Wood Species
The species of wood used to make glulam beams are Douglas Fir (most common), Alaskan Yellow Cedar*, Western Red Cedar*, Redwood*, Southern Yellow Pine.
* these beams can be specified in lieu of pressure treating. This may be necessary for indoor applications where pressure treatment is not desired, or outdoor locations where a special look is sought.
Shapes and Sizes
Glulam can be manufactured in almost any fashion that you can bend and ship wood. The maximum length of beams is only limited by the ability to ship them, without too much trouble beams can be 110 ft or so. Some common beams shapes are: straight, curved, Tudor aches. Curved work may require thinner laminations (1/2″ laminations rather than 1 1/2″ laminations) in order to create tight radius beams.
Glulam Appearance
The species of wood used to make glulam beams are Douglas Fir (most common), Alaskan Yellow Cedar*, Western Red Cedar*, Redwood*, Southern Yellow Pine.
* these beams can be specified in lieu of pressure treating. This may be necessary for indoor applications where pressure treatment is not desired, or outdoor locations where a special look is sought.
Please see APA-EWS Form No. Y110 and in ANSI A190.1 for more information; a summary is shown below:
Framing Appearance
Uses standard dimension lumber widths to create net width beams that are typically 3 1/2″ and 5 1/2″ wide. Low laminations, glue smear, end joint offsets and glue line squeezeout are acceptable. Knotholes splits, and wine is permitted. Voids are not filled and these beams should never be exposed to view. Framing appearance is also sometimes referred to as “Hit & Miss”.
Architectural Appearance
This is the most common beam specified for beams that will be exposed to view. Specifics are: Exposed knot holes and voids measuring over 3/4″ are filled with a wood-tone filler. Exposed surfaces will be sanded smooth and the bottom corners will be eased.
Other appearance options:
- Architectural and Premium grade beams can be ordered with “clear wood inserts” in lieu of putty filler at voids.
- Beams can have a “rough sawn” appearance
- Lumber can be hand selected to reduce knots for a “clear appearance”. Note that the laminations will still be visible, but each individual lamination will be of the highest quality available.
Industrial Appearance
Even though this is not an “architectural” appearance, this grade of beam is most often used in industrial or retail buildings and may be exposed to view, however the beam should not be regarded as a design feature as it in not intended for that purpose. Specifics are: Loose knots and knot holes appearing on the bottom of beam will be filled with putty, but voids appearing on the sides of the beam will not. Occasional planner “misses”, low laminations and wane are permitted.
Premium Appearance
This takes the architectural appearance on more step. Specifics are: All exposed knot holes and voids, ragardless of size, will be filled with a wood-tone filler. Exposed surfaces will be sanded smooth and the bottom corners will be eased.