SIP OSB panels in contact with raised slab concrete
Our builder decided NOT to use a nailer, and instead placed the SIP panel directly on the 2×4 treated bottom sill plate then nailed the OSB directly into the treated plate. However, the OSB panels, both inside and out sit on the concrete. They did use a closed foam sill seal (blue stuff) so in some cases the OSB is sitting (crushed) on the seal and and many places it is directly on the concrete. Is this a problem? It would seem to us that OSB sitting on concrete or on the thin sealer on concrete would be a problem for the non-treated OSB. They did a good job of nailing the OSB (correct schedule). Is it necessary to create a capillary break? If so what debth and what tool. If we create that break will that create a structural problem with the panels. Thank you.
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Replies
Scott,
We can give you our opinions, but the real one that matters is your SIPs manufacturer who is providing the installation guide and warranty.
I agree and am hoping to understand the problem and potential solutions.
Scott,
Malcolm is correct: the builder needs to follow the instructions provided by the SIP manufacturer.
The detail in the GBA library (below) keeps the OSB skins of the SIPs elevated, so that the OSB does not touch the concrete.
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