Shimming main beam? What is the max allowed

Inspected a crawl space that had some weird stuff going on. Looks like 1 main beam was replaced. It was notched and shimmed with quit a bit of shims. What’s the rules with this. Thanks for any help with this

Scrap-wood shims are a no go.

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“The only problem with using wood shims arises when the shims are too small to support the weight/load of the main beams. If the shims are cut from the edges of nominal 2x4s, they are only 1-1/2 inches wide. A single sliver of 1-1/2 inch wide shim will naturally crush under the weight of nearly any beam in a wood floor system. All that the builders need to do is utilize a series (multiple pieces) of wood shims when leveling the main beams in order to reduce the pressure on the shims. Usually, they just use a single piece of 1-1/2 inch wide shim. These shims can be �-inch thick up to 1-1/2 inches thick. Whenever the shim needs to be more than 1-1/2 inches thick, the builder will typically use a piece of dimensional lumber such as a 2x4, 2x6, 2x8 or even 2x10 or 2x12. In these cases, the shims will usually never crush. The crushing problem typically only occurs whenever a single sliver of thin wood is utilized.”

From: The Use of Wood Shims in Residential Construction. Information from JADE Engineering

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& shall be treated material with grain perpendicular to the beam being supported (avoids splitting) & cmu requires masonry cap or top course filled
whenever i’ve done install/repair wood plate shall not exceed 1-1/2" height because masonry cap is available

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Just shoddy work. It would not have taken much more time or $$ to do it correctly.

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The rule is that there’s more wrong there than just the shims.

That’s a Parallam beam or (PSL).

DO NOT cut, notch, or drill holes in Parallam® Plus PSL except as indicated in the Trus Joist® Beams, Headers, and Columns Specifier’s Guide, TJ-9000.
1.888.453.8358 • weyerhaeuser.com/woodproducts/contact

Appears to me that the block work might have been temporary support and not removed, because a PSL of that size would not need intermediate support.
The CMU on the end support appears to be filled, and should have been trimmed down to allow for a P.T. plate for a full bearing of the PSL without notching of the beam.

On a second note, what is the plastic face insulation? Is it a vapor barrier?

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It’s that fully encapsulated stuff that homeowners use so they dont get itchy putting it in. This paralam was a replacement for whatever reason they replaced a double 2x12 main beam with this. Right next to this is a double 2x12 main beam that was either added or is original but it doesnt run the full length of the crawl. It stops on a cmu pier about 10 feet from the next wall. I’ll add some more photos but there was a lot of work done down here and its shoddy.

All kinds of issues there. There are a couple of LVL’s that look like they want to roll over, missing insulation, some falling down, unstable prop to support floor above and galvanized piping and I am sure there is other things that need looked at.
Might be a good time to recommend a qualified licensed contractor to evaluate the whole thing.

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Give them some credit, they used a garbage bag or similar as capillary break :slight_smile:

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That’s basically what I told him. The floors above some of this are unlevel also. For a 1989 build I was not expecting this

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Marcel have you ever seen this before? It was shiny but dry on the blocks and some of the insulation. When I first saw it I thought it was all moisture but it’s not. I’m kind of scratching my head as to what it could be.

Can’t say I have. Was that the only small area with those sparkles? Looks like some sort of glitter.

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Should have used metal to shim it.

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I’ve seen products like Concrobium mold spray leave a glittering film when they dry.

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Looks like the film left behind by slugs.

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That’s what the buyer thought too. It could be but it wasn’t in trails like you would expect. But you might be right

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Yea just one corner of the crawl space. Buyer thought maybe slime residue from slugs. Not really sure I told him I would look into it more for him

Is that an LVL? How many plys ? They notched it so it may not work out anymore. Also how is the plys fastened together?

If this was my inspection I would just state appears to be notched and improperly shimmed. I would suggest a contractor to look at it. I would also suggest checking with local building inspector for proper permits and inspections.