Covering up foundation with wood siding
I want to visually align my trim with the door sill by extending my siding down about 6 inches to cover part of the foundation.
Our current setup:
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The foundation extends ~12 inches above the finished floor level, with wood framing above that.
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The foundation wall is block, covered with exterior foam and a rough stucco finish.
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Above the foundation, we plan to install strapping (rainscreen) and attach Maibec wood siding.
My main question: Can I safely attach strapping through the stucco → exterior foam → block foundation using Tapcons and then mount siding onto it?
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If so, are there best practices to ensure a secure installation while avoiding moisture issues?
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I’m considering a water table board (possibly PVC) at this transition before installing the wood siding above.
I’ve attached photos to make it more clear what I am attempting. First photo is the exterior, and the second photo is the interior to give an idea as to how high the foundation raises above the floor.
Appreciate any guidance!
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Replies
I avoid PCV products when possible but this is a good place for it, due to the proximity to grade.
I don't have experience fastening through stucco and foam but I would expect the stucco to be prone to cracking, so be very careful. I would predrill a countersink for the screw head.
Be sure to use a high-quality tape (something better than that red stuff) to extend your WRB drainage plane down over the face of the stucco. Siga Fentrim is a good choice because it sticks well to clean masonry.
I second the PVC trim idea.
Along with the proximity to the ground, you then don't have to worry about air gapping behind it. You could place PVC directly on top of the stucco, not worry about rot, and hopefully will end up flush or close to flush with the door trim.
Get a sample of your planned maibec siding compared to what's available for pvc trim. Smooth faced PVC might be the best match to the maibec, but there is also "wood" patterned. You can colourmatch paint the PVC to the same colour as the maibec. You'll probably still see the difference in texture but it might be close enough to still look good.
Jamie