If the recent experiments in building with engineered wood are an indicator of the future, we may soon be able to bid goodbye to concrete and steel structures. Cross Laminated Timber or CLT as it is commonly referred to, is an engineered timber product with good structural properties and low environmental impact (where sustainably sourced timber is used).
Invented in Europe in the 1990s, it has been extensively used for low-rise buildings across UK, Germany, Holland and other countries. The recent years have seen this product cross over to North America and to the south to Australia.
Today, CLT is promoted as the green choice for schools, health care facilities, public buildings, commercial buildings and multi-family housing because of its cross-layered construction, reduced carbon footprint, and ready to assemble system. The CLT panels are a state-of-the-art solid cross laminated timber panels, ideal for floor, wall and roof systems.
CLT : The new wood on the block
CLT is an engineered wood panel typically consisting of three, five or seven layers of dimensional spruce lumber. Kiln-dried boards are layered perpendicular to one another and then glued. This cross lamination provides dimensional stability, strength and rigidity.
Most manufacturers use formaldehyde-free interior/exterior polyurethane (PUR) adhesives. Boards are face-glued and then pressed, planed and sanded into panels. Using CNC machinery, panels can be custom fabricated to create openings, compound angles and unique features requiring complex geometry to meet specific end-use applications.
A highly versatile material
CLT panels resist high racking and compressive forces making them cost effective for multi-storey and long-span diaphragm applications. They weigh less than concrete or steel, so can also reduce foundation costs. CLT elements can be combined with other building materials enabling flexibility in design, style and finish of architecture.
Usually manufactured for specific applications, CLT panels are prefabricated and shipped directly to the job site, where they can be quickly and efficiently lifted into place. Architects and engineers are today exploring possibilities of building high-rise structures of 9-storeys and upwards with CLT.