Glulams Questions & Answers
FAQs - Technical & Installation
Glu-Lam Sales Co.has the answers to your questions!
The “24F” stands for a 2,400 psi bending stress. The “V” stands for “visually graded,” and the “4” identifies the specific layup of the wood layers. It is the industry standard for most residential structural applications.
An Unbalanced beam is for simple spans (two supports). A Balanced beam is designed for continuous spans or cantilevers where the “top” of the beam might experience tension.
24F Denotes a Douglas Fir Glulam Beam and 20f Denotes an Alaskan Yellow Cedar Glued Laminated Beam.
No, Alaskan Yellow Cedar Glu-lam beams of the same size are actually less strong. Consult your Structural Engineer or Architect for specifics.
Even if a beam is balanced, the manufacturer often stamps a “TOP” to help the installer keep the beam plumb and aligned with the 3 architectural grade (sanded sides) if applicable.
On an Unbalanced beam, the bottom contains the highest-strength wood. Installing it upside down can reduce the beam’s capacity by up to 50%. Always look for the “TOP” stamp.
Yes, but you must specify this when ordering. You will need a “Balanced” layup (24f-V8) because the tension switches from the bottom of the beam to the top at the overhang.
FAQs - Maintenance & Job Site Care
Use your best judgement, but often installers will keep it wrapped until they are ready to install. If the wrap gets water trapped inside, slit the bottom to let it drain, but keep the top covered to prevent “sun-tanning” (UV discoloration).
Yes. A medium-grit sandpaper (80–100 grit) will usually remove most surface dirt or scuffs. Sand in the direction of the grain to avoid swirl marks.
The end-grain will absorb moisture faster than the rest of the beam, which can lead to “swelling” or deep cracks (checks) at the end of the beam. Always re-seal any cut ends.
No. Power washing can “fuzz” the wood fibers and drive moisture deep into the laminations. Stick to a broom, a damp rag, or light sanding.
Our beams use ultra-low emitting moisture-resistant adhesives that often meet or exceed all “green” building standards (like LEED).
Yes. Douglas-fir Glued-Laminated beams can be used for basement headers. Just ensure there is a moisture barrier between the wood and any concrete or masonry surfaces.
You want “Framing” or “Industrial” grade. These are structurally identical to the pretty ones but are not sanded and may have knots/voids, saving you money on parts that will be behind drywall.
FAQs - Comparison & Selection
PSL is very strong, but glulam is generally more cost-effective and much more attractive for exposed applications. Glulams are also available in larger custom lengths and shapes.
LVL is very strong, but glulam much more attractive for exposed applications. Glulams are also available in larger custom lengths and shapes.
Glued-laminated beams are often considered more fire resistant than standard solid-sawn beams due to their dense construction. “1-Hire Fire Rated Construction” can be requested as a specialty Layup from the manufacturer.
Yes. Alaskan Yellow Cedar glulams are frequently used for pedestrian and light-vehicle bridges due to their incredible rot resistance and strength. Pressure Treated Douglas Fir is also used, but the individual use cases will determine which Pressure treating product.
Not necessarily. It is more naturally resistant to decay. This makes it a “green” alternative for those who want to try and avoid the chemicals found in pressure-treated lumber. Also, the dense wood fibers resist pressure treating.
Very rarely. Because they are made of thin, kiln-dried layers with alternating grain patterns, the “stresses” in the wood cancel each other out, keeping the beam straight.
Yes. However, glulam columns are manufactured with a different internal layup than beams to handle “axial” (vertical) loads. Always specify if you are ordering a column vs. a horizontal beam.
A glulam column is less likely to twist than a solid 6×6 or 8×8 timber. It’s the “straight and true” choice for high-end timber framing.
Yes, but due to the the high humidity it is encouraged to use Alaskan Yellow Cedar or Pressure Treated Douglas fir to protect against the moisture.
Yes. Coastal Douglas-fir is generally recognized as having higher strength properties, which is why most APA certified GLB manufacturers on the West coast use it.
FAQs - Logistics & Ordering
Yes, though anything over 50’ feet usually requires a specialty “stretch” trailer and may have different shipping rates depending on your location.
“Framing” is the lowest grade, as almost nothing is done to the finished beam, often used when fully concealed. “Framing” grade beams will often have “Skip” where the laminations overlap, glue is present across the beam and large voids may be present. “Industrial” grade only requires planning, possible filling of larger voids, and will minimize “Skip” and visible glue. Often used where the roof system will be painted or concealed.
“Architectural” Grade requires planing the beam to remove “Skip”, some sanding, filling medium sized voids with putty and less knots are allowed. “Architectural is the most common visual grade. “Premium” is the highest common grade, with less voids and knots allowed, even more planning and sanding and more time in the finish room. “Clear” grade is the highest visual quality, but less commonly ordered. Little to no knots are allowed, all voids are filled with clear inserts or disallowed completely during layup, and the beams are sanded even further. This is the highest visual grade and comes with an equivalent price factor due to the time and care required to produce these beams.
Yes, we provide simple Beam Tables for smaller orders, for larger custom or complex orders we provide shop drawings which include a Layout and Beam table, for your approval before we start the manufacturing process. For Glulams with fabrication our submittal will include profile and detail drawings as well.
Yes. While stock beams have a standard “flat” or “slight” camber, we can custom-manufacture beams with a specific radius to match your architectural plans.
We can provide documentation for Mixed Use FSC-certified Glu-laminated beams.
Yes. Architectural and Premium grades come with “eased” (slightly rounded) corners to prevent splintering and give a finished look.
They usually increase in 1-1/2″ increments (6″, 7-1/2″, 9″, 10-1/2″, etc.) to match the thickness of the individual wood layers.
We provide the direct insight, technical expertise, custom sizes, specifications and direct-from-mill quality that pros like you require to fulfill any size order, On-Time, Under Budget and To Spec.