Glulam vs construction timber

[gdsaren]

anyone who knows the difference in load-bearing capacity between 90x90 glulam versus 2 screw-laminated 45x95 that will be used as posts for a shed with raw board + felt roof?

 

[Dan_Johansson]

Is it the difference that's interesting, or "if it works"?

If you want to know if it works, you should probably add more information about how big it's supposed to be and how many posts are intended...

 

[Rabbithole]

2 screw-glued 45x95 should become slightly stronger as it becomes 90x95 compared to 90x90 if it is well glued and the correct wood grade, but either way, a little. There is also sawn 90x90/95x95.

 

[justusandersson]

The question has several answers. The formal answer is the glulam column because it has a higher verified modulus of elasticity, which compensates for the slightly smaller moment of inertia (in the weak direction). The informal answer is that they are quite equivalent if you use C 24 wood for the glued laminated post.

 

[OTTO_75]

Borrowing the thread for a follow-up question...
What difference does it make to glue-screw or just screw for the answer?

 

[justusandersson]

A lot! Gluing is necessary for the column/beam to be treated as a homogeneous piece. Without glue, the result will be flexible.

 

[Leif i Skåne]

The difference is that glulam beams consist of small parts with growth rings at different angles and are finger-jointed lengthwise to remove larger knots. They are somewhat more dimensionally stable than C24 timber. But 2 pieces of 45x90 together will do just fine.