CLT Training Development at NWCI
In mid-August, Northwest Carpenter’s Institute of Washington (NWCI) held an eight-hour Introduction to Cross Laminated Timber (CLT) for RDF Builders at the Kent training center. The training was held online and in small groups of on-ground coursework to meet the training center COVID-19 protocol.
CLT was first developed in the early 1990s in Austria with usage in residential construction more common throughout Europe in the 2000s. While CLT has made residential construction more sustainable in Europe it hasn’t yet been able to compete with residential stick-frame construction in the U.S. In the 2010s, CLT grew in popularity in the U.S. as a substitute for concrete and steel. The advantages of mass timber include reducing carbon emissions and performing well in instances of fire (.pdf) and earthquakes.
In the past, U.S. builders have opted for concrete and steel. The production of CLT in the Pacific Northwest would give the region an opportunity for job creation in idle sawmills. With the growing interest in CLT and after the success of the eight-hour contractor-requested introduction course, NWCI is working to expand its CLT training. Staff are looking to offer the course once a month for membership and develop a more extensive, 24-hour CLT training next year. The training will feature greater detail on code revisions, especially fire code.
How is CLT made?
- Lumber boards are kiln-dried and trimmed
- Boards are stacked in layers crosswise and glued together, each layer facing against the grain of the layer adjacent
- Stacking boards together creates large slabs of wood that match or exceed the performance of concrete and steel
- Resulting in materials that can build entire buildings, like the tallest mass timber structure that’s 18 stories and over 280 feet in Norway