29 May 2018
Creative and stunning: Tall timber buildings’ rising profile
High rise timber buildings are becoming more common around the world. A global wave of new buildings, more radical building proposals and research using engineered timber has resulted in 40 such buildings that are completed, under construction or planned.
Engineered wood such as glulam and CLT can provide structural integrity and fire resistance that is superior to conventional ‘platform’ timber frame construction and comparable to those provided by materials that most skyscrapers are made of – concrete and steel.
Significant obstacles remain, however. Many local building regulations and fire codes prohibit the construction of wood structures above five or six storeys. But the local codes are still based on platform timber construction and have not yet all caught up with the development of engineered timber, which can demonstrate fire performance comparable to concrete and superior to steel.
Another significant obstacle is the lack of standardisation of construction materials, methods and definitions. There are many different types of engineered timber and a large degree of variance when it comes to constructing tall timber structures. Often it is the location and orientation of steel connectors between the timber elements that govern how long a structure can withstand fire or how much seismic movement it can take.
Most mass timber buildings use a combination of timber, steel and concrete, with timber relating to only the primary structural system such as the core, floor beams or horizontal trusses, and vertical columns. Many rely on a concrete core or concrete slabs in order to provide stability and fire protection that will satisfy local codes.