I’m going to be building a deck soon (25′ long x 15′ wide). I want to use a glue lam beam for the girder. I don’t know much about glu lam’s and was wondering if someone could tell me the sizes and thickness they come in and perhaps what thickness would be good for me to use for this size deck. I’ts a few feet off the ground and I figured I would use three footings for the 25′ girder (6×6 posts for support). Thanks.
Les
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Replies
I'd be thinkin of a triple 2x12 my self..a heckuva lot cheaper, and glulams ain't PT, and could easily DE-LAM in the weather.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
You can get gluelams in PY ( or used to be able to) but LVLs are easier and cheaper and can be PT too.
For the engineering, the retailer that supplies them can do that based on a scetch with all the span info.
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>> I'd be thinkin of a triple 2x12 my self..a heckuva lot cheaper ...
Depends on what your time is worth, or what you'd rather do with your time. I've made up beams out of 2x12s, and I didn't like it.
>> ... glulams ain't PT, and could easily DE-LAM in the weather.
I have no personal knowledge, but according to an article I read in a 12 or 15 year old FHB, pressure treated glue lams are available.
My guess would be Lester is working solo.
A 25' 4x16 would be pretty heavy. Another reason why I like built up.
Jon Blakemore
Or... since it's only a few feet off the ground add a few more footers and reduce the size (and cost) substantially. For example, go with 6 footers (5' span between footers) and a 4x6 will probably to the job. You can use the Excel program at http://www.wwpa.org/techguide/suite.htm to confirm that your design will meet common engineering requirements for sheer, bending etc.
Lester,
I have to agree with Sphere. The only reason you would need a glulam is for appearance. Since you're deck is almost ground level, only the rodents would appreciate the material.
I would recommend 4 footings with 3 2x12's. If you have a 1' cantilever on each end, you would have a beam span of about 7'. 3 footings would make for a beam that is a little long.
Jon Blakemore
Big bucks and they'll de-lam in the weather...
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"I want to use a glue lam beam for the girder. "
Why?
Jeff
Buck Construction, llc Pittsburgh,PA
Artistry in Carpentry
About all I know about them is if they ain't PT they act like sponges.
A glulam is a waste under a deck. It will start to decay too soon. For your application you can probably use a 6x8 DF#1 PT supported at the ends and two mid points, or a 6x10 DF#1 PT or 6x12 DF#2 PT supported at the ends and one mid point... a foot or two of beam cantilever at either end in any case. That's according to engineered plans for a deck sitting in front of me, so your mileage may vary.
6x would work if he can get it locally. I cannot get anything like that around here unless it's special order.
If Rez would get him to fill out his profile we could find out where he is located <g>
Jon Blakemore
6x is preferable to the 3 2x sandwich because water will get in between the layers of 2x... plus no need to bolt it together
But on a low deck he doesn't need a 6x beam. Just add more posts.
Every post requires a pier. Just depends on whether you'd rather dig more holes and pour more concrete, or buy a bigger beam.
Hey, please enlighten us w/ your trib. span, cant. (if any), o/c spacing of joists. I can run #'s for you then. As the others said...the glue-lam would need PT(which can still be done)..but is costly.
Tony
Hey all,
Thanks for all the replies, I was away for the holiday and this is my first visit back since the post. Basically, I wanted to use a glulam for the girder and the end joist because I was told they are very true and straight and I didn't want to have to build up a multiple 2x10's to make up the 25' length. I know they are more expensive, but for the money the timbertech is costing, a few more dollars isn't going to kill me. Have a buddy out West that swears by glulams so figured I'd give it a shot.
Les