Replacing bottom board

[Bigmike]

After 20 years the underside of my 28x80 mobilehome is in shambles. I have no one to help and I'm sure this is a repair that would cost thousands. So why can't I replace the plastic sheeting with plywood? Laying the insulation on top of the plywood. And securing the plywood to the metal frame with screws or to the floor joists. What would be the results?

[rebar]

I don't see a problem replacing the black rodent barrier with plywood.. Ive wished mine was plywood after a coon got up there and had his way..

The only problem would be notching the plywood around the outriggers, and the middle has sewer pipe's that drop down to drain well that you would have to notch the plywood around. Sounds like tons of work, but if you do, don't paint the plywood as that would trap moisture.. Repairing whats damaged would be my approach..