Sill plate anchor
arnoldk
| Posted in General Questions on
Hi,
I am looking for some feedback as to which sill plate anchor is best to use for a slab on grade for the exterior load baring wall?
I know the standard is the J-bold but from some experience they can be a pain to line up your wall when standing them up and often there is at least one bolt that lines up with your studs.
The other options, epoxy adhesives, screw anchors and wedge anchors I am not very familiar with but they would allow you to place them exactly where you need them after the walls have been all lifted.
Thank you,
Arnold
Arnold
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Replies
Wedge anchors are risky on new pours--they can easily blow out the concrete. (Ask me how I know...) I often spec Simpson Titen HD screw anchors. Easy to install, no epoxy required.
Hi Michael,
I am assuming they are just as strong as the standard J-bolt?
Thank you,
Arnold
Arnold, it depends on embedment depth, concrete strength and condition, etc.. In general I doubt a screw anchor would have quite as much holding power as a J-bolt, but enough for most applications. More info here: https://codes.iccsafe.org/content/IRC2018/chapter-4-foundations#IRC2018_Pt03_Ch04_SecR403.1.6.
Simpson Titen HD screws can require special inspection to install. They have load charts.
I spec them for interior non shear walls only. If shear wall bolts are misplaced I spec epoxy. I am concerned about the long term 30-40 year possibility of corrosion on the Titen HD in a critical installation.
The j-bolts are are a lot cheaper and proven- have the framer onsite when the concrete is poured just to make sure the embed bolts are correct.
Thanks Tim and the framer is going to be me. Our framer hasn't given us the runaround when we asked to for a formal quote with a start date as we had discussed earlier this year so we can secure that spot in their schedule.
Thanks,
Arnold
Here's a good article from famous dancer and comedian Tim Uhler/@awesomeframers: https://www.jlconline.com/how-to/framing/anchoring-mudsill_o
There's another aspect to this to think about , which is the concrete finishing phase. It's easier to finish concrete (IMO) to a flatter surface where the sill plate ought to go, than to finish around cast-in-place anchor bolts. It's easier to put walls in place (IMO) without anchors in the way, and align them to where you want them to be.
I don't buy the argument for Titan HD's rusting after a while. They're ginormous, and if they rust, all of the 3 1/4" nails holding every stud to the sill plate will already be toast, and every 2 3/8" nail holding the sheathing on will be even more toast. Also remember that they're primarily for shear, and not uplift. They wont save your house in a tornado, but they'll keep it from sliding around even in the event that they come a little loose.
They do have drawbacks - the concrete ought to be cured, shouldn't hit rebar and all that. But to me, they're a more efficient solution that is effectively as strong, up until they're not, and in that case, it wouldn't matter anyways.