South Africans have been slow to embrace timber for housing and commercial construction, but this looks set to change. A combination of intensifying climate change and accelerating urbanisation is making wood more and more attractive as a building material.

“Wood is good,” said Professor Themba Mosia, Interim Vice-Chancellor and Principal of the University of Pretoria (UP), during the recent Innovation Africa @UP Growth Vision and Timber Design Competition Awards. The event was hosted by UP’s York Timbers Chair in Wood Structural Engineering, York Timbers, and the national Department of Trade, Industry and Competition.

This competition for architecture students across South Africa challenged them to find ways to build faster and better while reducing carbon emissions.

Setting the scene, Prof Mosia said the built environment was responsible for 40% of greenhouse-gas emissions globally, about a third of which are discharged during construction.

“Better designs and biomaterials are needed to meet the demand for new buildings while conserving the environment and ensuring that graduates are skilled for the world of work,” he said. “Timber is an incredible product that can be used in place of steel for high-rise buildings and homes,” he added, noting that South Africa needed to train architects, mechanical engineers, microbiologists and forest scientists, among others, to fuel the rapidly developing bioeconomy.

‘Bioeconomy’ refers to economic activity that uses and conserves biological resources. This concept was brought to life in the four winning entries for the 2024 Timber Design Competition.

Seeing the wood for the trees

For the competition, participants had to prepare conceptual designs for the expansion of UP’s Forestry and Agricultural Biotechnology Institute (FABI). FABI, which is part of Innovation Africa @UP, has experienced rapid growth in its forestry programmes and networks, and the three-storey building it occupies is smaller than originally planned.

“The foundations were built for seven storeys, but there was only budget for three,” explained FABI Director Prof Bernard Slippers.

This scenario lent itself perfectly to the 2024 Timber Design Competition, the second such competition that UP and its partners have presented. Unlike the 2023 competition, where the challenge was to design a rurally based biodiversity skills centre from scratch, this year’s competition imagined a taller, broader, or taller and broader version of the existing FABI building, using renewable resources – specifically wood and wood-engineered products.

Altogether, 32 entries were received, 13 of which were from UP students, 10 from the Tshwane University of Technology (TUT), five from Nelson Mandela University (NMU) and two each from the University of Johannesburg and the University of the Witwatersrand.

UP student with the most daring idea

The prize for the Most Daring Idea went to UP’s Simeon Jamison for his entry, “The Veil”. Simeon came up with the idea of using “bark cloth” to form the building’s “skin”, which would be planted with indigenous vegetation. The bark cloth would be woven from bark impregnated with resinous oils and harvested from the bark of trees in a plantation, without harming the trees. Simeon chose to expand the building outwards rather than building up.

First place overall went to NMU students Noa Solomon and Rudolph Botha for their “Blooming Branches” design, representing the trunk and branches of a tree. The tree metaphor guided the entire design, which involved building upwards and included a central hydroponics tower, solar panels and a composting system. Their chosen materials included cross-laminated timber, an engineered wood product known for its strength, versatility and durability.

Jasheen Thavalal of TUT won second prize for his “Timber Nexus” design, with hydroponic towers on the rooftop and tinted, recycled polycarbonate sheeting for the façade.

In third place were two other TUT students, Ntjidzi Grace Hikwa and Relebogile Mphahlele. Their design, “The Link”, mimicked the way eucalyptus cells are arranged, and featured greenhouses and hydroponic systems on the top-most floor.

Timber construction and climate change

During the evening, Nomalungelo Gina, Deputy Minister of Science and Innovation, congratulated UP and Innovation Africa @UP for hosting the awards. She highlighted the importance of timber in supporting South Africa’s commitments as a signatory to the Paris Agreement on climate change.

“Timber houses can be an important contributor,” she said, adding that active engagement was underway with the Department of Human Settlements. However, a shift to timber construction would have to go hand in hand with increased public awareness about alternatives to traditional building material, as well as the benefits of the bioeconomy.

“A change of mindset is needed among our people,” she said.

Michael Peter, CEO of Forestry South Africa, said that while the country has been a low adopter of timber in the built environment, “massive potential” is coming down the road.

“The Climate Change Act and the Public Procurement Act are going to change the trajectory of how wood is consumed,” he said. “There are great opportunities for the sector. We have never been more optimistic about the industry and are really excited about taking our work with UP forward.”