We wanted give the walls of Hagrid’s hut the “made out of stone” look and rather than just paint lines on flat cardboard, we went 3D.
For the two side walls, we adhered large sheets of Styrofoam to the cardboard base using Glidden Gripper (a primer-like substance which is good for adhering foam to things).
Then, using a soldering gun, I carved the rock outlines into the Styrofoam.
After that, I painted a dark gray color in the cracks…
…and then painted a lighter gray color on the flat surfaces of the rocks.
For Hagrid’s doorway, I created the stone archway out of foam and carved it the same way as the walls.
I then painted it in a similar way to the walls, and painted the door brown.