Subfloor Delamination

Subfloor delamination happens when the layers of a plywood or oriented-strand-board subfloor absorb water and separate from each other. The wood swells, the glue bond between layers breaks down, and the subfloor can become soft, spongy, or bowed underfoot. A delaminated subfloor usually needs to be replaced rather than dried and reused, since the structural bond between the layers does not recover once it fails.