these basement 'compartments' are built of marine-grade plywood covered by a water-proof white laminate on each side.
the issue is that they may not be supported well enough and since they are not really water-proof because they are not covered on all edges, water intrusion will certainly create issues over time, such as degradation, wood rot, and even other issues, such as mold growth. While the factory tries to seal them as well as they can, generally with sealant along the corners and edges, it's not a perfect answer - water WILL find it's way in.
Thor replaced all our Main and Water bay basement flooring systems back in 2016 when ours started to show mold growth(like mushrooms near the outer edges), the edgings near the outside were pulling away, and while the whole flooring was 'sagging'.
I would suggest that they did not anticipate this, and probably never provided the real adequate support needed under all the plywood base, and not sealing the cut edges BEFORE they 'built' each of these. Anytime you cut the edge of a sealed plywood system, you are now exposing that newly 'unsealed' edge to the elements, no matter how much you try to 'seal' it with caulking. These 'boxes' also had NO element design to allow them to 'drain', either, if/when water was introduced, especially in the wet bay. If you have a water tank, water pump, water filter, water lines, and a spigot water connection in the water bay, you ARE going to have water in the bay, at some point.
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