To make a realistic set of model or miniature faux stone stairs you will need to size them to look realistic in whichever scale you are working. Stairs are sized based on the run, or length of the step, and the rise, or height of the step. To make a set of miniature stairs, you should find foamcore board or sheet foam which is as close to the thickness of your stair rise as possible, in your particular scale. Stairs are normally set to be at a rise of 4 to 8 inches, so you should be able to find something a suitable thickness for your scale. For the set of 1:12 scale stairs shown here, I used 1/2 inch thick foamcore board, but you can also use High Density Insulation Board, Gatorboard, or sheet styrofoam.
To Build a Staircase to Fit a Particular Height - If you want to make a staircase fit a particular existing height, or length you will need to work out how many steps and what height and length they should be before you begin. This is where rise and run come into play.
- Work Out the Stair Rise. - To work out how tall each step will need to be for a fixed distance, measure the straight vertical distance between where you want the top of the highest step and the base of the lowest step. Example - If I have four inches to the landing for my stairs I will need eight steps 1/2 inch thick. This is assuming I will be finishing the landing area with the same stone finish as the top step, so there will be an extra 1/8 inch of height above the total height of the stairs to allow for the top 'riser' which will match the landing.
- Work Out the Stair Run - To work out how long each step will be, you can either work out how much space you have to fit the stairs in, or you can work out how wide you want each step to be (to accomodate plant pots for example). I wanted my stairs to show off pots of flowers, so I made them wide, roughly 1 1/4 inches. To reach a height of 4 inches with the rise above, my stairs would need 7 x 1 1/4 inches or 8 3/4 inches of run space. I reduce the number of steps by 1 to determine the run as the top step in the run is the step off the landing, unless you plan to extend the landing outwards with shaped steps, like the semi circular ones in the photograph on the page before this.