Timber frame mid-rise buildings offer cities the ability to increase density more cost-effective buildings while also achieving a lower carbon footprint that steel and concrete construction. As we develop actions as a City in response to the declaration of a ‘climate change emergency’, timber frame buildings emerge as an important consideration.
As noted in an article by ReNew Canada, timber construction is one such material that is undergoing a revival globally, and is demonstrating its potential in a range of situations. In Canada, some of the best examples of timber construction can be seen in British Columbia. For instance, the Brock Commons at the University of British Columbia, at 18 storeys, was the tallest timber structure in the world in 2017. It used what’s being dubbed “mass timber” or “tall wood” construction, which makes use of sustainable engineered wood products including cross-laminated timber (CLT) and glulam.
The Ontario Ministry of Natural Resources has released a Tall Wood Building reference for construction of wood buildings up to six storeys, and an amendment to the National Building Code allowing for even taller wood structures is expected in 2020.
Using current mass timber construction practices for buildings up to six storeys offers a number of benefits:
Wood is a green building material. Wood is a renewable resource that can be locally sourced. The production of CLT produces fewer greenhouse gas emissions and less air and water pollution that other building materials.
Many will remember the midtown fire that started in a woodframe building under construction. Mass timber building products are tested for flammability. CLT, for example, must demonstrate a two-hour fire resistance rating in order to meet American Society for Testing Materials standards.
Mass timber buildings are cost-effective and can be constructed quickly (limiting disruption to the neighbourhood). Most importantly, wood performs better than most building materials over the lifetime of the building, resulting in potentially reduced maintenance costs.
Exposed wood has also been seen to lower stress and blood pressure and offer psychological benefits.
We can expect to see more mass timber structures being built in Kingston as local builders seek to enjoy these benefits and these fire-resistant wood products become more available in Ontario and will continue to monitor the national movement toward mass timbre and any legislative changes that may be coming forward in the near future.