Carbon footprint counts! Using wood reduces carbon footprint: As trees grow, they absorb carbon dioxide and release oxygen. Manufactured wood products retain 50% of their carbon (dry weight), and wood products require less energy to manufacture than many other products.
The ability to go higher with wood opens opportunities for cost savings. CLT is lighter than steel and concrete systems, and thus requires smaller foundations. Lighter buildings help reduce cost impact when challenged with poor soil conditions. Trends are showing higher rental rates for more organic spaces.
CLT goes up quickly. CLT walls are prefabricated in a factory, allowing higher quality construction, lower build time and less time on site.
CLT is visually stimulating. Research says wood environments are comforting and lower stimulation for the occupants.
Feel and Function
Some of the best buildings to use CLT include multi-family and hospitality units, due to the repetitive nature of design. CLT can be used with beams and columns to provide an open floor plan for office use. Mixing CLT with more traditional systems can overcome building height restrictions by saving floor-to-floor height.
CLT has been tested and shown to be able to meet the highest fire-rating requirements. The large profile of the wood makes it hard to start burning. Wood’s char layer insulates its core from burning through quickly, which allows for predictable fire behavior.
CLT’s mass and multi-directional strength provide resiliency in hurricane, tornado and blast applications.
Current codes allow up to five stories of wood over concrete podiums. CLT is currently referenced in the IBC and wood design standards for 2015 and onward. Ongoing research indicates the possibilities of wood structures to be built up to 24 stories. Seismic and fire testing are the focal points of research in order to achieve greater heights, but CLT holds enormous potential in these areas. Watch out for the 2021 IBC for the biggest changes.