Stair Riser Design
The Design of the Stairs
The design of many of Pittsburgh’s city stairs is the same: a three inch thick plank of concrete with a three to five inch gap between each stair tread. Where these stairs are built close to the ground, this inexpensive and easy to maintain design provides a comfortable staircase to climb. However, since many Pittsburgh staircases are built far above the ground, these open gaps can make climbing many of Pittsburgh’s stairs unnerving. The proposed stair risers are designed to block this sometimes unsettling view through the city stairs as well as to create a canvas for artistic expression on what would otherwise be just another utilitarian part of Pittsburgh’s urban landscape.
Stair Riser Design
These concrete stair risers are designed to be inserted behind each stair tread, and to lock into place using two steel reinforced tabs. The displayed area of each stair riser will be between three and five inches high and about four feet wide, not including the narrow support tabs. The full dimension of each stair riser is between six and eight inches tall and about four-and-a-half feet wide. The weight of each riser will be about forty pounds in most cases. These stair risers will not cover the tread area of the stairs or interfere with drainage of the stairs in any way. As discussed, each stair riser will have a recessed area for mosaic tile or other raised artwork. Alternately, this canvas area of these stair risers can also be used for designs or words cut into their surface.
Stair Riser Material
The material of these stair risers will be steel reinforced concrete with the use of an aggregate that will make them stronger and lighter than common concrete. There will also be a steel reinforcing bar (rebar) cast into each stair riser and extending out into the support tabs for additional strength. These stair risers will be precast and fully cured before they installed with mortar or durable concrete adhesive.
