At this stage I had a house that was pretty much finished. I just wanted to add some flashing to the edges of the roof. I cut six thin strips of tin foil, four long strips for the sloping sides and two short strips for either side of the chimney:
I folded each strip in half along the length:
And snipped one end to a point (you can see the snips at the top of the picture below):
The I glued each strip to the roof and smoothed them down so that they followed the contours of the corrugated card. When the glue was dry I cut the foil at the bottom of the roof hips to make it look like the flashing had ripped as some of the roof panels had fallen away. That gives you this:
The foil is very shiny so I painted it grey then silver to match the roof panels. My paints didn't take to the foil very well but after two coats it stuck well enough.
I've never tried this before and I was quite pleased with it because the foil took the paint differently to the card, so it retains the appearance of being a different material.
So, just a bit of weathering and flocking to go. As it happens, I finished this months ago but I was waiting for better weather and more light to take some decent photographs of the finished item. As UK readers will know, that didn't bloody happen so you'll just have to make do with the pictures I've got. Here's the finished terrain piece, ready for some 15mm action.