Directions for Building Terraced Stone Steps

Stair Placement

• Before you begin building the stairs, determine the layout of the stairs. Identify the top and bottom of the stairs. At the top of the slope, place a stake with a string attached. Hold that string level from the top point and pull it over to the location of your bottom step. Measure from the string down to the ground and the length of the string to get the overall rise and run of the stone staircase. Generally, you want the treads of the stairs to be between 4 and 7 inches above the previous stair tread. The size of the stone used for the tread helps determine the height of the riser. The larger the tread, the shorter your rise should be. For example, a 19-inch tread is comfortable with a 4-inch tread height, while a 13-inch tread is better with a 7-inch tread height. Use your calculations and the size of the stones you choose to determine how many stairs you need to cover the slope and where they will be situated.

Step Components

• Each step uses a large, flat stone such as flagstone to create the treads. You also need smaller stones to create the risers for each step. The risers go in first to mark the front edge of the riser. These stones also hold gravel in place to promote drainage and to support the steps. Once the risers and gravel are in place and level, the flat flagstone pieces go on top with a 2-inch overhang beyond the front edge of the stair's riser. The ground is prepared one step at a time with each step installed before the next one is set in place.

Step Installation

• Start with the first step at the base of the slope. Dig a trench to accommodate the stones that create the risers. You want part of the stone below the dirt line to help hold it in place. The amount of the riser stone sticking above the ground should be high enough to get the calculated height when added to the height of the tread. For example, if the tread is 2 inches thick and you want a 5-inch rise, leave 3 inches of the riser stones exposed. Dig down an extra 2 to 3 inches and fill the bottom with gravel for drainage. Position the tread riser in place and backfill it with additional gravel. Check the surface to ensure it is level.

Finishing

• Once you prepare the base for the step, position the flat flagstone tread on top. Check to ensure the stone is level and overhangs the riser by about 2 inches. You may need to use smaller pieces of flagstone at the back of the stairs to get a large enough tread to fit your design. Take out more soil underneath or add more gravel as needed to get the flagstones level. Continue up the slope, digging out each step and positioning the stones. When the stairs are constructed, dig along the stairs to create a sloped transition from the surrounding ground and the steps. You can also add plants along the stairs to help them blend in.