Posted in Architects
Today’s Building Codes Recognize Wood’s Capabilities
Developments in wood science and the subsequent advancement of building codes are creating opportunities for novel design solutions and expanding the range of structural applications for sawn lumber and engineered wood products. Applications for wood in construction span the technological spectrum, from traditional light framing approaches to innovative mass timber high-rise building design.
The 2012 International Building Code (IBC) regulates allowable building height based on the combustibility of structural framing materials and fire resistance ratings of the walls, floors and roof structure. With increased code recognition for fire sprinklers and other fire safety building features, the size and height of wood buildings that are allowable have increased dramatically.
The IBC permits low-rise business and mercantile buildings of wood construction to be unlimited in area if they have reasonable separation distance from other buildings, along with a fire sprinkler system. Residential buildings can be taller than in the past, and wood features in otherwise non-combustible buildings are more readily permitted. The less-restrictive 2012 IBC codes are dovetailing with new developments in wood technology along with the emerging acceptance of wood as an affordable and renewable building material to set the stage for an increase in wood use in a number of building types.
Wood continues to be a lower cost alternative to steel and concrete structures, and as codes evolve to reflect innovations in materials science, new opportunities arise to construct more economical buildings in traditionally steel and concrete project types. Architects for the nine-story Stadthaus wood apartment building in England found that, comparable to concrete, a wood building offered cost savings of more than 15 percent, and that 186 tons of carbon were sequestered within its structure.
Concrete and steel have a large carbon footprint and are highly energy intensive materials to produce. Wood, in contrast, has a unique carbon profile. When harvested sustainably, using wood systems in lieu of concrete and steel reduces initial embodied energy and global warming potential of the materials in a building. A forest, if managed properly, is a large carbon reservoir. When a tree from the forest is manufactured into a building product, this carbon is sequestered for the material’s life cycle. Wood has long been a favorite among craftsmen for its combination of workability and strength. These characteristics also make it perfect for milling with computer numerical control (CNC) machines. Because of this, both engineered wood products and sawn lumber are ideal for a digitally manufactured component approach to building construction. The adoption of direct to fabrication workflows makes once prohibitively expensive traditional joinery or complex geometric forms achievable and economical.
As a result of advances in materials science and technology, the options for using wood in construction are rapidly expanding, and building codes are adapting in response. These code and technological transformations are resulting in opportunities to expand the use of wood in many project types typically the domain of concrete and steel. ■
To learn more about the benefits of wood, visit reThink Wood here.
This information and the websites identified above are provided solely as a convenience to the reader. They are not intended to state or imply that the editors of Engineered Wood or LP Building Products sponsor, recommend, endorse or are affiliated or associated with the companies or products listed.