Originally Posted by overlander63
Andy, the pans I have seen are galvanized steel. can aluminum be used instead, or would galvanized be the preferred replacement?
An aluminum "holding tank pan" would not be a good choice because it is far more subject to corrosion from road salts, etc., kicked up by the tires. But, it can be used even though it would have a limited life.
Granted, Airstream uses it underneath the plywood that holds the large water tank in place by the axles. But that area does not get the brunt of water that is kicked up by the tires when towing in the rain.
Galvanized holding tank pans are the "cheapest" yet effective, followed by "stainless steel."
This is not a place to use wood, in any form.
First of all solid wood is not available in widths of 24 inches or so, therefore plywood must be used.
Plywood being made with "plys" will delaminate in short order when it gets wet.
Even Marine plywood, wouldn't last very long either.
Modifying the way Airstream designed the coaches to be something "less than" is not wise, especially for a holding tank pan.
Modifying them to be "equal to" or "better," is the "do it once and be done with it way."