beam splice

csauveur · 08-11-2012, 02:24 PM

I am carrying a span of 26 ft with with 4-ply 2x10's. I need to put two splices in the beam based on my materials and I am wondering if there is any general minimum requirements on how far apart the splices have to be?

tony.g · 08-11-2012, 04:05 PM

Quote:

Originally Posted by csauveur

I am carrying a span of 26 ft with with 4-ply 2x10's.

Wondering if splices might be the least of the problems; is this beam actually spanning 26ft clear, or is it propped anywhere?.. and what's it supporting?

sixeightten · 08-11-2012, 04:10 PM

4 2x10's spanning 26' wont even carry themselves. I hope there are other posts.

Daniel Holzman · 08-11-2012, 04:40 PM

Sixeighteen, I do not know on what basis you believe that 4 2x10 cannot even carry their own weight. Assuming a maximum allowable bending stress of 1200 psi, and a modulus of elasticity of 1.2 million psi, and assuming adequate fastening of the members to each other (easily accomplished using proper nailing pattern), such a beam is capable of carrying more than 90 lbs/ft at a factor of safety of 1.0. The actual allowable load will vary depending on code requirements, the actual strength of the beam, and the actual modulus of elasticity of the wood. The allowable load may be limited by deflection criteria, however a beam made of 4 2x10's is perfectly capable of carrying substantial load beyond its own weight at a span of 26 feet.

The question of splicing is interesting. Typically splicing of individual beam elements is accomplished by selection of the appropriate nailing pattern, however the individual beam elements can also be bolted, or can be screwed together if structurally rated screws are used. Whether the beam as constructed is capable of handling the imposed load is generally determined by an engineer, architect or beam fabricator, and of course must be approved in advance by the building inspector from whom you are going to get a permit. You are getting a permit right? The nailing pattern required to attain sufficient strength of splice is also normally specified by the engineer who designs the beam, since beam design is NOT typically specified in the building code.

Joe Carola · 08-11-2012, 04:43 PM

Quote:

Originally Posted by csauveur

I am carrying a span of 26 ft with with 4-ply 2x10's. I need to put two splices in the beam based on my materials and I am wondering if there is any general minimum requirements on how far apart the splices have to be?

Who designed this? It should be on the plans. How many columns? What is the for? Do you have permits?

tony.g · 08-11-2012, 05:24 PM

Daniel;as usual your figures are correct and reasoning impeccable. However, in practice I would suspect that the beam is to carry a lot more than 90lbs/ft
(presumably at that figure it would only be supporting a 2-foot width of floor along its length - which can't be the OPs intention)

Personally I think deflection is going to be the killer here. Even at only 90lbs/ft, the deflection will be getting on for 2". If it is to support a full floor, it'll be like a banana.

Daniel Holzman · 08-11-2012, 06:07 PM

Tony, you are totally correct, and as you noted nowhere did I suggest that the beam was adequately sized. That is why engineers were born. However, the OPS did not ask about adequacy of sizing, so I only addressed the splice issue. I only noted the capacity of the beam because of the comment by sixeighteen, not to suggest in any way that the OPS could safely use the beam for whatever purpose he has in mind.

tony.g · 08-11-2012, 06:26 PM

Quote:

Originally Posted by Daniel Holzman

Tony, you are totally correct, and as you noted nowhere did I suggest that the beam was adequately sized. That is why engineers were born. However, the OPS did not ask about adequacy of sizing, so I only addressed the splice issue. I only noted the capacity of the beam because of the comment by sixeighteen, not to suggest in any way that the OPS could safely use the beam for whatever purpose he has in mind.

Yes, I know full well you were commenting on 6/18s post and not on the adequacy of the beam for any particular purpose. I personally was just curious to see what the potential deflection could actually be - SCARY.

I just hope the OP takes this on board and supports the beam somewhere!

**kwikfishron** · 08-11-2012, 07:16 PM

Quote:

Originally Posted by tony.g

I just hope the OP takes this on board and supports the beam somewhere!

Me too but I have to assume OP wants to span 26’ with a single scabbed together beam.

What would be the point of splicing anything if there were intermediate supports?

If there were you could simply have two 13’ beams or three 8’8” beams for an example.

sixeightten · 08-11-2012, 09:25 PM

My post was meant to draw attention to how ridiculous the scenario was. 4 2x10's nailed together will surely hold themselves up. Gonna deflect an awful amount that would not be acceptable on any job that I have seen.

Joe Carola · 08-11-2012, 10:07 PM

Guys,

It doesn't take a genius to figure out that he can't span 26' with spliced 2x10's and no columns. Let the OP come back and explain. Why waste time guessing.

mae-ling · 08-11-2012, 11:40 PM

How about 4-2x10 spanning 24', yes there are splices.
Seen it done successfully on a 16' wide garage that a guy added a 14' lean to on to it and removed the wall.
Used cables from the top on the ends under a solid metal shaft in the center of the beam and back to the top, on each side of the beam, with turn buckles to tighten it.