Glulam hard?

[snickar_lasse]

hi! every time I nail into a glulam, I think, how the heeee can it be so hard? regular wood isn’t as hard.

 

[Plupp 23608]

"Regular wood" does not have the same quality class. A fine unmarked plank is roughly C12, whereas a glulam beam is C30 if it is homogeneous. If it is a combined glulam, it usually has C18 in the middle and C30 in the outer sixths of the beam's height. The glue that penetrates the wood during manufacturing, and the fact that the wood is drier (about 12% moisture content upon delivery) than a regular plank, likely also affects how it is to nail into.

 

[snickar_lasse]

hello Acme! thank you. it sounded complicated. T and K I know, but not C. have you read on Wikipedia?

 

[jon_h]

C is about to replace K. I believe it's just a matter of swapping K with C, except for K12 which corresponds to C14.

 

[saturnus]

hi! every time I nail into a glulam, I think, how the heeeck can it be so hard? regular wood is not as hard.

I suppose you manage to hit a knot every time

 

[Plupp 23608]

Hello Acme! Thank you. That sounded complicated. I know T and K, but not C. Have you read on Wikipedia?

C is the European standard and K is the Swedish one. I don't quite dare to trust Wikipedia.

 

[Bob_the_builder]

Well, Jon is right that it's "just" a matter of changing the letter. As usual in these contexts, it takes about a generation of building material dealers before new designations catch on. When was the inch abandoned as a unit of measurement for nails and timber...?

C24=K24=T2
C18=K18=T1
C14=K12=T0

T indicates that the timber is sorted manually and thus not machine-tested.

For glued laminated timber, the letter L is used, where L40 is what's typically available for purchase.