Shimming Between mudsill and plate
AGoldstein
| Posted in General Questions on
Do you think it’s worth shimming level if foundation isn’t perfect? If J bolts are too short to go through both mudsill and bottom plate, how would you recommend resolving this?
Not sure why but I can’t reply to any posts, so I just edited this to reply:
@Freyer_design That’s a good idea. I emailed to ask if they’d be okay with pictures. I could always mark the locations of nuts and expose them by drilling plate above later if needed.
@Randy Williams do you shim under mudsill or add another plate on top of mudsill and shim in between? I’ve been told shimming under mudsill can prevent the sill gasket from air / water sealing.
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Replies
Why don’t you just do a hole saw where your bolts are on your upper plate so you can see your nut and bolt. I dont know about leveling with shims but seeing your bolt with double bottom plate doesn’t seem too difficult. If you need to take picture of washers if you think inspector will be pain about it
If your concrete foundation isn't flat or level, you should shim or grind, or you will fight the humps and dips all the way to the roof. We've accomplished this by shimming the mudsill or shimming or trimming the floor framing to make the assembly flat. For humps in the foundation, get a cup grinder to remove the concrete.
Shimming is worth doing if the foundation is not perfect, because it helps distribute the load evenly on the base plate and the support Geometry Vibes. Reduces the risk of warping or cracking the base plate over time. Ensures the correct verticality of the upper structure.