Timber is the new concrete, according to professor Alex de Rijke, former dean of the School of Architecture at the London College of Art and founder of dRMM architecture.
Mr de Rijke is currently in Australia to present a series of talks for WoodSolutions about the opportunities offered by engineered timbers for major construction, and to add fuel to calls for federal, state and local governments to adopt “wood encouragement” policies for publicly funded buildings.
Currently, there are four Australian councils promoting the use of engineered timbers – Latrobe Valley and Wellington Councils in Victoria, Kyogle Shire in NSW, and Wattle Range Council in South Australia. Rotorua council in New Zealand is also on board.
Mr de Rijke last week made a presentation to MPs from major parties at Parliament House in Canberra.
“We’re entering a new era of timber construction – super-modern buildings which are created faster, more cost effectively and way more sustainably using engineered timber,” Mr de Rijke said.
“Timber is the new concrete. The vast potential and versatility of engineered timber holds the key to construction for the 21st century, just as the 18th century was about brick, the 19th steel, and the 20th was concrete.”
COP21 could provide more impetus
Mr de Rijke told The Fifth Estate that given the role the construction sector has in relation to the global carbon footprint and energy use, it is logical to expect a flow-on effect from any climate targets agreed at COP21 in Paris.
“I expect timber construction to start entering the main debating arenas and climate change discussions,” he said.
Where Lendlease got the idea for Forte
In Europe, timber construction is seeing a revival, with building codes altered across the EU to permit the use of engineered timbers such as laminated veneer lumber, cross-laminated timber and glulam in multi-storey buildings.
It was almost used for the London Olympic Games Athletes Village accommodation. which dRMM designed for Lendlease, Mr de Rijke said. As with all the practice’s projects, the client had to be convinced timber would work out no more expensive than steel and concrete, and Mr de Rijke not only proved that point, he also took Lendlease representatives to Austria to see CLT and LVL being manufactured, and to see some examples of the new era of timber buildings.
While the concept was not used at the athletes village, the new awareness Lendlease gained about CLT was later put to good use in the design and construction of Forte and Library at the Dock, Mr de Rijke said.
Firemen prefer timber buildings
In 2005, his architecture practice designed the first all-timber house in London to be built since the Great Fire of London in 1666 AD. He said the design was approved through the UK equivalent of the Deemed To Satisfy pathway of the UK building code, and that his practice translated the German standard for timber buildings and its associated fire tests to demonstrate safety and compliance.
Mr de Rijke said fire brigades are actually happier to go into a burning mass timber building than a steel and concrete one, as research has shown the timber building is less likely to collapse and does not release the same hazardous toxins in the smoke as other materials.
Teachers stay put and kids perform better
His practice has also been designing school buildings using engineered timbers, and the anecdotal evidence is the students in those buildings are less stressed and that academic standards have improved compared to their previous performance in concrete and steel buildings.
The timber buildings are also making for happier teachers, and reducing staff churn, he said.
“If teachers love the place [they work] they will stay.”
In Austria, this effect has been quantified with studies showing students and staff have lower heart rates, and that there is an air of “calmness”, he said.
“With our UK projects we are demonstrating that no one needs to build sad steel sheds that pass for school halls and gyms when, for the same price, you can have beautiful timber buildings that inspire their users, and create an environmentally smart culture,” he said.
One of the major issues for timber construction in Australia is termites. Mr de Rijke said this meant the timber needed to be kept off the ground, by for example using the traditional Queensland style of building that raises the ground floor up off the ground on stumps, piers or steel saddle brackets.
Why move house when you can move the house too?
Another solution his studio has designed, called the Naked House, is a flat-packed prefabricated engineered timber building that fits into a shipping container and can be transported to anywhere in the world.
Once on site, the shipping container forms the foundation and lower level, and the building is assembled on top of it. It can also be easily disassembled, repacked and shifted to a new site if required.
Mr de Rijke said there needed to be “joined up thinking” around timber construction, which recognised the benefits in terms of absorbing carbon dioxide from growing trees, then the displacement of the carbon footprint of other materials that comes from building with sustainably harvested timbers. And once it’s in the building, that carbon is stored for life.
He said this needed to become common knowledge, and something every school child should know.
“The environmentally smart culture is in its infancy, but it’s coming. The fact I am addressing the industry as well as politicians is exciting.”
Alex de Rijke’s 21 reasons timber is better than steel and concrete
- Growing trees to use for timber construction not only absorbs carbon dioxide, but all kinds of other particulate pollution. Also, trees produce oxygen while they are growing. If we plant three trees for every one that is harvested, and live with trees as well as build with them, we have a healthier environment.
- The speed of engineered timber construction is faster than working in concrete or steel, and there is a reduced need for following trades such as plaster board installers because a product like CLT is also the interior finish.
- Engineered timber construction is more precise, due to the numerical control and accuracy that can be achieved in the prefabrication factories.
- A higher standard of quality control is achievable in the factory setting, and there is no risk of weather damage.
- Mass timbers are lighter – around one-fifth the weight of concrete, which means less foundations are required – this further reduces the need for concrete and shrinks costs.
- There is less need for on-site storage, and transport is simplified as building components are transported as flat packs on a just-in-time basis.
- CLT is a continuous structure.
- With CLT the structure is integrally braced and integrally strong – it is solid, not based on a frame and not reliant on joints or bracing.
- Timber is dry, clean and non-toxic to work with, making for a safer and cleaner site operation.
- Construction is a simple matter of assembly, specialist personnel are not required.
- It’s DIY friendly – building occupants can fix anything to anywhere on the walls, instead of searching for the timber stud behind plasterboard or drilling into concrete to hang a picture or mount a shelf.
- Services can be easily integrated, with penetrations pre-cut in the factory.
- It’s flexible – occupants or owners can change their minds about the building interior at any time, for example cutting additional doors or windows.
- The structure is the finish, interiors do not need plasterboard or paint, which reduces time, costs and materials.
- It’s durable, strong and repairable – concrete by contrast is extremely hard to repair.
- It’s warm – timber has its own thermal properties, so needs less insulation to get a very warm or cool building. This means it’s easy to go beyond code minimum. De Rijke’s practice has also used insulation that is manufactured from the sawdust waste created from mass timber manufacture.
- Timber is interesting – it has a tactile and sophisticated surface people are drawn to and interested in – unlike concrete.
- Timber is safe and healthy to inhabit and build with, and is non-toxic for trades such as lighting installers to drill into, giving off only sawdust and the smell of wood.
- Timber has intrinsic colour, and can be easily stained for different effects or enjoyed in its natural shades.
- It has a high level of compatibility with other materials due to easy connections, for example connecting steel brackets or constructing hybrid structures.
- “It’s just way more sexy than steel or concrete,” Mr de Rijke said. “People like wood.”