laminated posts

Started by Dad75855, September 26, 2013, 09:42:55 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Dad75855

Hello. I am building a small cabin 24 x 32. The plans I have call for 6x6 poles, it is a pole framed structure. My question is this.
I have a plethora of good ground contact treated 4x4's in the barn. Can I simply add to them a 2x4, and a 2x6 glue and screws? Turning them into 6x6's. I have done this with 2x6's in the past to make beams, but never attempted it with 4x4's. Though I believe it should work the same. Just looking for a good second...and third opinion.
Thanks for your replies in advance.

North East Texas.

MountainDon

 w* Dad

I have seen engineering on pole barns constructed with laminated poles. However, the words "ground contact" caught my attention. Ground contact means, in the world of PT wood, on the ground, not in the ground.  There are PT woods that are foundation grade and those are suitable for burial.

The common glues we use are not the same as the glues and adhesives used under high pressures when factories laminate lumber. It is probably not worth the effort to glue these. Screws, well it depends on the screws. If they are rated as a structural screw, okay. The screws most of us use for everyday things are not suitable to a structural purpose. Nothing wrong with clamping and then nailing with a nail suitable for the PT wood.

G/L
Just because something has been done and has not failed, doesn't mean it is good design.


Don_P

It is not the same as a 6x6. The bending/buckling strength will be lower than a solid post because the joints can slip. There is a section on built up columns in Wood Structural Design Data on the awc.org website.

Squirl

Along the same lines as Mountaindon, it is hard to find 2x4s and 2x6s treated to the same level as the 4x4s at the big box stores.
It would probably be cheaper just to buy the 6x6 too.

Dad75855

All good points. I always like to use, re-use, and up-cycle material. However I won't sacrifice quality for cost. Thanks for the replies guys, looks like I need to get some 6x6's, and save the 4x's for something else.