market .
FACTS ABOUT TIMBER IN SA
• About 95 000 wood-based houses ( 172 % of current supply ) could be built annually .
• Only 1 % of new houses is wood-based , compared to more than 90 % in countries such as the USA , Canada and Australia .
• Timber is not only renewable , but is also the best performer across most environmental impact factors .
“
Our study showed that with the use of wood resources currently exported as chips , as well as planting trees in areas that have been earmarked for afforestation , it will be possible ( in the long term ) to sustain a future residential building market where all houses are built with wood ,” says Dr Philip Crafford from SU ’ s Department of Forest and Wood Science .
Dr Crafford and colleague Dr Brand Wessels investigated the country ’ s log resources and the potential global warming impact of an increasing wood-based residential building market . The findings of their study were published in the South African Journal of Science recently .
Dr Crafford says they wanted to determine whether local forest resources would be able to supply the required wood for substantial growth in wood-based residential development in South Africa . To do this , they analysed the residential housing footprint in the country ; available log resources for wood-based buildings ; and the likely environmental impacts of such a building system .
“ Due to the limited forest cover in South Africa , the perception is often that significant increases in the market share of wood-based buildings are not possible ( at least from local wood resources ). Our study showed that this perception is not correct .
“ If we consider only current available wood chips as a resource , 39 646 wood-based houses ( 30 523 houses and 9 123 flats ) could be built annually . With the afforestation resources , 55 314 houses ( 42 586 houses and 12 728 flats ) could be constructed each year . That is 1 203 more than the average new buildings in the past 17 years .
Considering both wood chips and afforestation resource potential , close to 95 000 wood-based houses ( 172 % of current supply ) could be built annually .” potential , only 1 % of new houses in the country is wood-based , compared to more than 90 % in countries such as the USA , Canada and Australia .
Dr Crafford says South Africa ’ s industrial round wood ( saw logs for everyday use ) production is mainly to produce pulp and board products ( 51 %), sawn lumber ( 24 %) and chip exports to Asia .
“ Over the past 10 years , we exported an average of 3.5 million tons of wood chips annually . Chip exports is the most likely available resource which could potentially be used in the building of wood-based houses .”
Regarding the environmental impact of a wood-based building residential market , Dr Crafford says numerous studies have shown that timber is not only renewable , but is also the best performer across most environmental impact factors when compared to alternative building material such as steel and concrete , with particularly good performance in terms of greenhouse gas emissions .
“ Our basic modelling analyses shows that if 20 % of new houses were to be built with wood , the amount of energy or fossil fuels required for production and the global warming potential of the residential building sector could decrease by 4.9 %. If all new constructions were wood based , this could decrease by up to 30 %.
“ This is quite a significant decrease if one considers that in South Africa , it is estimated that the energy used in the construction and use of buildings is responsible for about 27 % of the country ’ s total man-made carbon dioxide emissions . Wood-based building materials can help to reduce the environmental footprint of our residential buildings .”
Dr Crafford says that because South Africa does not have a culture of designing and building with wood , there ’ s a need for further research that includes other impacts such GDP generation , job creation and social and economic comparisons with regard to an increase in wood-based building .
Dr Alec Basson is a senior science writer at Stellenbosch University .
Source : Crafford , PL & Wessels , CB 2020 . South African log resource availability and potential environmental impact of timber construction . South African Journal of Science , Vol . 116 ( 7 / 8 ). https :// doi . org / 10.17159 / sajs . 2020 / 6419
Dr Crafford says that excluding imports and current pulp , board and other log resources , there could be an estimated 6.23 million cubic metres of log resources available for wood house components in the future . This amount of log resources would fill 6 019 Boeing 747s in volume or 55 377 double-decker City Sightseeing buses .
“ This clearly indicates the resource potential for an increased wood-based construction market in South Africa .” Despite this
1 . Timber has become a popular material in construction and design .
2 . Timber is a great finishing touch in architecture and design .
ALL IMAGES : STELLENBOSCH UNIVERSITY
28 DECEMBER 2020 / JANUARY 2021 // www . timberiq . co . za