Painting the Museum's Exterior

The walls were taped to a couple of cedar shims and then painted with Model Master aged concrete acrylic paint. I didn't prime the walls with Tamyia fine white surface primer as is my custom, but simply washed them with a mild soap and some warm water prior to painting. I was ok with having the uneven, grey, black-washed plastic as the undercoat as I thought it would give the walls a little more age. 

But, even before any paint was applied, I glued a styrene ledge on the back of each wall, 4mm down from the top, so that the flat roof would have some support. 

So, once the ledges were glued on, and the walls were washed, 2 coats of paint were applied to each piece.