Hi Burco,

I've come across door cards like that, but so far I've been able to find replacements easily enough. Used parts are starting to dry up so it might come to a repair at some point.

I recall seeing a tutorial on replacing the lower section but I haven't been able to find it. Maybe someone else can help with that. I remember it was quite involved.

As for material, I think it's called hardboard. Masonite, Uline, and Ambersand are brands that you can Google and they're all available in 1/8 thickness. Sealing them is recommended if they're exposed to water. I always put a coat or two of clear lacquer or polyurethane on door cards that are off the door.

Take care that your plastic vapor barrier is well sealed and that the tails are tucked into the holes in the door panel. The old duct tape has likely dried out and can be replaced with a better product made for plastic sheet. I use Tuck Tape brand that I get in Canada, but there must be something like it available in the US. It's used for sealing plastic vapor barriers on the interior of homes, over the studs and insulation. If the plastic layer on the door is sealed well enough, very little water should reach the door card.

Besides the outer window seal, water an also enter through the clips holding the molding that runs across the center of the door. I usually brush some seam sealer around any of those that I can reach when the card is off.

Peter