Laminate Beam Span

Originally Posted By: jremas
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Well?






Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

Originally Posted By: jmyers
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Jeff,


It looks fine to me. Are you sure that is a laminated beam? Looks like standard dimensional lumber to me.

Joe Myers


Originally Posted By: jremas
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It is a 13’ span. The beam is 3-1/2" thick by 14" wide. It is spec’d out for a 40-lb. live load but only supports 1 floor above that is bedroom living space with no roof load. At a 13’ span the LL Deflection is .2239" and the allowable is .4382" so it is running about 51% capacity. Both ends are only required to bear on 1.68" each, but they are on 3" each side.






Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

Originally Posted By: dvalley
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Jeff,


My thoughts were that each bearing end should be bearing on 3 5/8 of wall support. Who requires that both ends bear on 1.68" each? Is there an exception to the rule?

Maybe I can learn something here? ![icon_wink.gif](upload://ssT9V5t45yjlgXqiFRXL04eXtqw.gif)


--
David Valley
MAB Member

Massachusetts Certified Home Inspections
http://www.masscertified.com

"Some cause happiness wherever they go; others, whenever they go."

Originally Posted By: jremas
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Dave, If we go by the IRC, then wood supports only require 1.5" on each side. If the supports were masonry then 3" on each side is the requirement. As far as the 1.68" minimum, that is the spec for the engineered laminate beam that was installed. With this beam being 3" each side, it exceeds the requirements.


Also, if it were on a masonry pocket then a 1/2" of air space would be required on each side including the end.


--


Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

Originally Posted By: dvalley
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Jeff,


You taught me something today. I personally have never seen wood supports at beam bearing ends and never knew that the bearing end could be 1.5" on each end on these supports. I'll keep that in mind. I've always seen masonry pockets with a bearing of 3 5/8.
Now is this bearing for the engineered laminate beam only or all wood beams?
Thanks for the info! ![icon_wink.gif](upload://ssT9V5t45yjlgXqiFRXL04eXtqw.gif)


--
David Valley
MAB Member

Massachusetts Certified Home Inspections
http://www.masscertified.com

"Some cause happiness wherever they go; others, whenever they go."

Originally Posted By: jremas
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All Beams Dave. If you had triple 2x12 as a beam then the 1.5" on wood or 3" on masonry applies. The engineered beams follow the same guidelines unless otherwise specified just like the example I gave you. The specs called for 1.68" so they were just placed at 3" instead of playing around with a 1/4". Unless you had a really anal AHJ then they would have let the normal 1.5" be OK.






Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

Originally Posted By: roconnor
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And, the problem is?



Robert O’Connor, PE


Eagle Engineering ?


Eagle Eye Inspections ?


NACHI Education Committee


I am absolutely amazed sometimes by how much thought goes into doing things wrong

Originally Posted By: ismetaniuk
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This membership was a big waste of my time!



Igor


Top To Bottom Inspections


Glen Spey, NY

Originally Posted By: jremas
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You are correct Igor, this is work that I am doing in my own home. I permit was issued and everything is being done under the watchful eye of the municipalities 3rd party inspection company which just happens to be an engineering company. They have not flagged anything but gave me a hard time in the beginning because the engineer thought that my span would require a 16" beam instead of the 14" that I used. I challenged him on where he got his data and provided him with the data directly from the manufacturer and even threw in a separate calculation showing deflection. I am at 51% capacity for this beam and could have downsized. His problem was that he was using a general laminate beam span table of unknown origin. I challenged that because every manufacturer is different and uses different processes and thicknesses of laminates therefore the spans would be different.


I only wish that I bought a split beam and bolted it together because I had lines on my shoulder from the weight for 3 days afterwords. Way too heavy for one guy.

I just thought I would get a discussion going so I used myself as an example....


--


Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

Originally Posted By: roconnor
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I am not aware of any old LVL beam table that would indicate a problem with that beam. Sounds like the inspector was looking at a lumber table for a typical solid sawn nominal 4x16 DF#2 beam to come up with that depth … icon_rolleyes.gif


Considering they gave you a hard time, you can have some fun and tell the inspector you are really concerned with the beam and the manufacturers data now, and would like a copy/reference on the table he used to double check things. Not that I am advocating pissing off the inspector ... not a good thing ... I am just really curious now how he came up with a 16" deep beam ...

Sounds like the house is a little narrower than 30' (my guess would be 28') from what you describe. Keep in mind you might be around 1/2 the deflection limit, but are most likely around 2/3 the bending capacity at 40LL depending on the manufacturer (also could be lower for 30LL with sleeping areas above if allowed by the AHJ). Always better to oversize beams somewhat, unless you are trying to make an existing install work.

And I like those split beams (i.e. Flitch Beam that usually has 2 pieces of lumber and 1 steel plate in the middle bolted together, but can be other combinations like 2 plates on the outside). Good load capacity that?s better than an LVL (like double 2x10 Oreo Flitch for you) and very durable ... as long as the plate is slightly smaller than the lumber to allow for wood shrinkage. You can split a post or jack stud if the wood shrinks enough to end up with bearing on the plate.

The beam design/capacity issues are beyond an inspection, but I thought you would find that interesting. Plus the shrinkage issue is something to be aware of if you see a flitch beam ... Joe F has probably seen some split porch posts in Queens from that.


--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong

Originally Posted By: roconnor
This post was automatically imported from our archived forum.



P.S. An “Oreo” flitch beam is one with 2 pieces of lumber on the outside and a steel plate in the middle … all sandwiched together with bolts … icon_wink.gif


Hmmmmm ... I'm hungry now.


--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong