Rusted tin roof

My initial idea for the roof was corrugated cardboard painted to simulate tin since I've seen that done before with good results, but I found two items that allowed me to go for an even more durable finish. The first was a pack of 12 metal sheets with an adhesive backing. Each sheet measured 4in x 12in and the pack was very reasonable in price - $5 at Hobby Lobby. I then bought a paper crimper by Fiskars to turn 4in x 6in pieces of the metal sheet into corrugated tin roofing.

After transferring the pieces onto a foil covered board, I sprayed them with a thin coat of Testors flat black spray paint. Once dry, I layered on acrylic paints to simulate rust. The metal had an adhesive backing, but I added some tacky glue after peeling away the backing to affix the pieces to the roof. Some of the edges lifted as the glue dried, but that only added to the worn effect.