Fastening Wall Plate to Slab on Grade
Are there special requirements when remodeling walls in a house that is slab on grade? This is a Home in Cincinnati so it falls under the RCO (Residential Code of Ohio) which is based off of the IRC (International Residential Code). I have located the code 403.1.6 Foundation anchorage, in the 2019 RCO (I believe that is the latest) that says you must use min. 1/2″ diameter bolts not greater than 6′ O.C. and no less than 12″ from the ends of the plates, and that the bolts have to extend not less than 7″ into the concrete. This seems strange for remodeling since I have seen many examples of people using other kinds of fasteners that are not 1/2″ diameter and not 7″ into the concrete. It is also strange since most slabs are only around 4 to 5 inches thick except for at the perimeters. Is there other codes somewhere that make exceptions for remodeling and interior walls especially non-bearing walls that are on concrete slabs? How about all of the basements being remodeled into finished basements–what are they using to fasten the bottom plates to the concrete floor?
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Replies
Hal,
It looks like you've got a good handle on the requirements. Those requirements are generally for exterior walls, and the interior partitions, assuming they're not designated shear walls, can be fastened using much less of a fastener. Many people use Ramset nails, the kind that uses the powder actuated gun to drive them into the ground. Others use tapcons or similar masonry screw. Some people use wedge anchors, like the redhead pins or bolt style.
Try not to drive them all the way through the slab, in whichever case, so that you do not puncture the vapor barrier, assuming one exists.
I would interpret this as the anchor bolts are required for load bearing walls, both interior and exterior, non bearing partitions do not typically need this type of anchorage. If in question, ask your local inspector...