Architects, designers, engineers, planners and manufacturers gathered in London earlier this month to participate in a roundtable discussion on how timber can and should be used to meet the construction challenges they face.

The talks focused on how wooden materials can ease Britain’s housing crisis – it is projected that London alone requires 60,000 new houses a year, double the current rate, to meet demand – but the discussion also touched more generally on the urgent need for fast and sustainable construction methods across building sectors in an age of urbanisation.

The event was hosted by specialist manufacturer Metsä Wood – which believes modern timber materials can “enable several storeys to be constructed on top of existing structures, allowing us to build up and stop tearing down.”

Topics discussed included the energy performance of new builds created using timber; the benefits of hybrid construction, using a range of materials including steel, concrete, brick and timber; and the need to raise awareness of the cost benefits of wooden materials.

“We find there’s still a lot of anxiety and lack of knowledge [among architects and developers], particularly on cost,” said Rory Bergin, a partner of architecture studio HTA Design. “The way to further innovation is to push at the sweet spots where the benefits are indisputable to the client.”

Nick Milestone, managing director of hybrid engineering firm B & K Structures, added: “The people we need to convince are quantity surveyors. I’m starting to see that firms are now measuring the costs of engineered timber against traditional construction. They are saying to developers they can now build it quicker, lighter and cheaper. It is now a competitive solution, because reinforced concrete is becoming very expensive.”

Linda Thiel of Sweden’s White Arkitekter discussed how timber can be used for commercial and public buildings, as well as housing, particularly in urban areas where space is at a premium.

“Too often engineered timber is being used simply to replace concrete,” she said. “Once designers see it as a different material, design will flourish and create a new architecture.”

In order to explore this idea further, Metsä Wood recently ran a competition, called “City above the City’, inviting architects to design timber structure extensions to existing urban buildings in 69 cities worldwide, including Sydney, Shanghai, New York, Berlin, Paris and London.

Explaining its reason for promoting the potential of timber in this way, the company said: “Research shows that approximately a quarter of existing buildings are strong enough to carry additional floors made of wood. Moreover, it is the only material light enough to build quickly on to existing structures.

“This makes wood a highly promising building material for providing living space for billions of people – while also preserving the architectural heritage of our cities.”

Case Study

Kalpana Gurung and Robert Buss from Studio Hoopla demonstrate how timber extensions could revive a threatened London market

Chrisp Street Market is a 3.6 hectare site near Canary Wharf, built in the 1950s as part of the Festival of Britain, and having been active as a street market since Victorian times. There are currently plans to build 750 new homes while upgrading the existing retail units.

However, according to Gurung and Buss, this proposal will “destroy most of the site and, with it, businesses, homes and community”.

They have offered an alternative vision as part of the Metsä Wood ‘City above the City’ competition. Their idea is for the existing residential blocks are extended upwards, using Metsä’s Kerto-Q and Kerto-S LVL wooden modules, “while new blocks sitting on the podium itself use the same system.”

The timber would protected from the elements but visible through an aluminium-glazed screen. It would be exposed throughout the residential interiors.

Explaining their vision, they said: “London has a housing crisis but tackling this should not come at the expense of quality of life and the destruction of diverse and functioning communities. Our proposal seeks a sustainable future: environmentally and socially, for everyone, by building on the existing structure and community.

“We should address the difficult, but responsible challenge of augmenting the new with the old - both physical and social.

“This system could be adapted and replicated across London and other cities, as a way to address the tide of wholesale gentrification – a more human, slower paced and responsible method of regeneration and change, while adding significant density to the areas people want to live.”

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