While timber has been used as a building material for millennia, modern engineering allows wood to be stronger and more durable than ever before. Around the world, we can see ‘timber towers’ rising up in our cities as architects and city planners seek to build sustainable buildings which will help reduce carbon emissions.
Innovation
The ultimate building material
Engineered woods
This is an innovation of materials which means that timber can replace energy intensive materials such as concrete and steel. One of the most commonly referred to innovations is cross laminated timber (CLT), which has been the basis for these ‘timber towers’, however there are many other forms of this engineers wood, such as glulam or oriented strand board (OSB).
By using more timber in our built environment, we help ensure that the modern world is built without the pollution or carbon emitting materials favoured in the 20th Century. Innovation in timber, such as engineered or modified woods, help make this a reality.
What are engineered woods
Engineered woods may also be called ‘mass timber’ or ‘composite wood’, which essentially means that the wood has had its properties modified in order to give the timber added strength. These products are engineered to precise specifications, and often will be cut to measure offsite before being transported and erected at great speed.
While the process for creating these hardwoods will vary, the way these timbers are created is often by recombining either softwoods or hardwoods and using both heat, pressure and adhesives bring them back together with new attributes. By layering the wood in unique ways so that the grain of the wood runs against each other you can massively increase the strength of the timber.
Advantages of engineered woods
As these woods are being engineered, they can be designed to meet very specific performance requirements or needs, while retaining many of the advantages of solid wood. While they can still be easily reworked with ordinary tools and basic skills and sequester carbon, some engineered woods, such as CLT and glulam, are pound for pound stronger than steel.
Engineered timber can also be made from small pieces of wood, wood that has defects, or species which aren’t otherwise able to offer a commercial use. This adds additional efficiency into the timber supply chain. Offsite construction using engineered products means buildings can be completed quicker, quieter, and cleaner with minimum disturbance to communities.
Building tall with timber
As sustainable construction becomes more important, timber has been growing in popularity, and over the last 15 years, growing in height. Timber skyscrapers are being constructed around the world using engineered timber.
The UK were early leaders in constructing these timber towers with Waugh Thistleton and Hackney Council building a 29m, nine-story, apartment building in Murray Grove in just 49 weeks. This has become a world renowned example of timber construction.
Since then, building with timber has taken off globally. Hackney Council adopted a ‘wood first’ policy, which has seen timber take off – quite literally – in the neighbourhood, with more than half a dozen award winning buildings now completed.
From Sweden to Canada and all the way down to Australia, many countries can now boast of their own multi-level timber buildings. By selecting timber, a less energy intensive materials than concrete or steel, these projects are helping reduce carbon emissions.
As of 2020, the tallest timber frame building in the world is in central Norway with Mjøstårnet, which is 280-foot-tall or 18 stories high, and is constructed entirely of Glulam and CLT by Moelven.
