Chris Walas.... Fantasy Foam.....
All right, a bit of info on the stone house.
Anything thicker than 1/4" is cut from blue foam. Anything 1/4" or thinner is probably from strofoam food trays. The roof is made of two pieces of 3/4" sheet.The main form is cut from 4" foam on the bandsaw, for speed. I drew the basic pattern with a soft pencil and cut the mortar level in with a Hot Wire Foam Factory tool. The texture for the stonework is scraped in with a small Sur-Form. The wood texture is simply drawn in heavily with a soft pencil. Inset areas, doors windows, were cut with sharp knives and the roof beam, tool shed, window sills and mullions were cut from separate scrap pieces of foam.
After lots of conversations with more experienced parties, I've decided to coat the foam with two heavy layers of exterior latex housepaint. I've spoken to sign makers and modelmakers and they all say that unless the model is going to be handled, the latex paint will be fine. I've had a sculpted piece of latex painted foam outside for four or more years now with no sign of wear, except where the wind picked it up and blew it ten feet into a rock!
Outhouse vents (not stovepipes!) are sculpey material. The trashcan is two pieces of foam handcut on the Hotwire Foam factory and sanded to a better, more even finish.
The stone pattern is cut in with a dremel and the texture is done with a sur-form rasp. Pretty quick and easy. A little messy as the foam dust is lighter than saw dust and clings more! The wood texture is done simply by drawing the pattern on the foam with a soft lead pencil. I've used other stuff to draw detail and texture, but a soft lead pencil seems to glide over the surface a little easier.
The Mushrooms are made out of a different foam, a urethane insulation foam as opposed to the blue styrofoam. The urethane is like a more dense version of the common craft store Green Foam or floral foam. It carves much better than styrofoam and can be sanded easily with anothre piece of foam or even your fingers! Those mushrooms are covered with three coats of exterior latex house paint to fill the tiny irregularities.