Remedy For Out of Square Stem Walls
Hey All,
Framer on site today identified two stem walls of our slab-on-grade foundation that are about 2 inches out of square. We talked through shifting the walls to be mostly centered on the stem wall, but that seems like a “work around” to a bigger problem.
Is there a solution to out of square foundations?
I have asked the GC to stop until we have both the architectural and engineering elements of the unsquare stem walls sorted out in writing. Is that the wrong tact to take? Any other suggested actions?
Thanks again all.
WD
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Its annoying, but having the wall overhang 1" and sit inside 1" probably will not make much of a difference and will be hidden by finishes when you are all done. I have worked on jobs where angle iron was installed to support the plates on really bad foundations, but I would not go through the trouble for 1". Just snap the plates square. Usually I see foundations that are within 1/4" of square. If your crew is 2" out on a slab I would be a lot more worried about the flatness. If the slab is super wavy, you may have to shim the plates and that can add alot of time and headache for the framers that will need to be reconciled with the GC or concrete sub.
I agree with strausjw; tolerances within 1/4" are normal, while being 2" off might indicate other problems. Assuming that's not the case, I would adjust the plates so they are square, but I would be sure that the concrete is not proud of the sheathing. Old homes and high-performance new homes often have a larger offset between the cladding and the foundation than most newer homes, so having a 2" overhang wouldn't bother me, as long as the studs still have good bearing.
Michael - our design calls for 2 inches of exterior insulation. So, none of the concrete will be proud of the walls. At least per current plans.
Got it. What size are your studs? Were you the one who asked about stud bearing recently? Where you have 2" foam and a 2" overhang, you probably need to use 2x8 studs.
They are currently 2x6 for exterior walls. Yep, that was me. The current design does call for attaching a 2x2 to the bottom of OSB to support the exterior insulation....assuming that is what you are talking about needing the 2x2 for.
From the bottom plates that they have down so far, the flatwork looks really good and flat. I am concerned about getting the titan Holdowns in the middle of the bottom plate with enough edge distance, when installed in the stem wall, to hold the shear on the wall.
Architecturally, the biggest bother is that, 9n the exterior, one wall is on the back patio. An "eye sore", constant reminder and potential problem down the road when we go to sell.
On the phone, the GC is suggesting we make it an 8 inch wall to address the mechanical purchase of the HD on the wall.
I am thinking that I'm going to ask him to draw up his suggestions, get it sent to engineer so we can consider the potential impact on the Architectural elements.
I am also trying to think theough the resell process and if a future inspector informs a potential buyer; how do we put them at easy with the cosmedic as well as the underlying structural details of the wall.
Would engineer sign off be a good idea???
Another option would be to form and pour an extension of the slab, to make the sides square. It would need to be a special type of concrete and you would want to use a bonding agent. That way it's not an aesthetic problem or a resale problem.
Seeing how foundations are often out a bit (although not usually 2"), it's a good idea to have a transition in materials at the top of the stem-walls, and not plan something like having the exterior foam and cladding be continuous.