Over the past week, I've constructed three different rooms as "proof of concept" test beds to see if these designs would work. While all of the dungeon tiles incorporated a combination of 1 inch square plastic tiles and tiles made from cork sheets which were painted and textured, my first room (pictured below) was made using a cardboard base with clay walls.

Since this was just a test run, the clay wall was simply rolled and flattened prior to being glued in place. One advantage with clay, which I chose not to use for this particular room, is that I could have etched "stonework" or "bricks" into this medium before it dried and set.
To my way of thinking, the disadvantage to building a room with clay walls is that it can be labor intensive (if you etch the walls) and time consuming.
My 2nd room used PVC sign boards. These were easily cut out and glued in place. I painted them with primer and added some textured paint. I rather like the way this came out. It was also quick and easy to make. NOTE: I recently replaced the chaos knights with the hulking figures seen below left. I bought a set of chaos knights produced by Warhammer for $20 and spent a pleasant evening painting these guys.

My 3rd room used a mixture of PVC sign boards and packing foam. Packing foam is an interesting material. It tends to disintegrate once it's cut and there's a chemical reaction that occurs when using different types of paint. Acrylic paints work the best. Spray paints and particularly clear coatings will literally cause the foam to shrivel and dissolve. Certain types of glue will also cause the styrofoam to break down. Plastic glue in particular causes this product to partially dissolve.
With this being said, I built my wall and then judiciously applied some plastic glue to create the ruined effect seen in the picture below. I then painted it with acrylic paints and applied some flocking using Woodland Scenics turf. I thought the result was spectacular.

Pictured here is a close up of the ruined wall.

If you were to closely examine a piece of cut sytrofoam, you will see that it's made of a hole bunch of little balls. When you apply a solvent like plastic glue to this product, the area around the glue will melt away to reveal these little balls which coincidentally look a lot like rocks.
Since digging out my Hero Quest set since last month, I've been playing with styrfoam to see how I can incorporate it into my growing collection of open tiles.
Take a look at this ruined tower.
When I first started, I had a solid block of styrofoam. The gaping hole in the tower was judiciously made using carefully applied plastic glue.
Here is a closeup of the tower's base.

Here are also some pictures from other sides.


The tower is part of a small collection of specialized dungeon tiles that I've been building for a ruined keep. I am currently working on a wall section as well as a gate house.
From a gaming perspective, a ruined keep could be a lot of fun. An archer up in the tower could play havoc with the players until he was put down. The walls and piles of rubble could all conceal all sorts of traps and nasty foes.
Getting back to the rooms, I think I'm going to go with PVC and styrofoam walls. I may use clay if I need a specialty room and want something hand crafted like a stone fireplace or a well. The materials are all quite affordable and to be candid, I've always been more interested in the painting and building of figures, models, and dioramas than I've ever been with gaming.
Although gaming is fun, I think it's been more fun to work on the ruined keep which is probably just as well since I don't currently belong to a gaming group.























