CLT Creates New Opportunities For Hardwoods

The latest UNECE Forest Products Annual Market Review highlights the rapid growth in the market for cross laminated timber (CLT) and the new opportunities the product creates for wood, including hardwood, to compete in high-end structural applications. Although the first CLT production facilities were constructed in the DACH countries (Germany, Austria and Switzerland) in 1994, the full potential is only now being realized following a long period of technical and market development.

CLT first entered the building market during the 2005 to 2010 period, transforming from a small-scale niche product into large-scale industrial production. CLT panels consist of several layers of structural lumber boards stacked crosswise (typically at 90 degrees) and glued together on their wide faces and, sometimes, on the narrow faces as well. In special configurations, consecutive layers may be placed in the same direction to obtain specific structural characteristics. CLT products are usually fabricated with three to seven layers, but with additional layers in some cases.

Thickness of individual lumber pieces typically varies from 16 mm to 51 mm and width varies from 60 mm to 240 mm. Boards are finger-jointed using structural adhesive. Lumber is visually-graded or machine stress rated and is kiln dried. Panel sizes vary by manufacturer; typical widths are 0.6m, 1.2m, and3 m, while length can be up to 18m and thickness up to 508 mm.

The dimensions and lay-up of CLT production are now internationally standardized and recognized, and production techniques are optimized in modern manufacturing facilities. CLT is designed to maximize yield, utilize lower grades of lumber, and it can be made in a high volume of very large sections.

The result is a light but very strong panel product that can be made off-site and erected quickly to form structural walls, floors and ceilings. CLT is used in a wide range of applications in single-family houses, multi-story towers, public buildings and specialty construction.

From FORDAQ: fordaq.com.