The beam is too deep Mr. Engineer

[ANE91]

12-foot span supporting two residential stories, (2)14” LVLs flush, joist bays are 12’ and 16’, contractor wants 9-1/4” instead. Deflection controlled. No chance of reconfiguring the floor plan to cut down the trib width or add interior supports. I can’t think of a way to make this work…5 or 6 LVLs feels like crazytown. Any creative ideas before I crush his dreams of a mildly taller ceiling?

I’m sure there’s plenty of other posts about this exact topic, but I wanted some contemporary feedback while I searched. Thanks y’all.

 

[SE2607]

Could the reason be related to providing rotational restraint at wood bearings? I know this can be done with a flange plate bolted to the wood, but that can be messy.

Rotational restraint? I'm assuming the original analysis considered the supports as pinned and free to rotate. I, too, like to have steel posts supporting steel beams, but, when I do, I weld the beam to the column (because, usually, there is no room for a cap plate) analyze the beam/columns as a frame. This not only reduces the beam size but also more correctly analyzes the column because, with rotation, there is moment.

 

[jerseyshore]

Rotational restraint? I'm assuming the original analysis considered the supports as pinned and free to rotate. I, too, like to have steel posts supporting steel beams, but, when I do, I weld the beam to the column (because, usually, there is no room for a cap plate) analyze the beam/columns as a frame. This not only reduces the beam size but also more correctly analyzes the column because, with rotation, there is moment.

9 out of 10 times I use a knife plate since there is no room for a cap plate. No welding required. Simple bolting.

 

[Ron247]

not good at shorter spans as the end reactions are typically very high.

XR250, Could you explain the correlation between short spans and very high end reactions. That has not been what I have seen over the years.

I am generally using flitch beams on remodel projects more than new-build. Contractors I work with prefer the flitchs over the steel beams.