LSL vs LVL

[theoldwizard1]

This came up in a different thread.

Laminated strand lumber vs laminated veneer lumber.

So what is the difference ?


Segue - When you look at OSB you have to wonder HOW CAN THEY CALL THAT "ORIENTED" strand board !

LSL are made in a very similar fashion to OSB with a few key differences. The chip/strands are of "better" quality and are much longer. The strands are laid done in a much more parallel fashion.

 

[nh_yota]

https://www.nishkian.com/understanding-engineered-wood-beam-options/

 

[LB-1911]

Laminated Veneer Lumber (LVL)
LVL is a widely used structural composite lumber product. It is produced by bonding thin wood veneers together in a large billet so that the grain of all veneers is parallel to the long direction. The LVL billet is then sawn to desired dimensions depending on the end-use application. Because LVL is made with scarfed or lapped jointed veneers, LVL is available in lengths far beyond conventional lumber lengths.

Popular LVL applications include headers and beams, hip and valley rafters, scaffold planking, and the flange material for prefabricated wood I-joists.

Parallel Strand Lumber (PSL)
PSL is manufactured from veneers clipped into long strands laid in parallel formation and bonded together with an adhesive to form the finished structural section. The length-to-thickness ratio of the strands in PSL is around 300. Like LVL and glulam, this product is used for beam and header applications where high bending strength is needed. PSL is also frequently used as load-bearing columns.

Laminated Strand Lumber (LSL)
Similar to PSL, laminated strand lumber is made from flaked wood strands that have a length-to-thickness ratio of approximately 150. Combined with an adhesive, the strands are oriented and formed into a large mat or billet and pressed. LSL is used in a variety of applications from studs to millwork components.

Oriented Strand Lumber (OSL)
Similar to LSL, oriented strand lumber is also made from flaked wood strands. The strand geometry for OSL results in length-to-thickness ratios of approximately 75. Combined with an adhesive, the strands are oriented and formed into a large mat or billet and pressed. OSL is used in a variety of applications from studs to millwork components.

Source
https://www.apawood.org/structural-composite-lumber

 

[ddawg16]

Here is a good explanation of all of the options/types

LVL is basically plywood....but the strands all run the same way.

I have a punch of PSL beams in my house and garage...….one thing I can say.....that **** does NOT flex. Extremely stable......and heavy.

https://www.apawood.org/structural-composite-lumber

edit....LB beat me by a few seconds

 

[matt_i]

The difference is cost LOL! They are all superior to typical SPF wood products. Each has engineering. LVLs seem to be the most prevalent (meaning stocked in many sizes with really exotic sizes by special order) in lumber yards around here.

The other ones are available but special order.

OSB is just a way to use trash wood trees to make plywood instead of having to peel veneers to make the same. It does help to utilize wood that would probably otherwise be wasted or goto paper mills lol, instead of having to cut down all of the giants.

 

[theoldwizard1]

Here is a good explanation of all of the options/types

LVL is basically plywood....but the strands all run the same way.

Yep, found a video ! I think the proper term would be "veneers" not "strands"

• Logs are cut into about 8.5' length and debarked.
• Soak in hot water (for easier peeling).
• Lathe "peels" the log to a 3.5mm thick veneer.
• Plies are cut to 10'-12' (?) length.
• First big difference from plywood. Only very small, tight knots allowed. NO VOID. (Like a grade A plywood face.)
• Veneers are dried to 5%.
• Second big difference from plywood. All veneers are laid in the same direction. No "cross". Maximum strength in only one direction.
• Glue is applied to the veneers.
• Third big difference from plywood. The plies are laid on top on each other in a staggered fashion so that there is a "scarf" joint running through the stack. (The assembly line is moving under the stacker.)
• The number of plies depends if they are making 2by or 4by (thicker ?) lumber.
• Pressed and heat.
• Some factories have presses that will handle lengths over 50'
• Sides trimmed, cut to desired width and length, stacked.