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Saw this in my new home construction, I am concerned, wondering if this is common. Thanks!

material under ibeam

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bladefist
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2 Answers2

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These are metal shims - very very common.

You install ibeam and either right after install or after joists are installed you want to level everything out. You will need to shim at least one side.

This is really common. Dealing with ground settling, concrete shrinking and so on over a 60' or longer stretch you have two options:

  1. Pay a ton of money to make sure all the planets align and your beam is perfectly level on concrete cut-outs. (and after all that money, it could still be off)

  2. Put $2 worth of metal plates under to shim.

Those plates are not going anywhere - the weight of your house is on them. As an inspector it would not concern me in the least.

The only fear you should have is an overzealous inspector in your town - but this should be the same guy that signed off on the house in the first place. They could require the plates welded to the ibeam or to get a welded piece on that. This would require a temp post, jack it up and weld it on.

Also not sure what it looks like if you go further but I like my ibeam resting on a steel flange. I don't see that here and that bothers me more than anything. And looking at the picture further I would like to see the top of the beam - really doesn't make sense on what is going on there.

Notes based on 2nd picture:

  • Some cities may have a max height of the shims. I have seen 4" more than once. I don't believe there are any code standards on this.
  • The height may not meet code but the most concerning thing is that the plates are not stacked appropriately. The fact is there may be a lateral force due to this. Probably negated by the extreme downward force.
  • And of course they are not welded or tied to the ibeam
  • How concerned would I be as a home owner maybe a 3 out of 10. I mean it wasn't done perfect but it isn't going anywhere. Just the fact that they used this many shims shows they took time to make sure your floors were flat and level.
  • The verdict... I don't think it will pass inspection. I think inspector makes them weld a solid piece to ibeam or steel piece plus 1-3 shims. I would give this maybe a 10-20% chance of making it. The good news it is a relatively fast fix and will only cost builder a few hundred.
DMoore
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Shims are OK but Verify the Beam

The metal bearing shims are somewhat normal for this application (residential construction) and is used to bring the top of the beam to the proper elevation though this is more than typical adjustment. It's possible that the beam was originally designed to be deeper and was changed as some point and the dimensions on the plans were not updated, or the contractor made a mistake. I would expect it to be within a 1/2" or so.

The shims do not need to support the full area of the beam between the steel and the concrete as the area just needs to be enough to keep the load down below around 2500 psi which is a lot, a 4 in x 4 in contact area could support 40,000 lbs. I have heard that sometimes the inspector wants the blocks tack welded into place for a mechanical connection so the shims can't move but I have not seen that to be the case personally

This situation is a red flag about the beam size since the next larger size of beam would be 2" deeper and appears that it would also fit. I would measure the depth of the beam and compare it to the beam called out on the structural plans. The beam will have a name such as WF10x12 where the first number is the depth in inches

Note that I deleted my original answer because I had misinterpreted the question and picture

Ack
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