Glulams vs Solid Wood Beams

There are pros and cons of using solid sawn beams versus glue laminated timber.

The pro of solid sawn timber beams is that the they have the true beauty of natural wood. They are strong, easy to work and get better looking as they age. There are limitations though. Natural wood beams will shrink and check (some people love that look while others don’t) and while they are strong, they have limits as to how far they can span and how much load they can hold. Wood beams can have curves cut into them, but the timber will be weakened structurally and care has to be taken to leave enough continuous grain. These limitations are considered beautiful and are desired by many clients and interior designers, but for people who do not care for the checking, or who want long graceful curved beams, glulam timbers are an option.

Glulam beams are made of many thin boards that are glued together. A typical natural wood beam is six inches by eight inches, a large solid wood beam can be 12″x20″. Glulam beams can be up to 54″ thick by gluing thirty six 1 1/2″ plies together – that makes them incredibly strong. The plies can also be finger jointed together lengthwise so glulam beams can be over one hundred feet long. Glulam beams can span great distances and carry enormous loads. They can also be curved. Because a plies are thin, they can be layered and bent in presses to achieve curved beams of great strength. Another advantage of glulam beams is that they are made from kiln dried material so checking is reduced. The main disadvantage of glulam beams is the look. The laminations are distinct and can be seen unless a dark stain is used. Glulam beams with many plies don’t look natural and they don’t have the feel of a natural timber frame. Glulam beams look contemporary, which can be architecturally perfect for one project and completely wrong architecturally for another project.

In the end, choosing glulam vs timber comes down to the look that is desired and the structural requirements of that look. People who like the look of natural timber frames may have to limit their designs to short spans without long curved beams. People who want great spans and long graceful arches will need to enjoy the contemporary look of glulaminated beams.