Laminated Timber Beams
Laminated Timber Beams
(OP)
Hi All,
I have a question regarding building a built-up timber beam out of 2x12
We have spec'd solid sam members and they cannot get them in time.
The code has tables for 5-ply built-up sections but does anyone see any reason why a 6-ply would be a problem? Need it for capacity.
As an alternate I could try 2 4-ply built-up beams. Make the 4-ply beams with nails per the code, them thru bolt the two built-up beams together to get a new huge beam??
Thoughts?
I have a question regarding building a built-up timber beam out of 2x12
We have spec'd solid sam members and they cannot get them in time.
The code has tables for 5-ply built-up sections but does anyone see any reason why a 6-ply would be a problem? Need it for capacity.
As an alternate I could try 2 4-ply built-up beams. Make the 4-ply beams with nails per the code, them thru bolt the two built-up beams together to get a new huge beam??
Thoughts?






RE: Laminated Timber Beams
RE: Laminated Timber Beams
6 plys is not out of the question. But it does beg the question, why not engineered lumber like LSL or LVL. It would likely be much easier in the end.
RE: Laminated Timber Beams
The application is an exterior rehabilitation of an existing facility and not for a residential building. The existing structure is all old creosote treated large timber products. Not too sure I should be using LVL outside in the elements, but pressure treated DFL should be fine.
The member would be loaded onto by a nail laminated deck which would extend fully over the built-up beams so not asking the nails in the built-up to pull to all the ply's from a face mounted hanger.
RE: Laminated Timber Beams
Stainless steel or hot-dipped galvanized bolts (not sure if HDG bolts even exist).
LVL and LSL do not have approved exterior grades, but there is a Parallam Plus product that is approved for outdoor use.
RE: Laminated Timber Beams
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Laminated Timber Beams
I should think that what you want to do with the 6-ply treated DFL would be o.k., since it is uniformly top loaded. But, a couple things you might consider: 1.) cover the top with a piece of rubberized peal-n-stick flashing material to keep any water out from btwn. the plys; 2.) maybe consider using some of the newer structural screws from both sides, of the proper length 8" +, otherwise you are going to have a pin cushion of a beam. The screws will likely pull the whole beam together better after some initial build-up nailing. Apply a few more screws out at each bearing end just to help tie thing together.; 3.) have someone clean up the bearing ends so you actually have more than 2-2x’s bearing.
RE: Laminated Timber Beams
All in line with what I was thinking. A few great ideas like the peel and stick!
Thanks
RE: Laminated Timber Beams