Plastic under TT

[mudbud255]

Previous owner must've had a blow out and damaged the plastic wrap under the TT. Wood floor is still good just where the damage is the duct taped is coming apart. (Previous owner used duct tape to reseal insulation wrap) I saw this when we purchased TT, and could feel the underside was still intact.Is their a better fix for this or do I just need to keep duct tape on hand? The plastic wrap is damaged from the frame to the outside and in between two steel runners. It's about a 12x18 inch section above tires. Any help would be appreciated, want permanently close this up to prevent damage. Thanks guys

[Oasisbob]

What are the aprox, dimensions of the damage? I would consider screwing a thin sheet of plastic well over damage and using under carriage paint to seal.