With over 90% of single-family residences composed of light-wood framing materials, a large bias towards wood construction exists in the North American market. While traditional light-wood framing construction is only applicable to single-family homes and small-scale commercial buildings, the Wood Innovation and Design Centre (WIDC) (Figure 13.1) has demonstrated the feasibility of mass timber (MT) to build higher and provide a unique value proposition over conventional construction typologies.

FIG 13.1 Wood Innovation and Design Centre, Prince George, British Columbia by Michael Green Architects (2014). Layered CLT floor slabs create service zones unobstructed by downstand glulam beams to this mid-rise timber hybrid.

In North America, very little value is placed on the environmental benefits of using mass timber, and the top three decision-making criteria for the design of a project are typically costs, general performance criteria, and availability. Solid wood panels simply cannot compete with the value or air between studs in light-wood framing. This has shifted focus for mass timber in North America towards large-scale multi-family residential and office projects, driving expertise in larger on average projects than typically seen in other markets.

A single unified product standard PRG-320, published by the American National Standards Institute and APA (The Engineered Wood Association), exists for CLT to ensure all manufacturers adhere to the same panel production quality control requirements for inclusion in the building code. This standard is relatively rigorous in terms of glue bonding capability and is such that CLT panels produced in a vacuum press cannot pass the quality standard. As a result, small to mid-size CLT players as well as offshore groups have significant barriers to implementing their non-conforming products to projects in North America.

The early development and inclusion of these standards for stringent quality control has allowed code officials to revise building codes in both Canada and US to allow up to 12 and 18 storeys respectively for mass timber buildings in each country. This unified standard and code development has signalled a clear path for an all-out revolution in the construction industry for mass timber structures to be become a standardised staple of modern construction. There is much speculation throughout North America that the cost-driven environment paired with simplified and unified building code systems will allow mass timber construction to flourish and possibly pass volumes currently undertaken in Europe over the next five to ten years.