My basement floor under the air conditioning unit and water bay is made of 2 inch Styrofoam sandwiched between 1/8th plywood and some form of very thin plastic . These pieces are wedged into the framed square support grid and then covered underneath with a layer of black plastic material. The whole area under the water bay, basement air conditioning etc is beginning to fall off in sections !! The grey/black water outlet is sagging as it sits in one of these sections.
Suggestions please.....thinking of using 2 inch pink solid foam pieces, plastic panel on top side , foaming these panels between the framed squares and then riveting black plastic sheets over the whole underside of this area.
The main basement storage area on the passenger side is also beginning to fail.