Understanding Mass Timber – PLT, CLT, GLT and LVL

Mass timber is a term that covers a range of timber products and represents a relatively new approach to both residential and commercial building in New Zealand.

Unlike traditional light-frame construction (timber frames and joists – NZS3604 method), which are primarily nailed together and assembled onsite over multiple days, mass timber is generally manufactured off-site and is typically lifted into place within hours of arriving onsite. Key building components can include large, solid wood panels, columns or beams, forming load bearing walls, floors, and roofs.

But what is the difference between these products?

New Zealand has a number of manufacturers who are creating products that fit within the mass timber category. At Woodspan, we manufacture PLT and Glulam (or GLT), but there are other forms of mass timber such as CLT and LVL. Check out our comparison below along with a description which explores the key differences between these products.

Parallel Laminated Timber (or PLT) has timber laminates which are glued together with the grain all running in the same direction. Panels are generally 4-6m long and 890mm wide. Manufactured and cut to fit your project. Typically used for floors, mezzanines and roofs.
Cross Laminated (CLT) Timber has laminates that are glued together in layers (usually 3, 5 or 7), with the grain in each layer running at right angles to the adjacent layer. Typically used for floors, walls and roofs.
Glue Laminated Timber (GLT) or Glulam is constructed similar to PLT, but formed into beams or posts. Perfect for bearers, joists, posts, lintels, rafters, beams and balustrades – often with a visual grade finish.
Laminated Veneer Lumber (LVL)is made by peeling wood veneers and laminating them together, resulting in a very consistent and strong building material. Typically used for columns, joists, lintels and rafters.

If you want to explore mass timber solutions in more detail and find the best solution for your next project, get in touch with the Woodspan team to see how our PLT and GLT products can work in your next build.

Learn more about PLT here or Glulam here.