Sizing a beam for structure on piers
PenobscotMan
| Posted in Construction Techniques on
Can anyone give me a reference to an up to date table for sizing beams for a structure on piers? By piers I mean sonotubes supporting 6X6 posts supporting beams supporting joists. Like a deck. But a house.
Replies
Where I am, if the beam is to be steel, my steel supplier has engineers and will size the member. If it can be structural lumber, my lumberyard will fax the package of info down to his supplier (Weyerhaeuser) who has engineers on staff to size the LVL beam.
Are these services available to you?
I am a structural engineer, and can size members and connections, but I still avail myself of these services when I need them. I am always interested to see if they come up with the same. Usually, I am a little heavy, but that comes from my being conservative in my calcs.
It is easy enough to size joists and rafters from a table but for beams, you really need to know what you are doing to figure the complexity of loads that can transfer to them. Software to do so costs a couple hundred dollars or so and still needs training.
For basic stuff, I have the yard that sells me LVLs and parralams do the calcs from plans and for unique situations, I hire the expertise of an engineer.
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Our local yard has a guy whose job is to sit at a computer and do take offs from prints. If I need a beam specd out, I take a rough drawing to him and he will figure loads and crunch out a spec sheet, which the town accepts for permit applications. The sheet includes bearing surface requirements as well as beam size. Takes about 3-5 minutes with all the proper numbers available.
Try the APA-Engineered Wood Systems website: http://www.apawood.org/ They have several free downloads: Design of Structural Glued Laminated Timber Columns, Glued Laminated Beam Design Tables, Connections, Substitution of Glulam Beams for Steel or Solid-Sawn Lumber, etc. Also see the American Iron and Steel Institute website. Seach for "Residential Steel Beam and Column Load/Span Tables. Interesting readings.
All of the above still applies, but the table you are looking for is IRC table R502.5(1) Girder spans for exterior bearing walls and IRC table R502.5(2) for interior.
thank you larry and kyle, this forum is an excellent reference!