Building Fast with Mass Timber
Why wood? As cited by the Canadian Wood Council and backed up by their numerous case studies, “wood is renewable, versatile, meets code, and costs less." Significant efforts by the CWC have resulted in a growing awareness and demand for the utilization of wood in modern building construction. Changes to the BC Building Code in 2009 and the expected changes (2015) to the National Building Code of Canada are resulting in increased wood use in mid-rise construction. The BC Wood First Act, implemented in 2009, has also contributed to an increased demand for using more wood for all publicly-funded buildings in BC.
Why mass timber? Multiple studies in the last two years have shown that the construction cost of a well-designed mass timber building is very close to the cost of a concrete or steel building – generally within +/- 3-5% on total construction cost – and often greatly increases the speed of construction, by up to 20-30%.
On our own Surrey Christian School – a 20,000 sqft building comprising FLT on Glulam beams and columns – the 2-storey superstructure was fully erected, including shear walls, in 4.5 days. In addition to the reduced costs and construction time, there is the benefit of structural efficiency - a mass timber building can be up to 75% lighter than a concrete building, reducing foundation sizes and easing handling of materials.
Some examples of timber projects across the world and their construction times are below. For more details on many of the projects, refer to the excellent Survey of International Tall Wood Buildings put out by FII earlier this year. Note not all erection times are directly comparable due to the widely varying building types included.
|Project & Location||Stories||Floor Structure||Vertical Structure||GFA||Timber Erection||Erection Speed|
|Surrey Christian School||2||NLT||Glulam Post + Beam||21500sqft||4.5 days||4780 sqft/day|
|Svartlamoen, Trondheim, Norway||5||CLT||CLT Walls + Cores||23200sqft||10 days||2320 sqft/day|
|LCT One, Austria||8||NLT concrete composite||Concrete Core, Glulam Post + Beam||17200sqft||8 days||2150 sqft/day|
|Wohnanlage Wagramerstrasse, Vienna||7||CLT||Concrete Core, CLT exterior walls||90800sqft||50 days||1820 sqft/day|
|Limnologen, Sweden||8||CLT||CLT Core, Glulam Post + Beam||115200sqft||80 days||1440 sqft/day|
|3xGrun, Berlin||5||CLT||Glulam Post / LVL Beam||31200sqft||25 days||1250 sqft/day|
|Cenni di Cambiamento, Milan||9||CLT||CLT Walls + Cores||183000sqft||150 days||1220 sqft/day|
|Holz8||8||CLT||Concrete Core, CLT exterior walls||18700sqft||16 days||1170 sqft/day|
|Stadhaus, London||9||CLT||CLT Walls + Cores||25300sqft||24 days||1050 sqft/day|
|Forte, Melbourne||10||CLT||CLT Walls + Cores||31100sqft||30 days||1040 sqft/day|
|UBC Earth Sciences, Vancouver||5||LSL / CLT||Glulam Post + Beam||170000sqft||180 days||940 sqft/day|
|MEC Headquarters||4||NLT||Glulam Post + Beam||111900sqft||120 days||930 sqft/day|
|Centre for Interactive Research on Sustainability, UBC, Vancouver||4||NLT||Glulam Post + Beam||61100sqft||80 days||760 sqft/day|
|Bridport House, London||8||CLT||CLT Walls + Cores||45400sqft||60 days||760 sqft/day|
|Wood Innovation and Design Centre||6||CLT||CLT + Glulam Post + Beam||49000sqft||100 days||490 sqft/day|
|E3, Berlin||7||NLT concrete composite||Glulam Post + Beam||13700sqft||40 days||340 sqft/day|