Size and Construction of Stair Tread Nosings

2016-Normandale-office-parkCommercial stair treads and nosings are a key element in the safety of any stairway construction. Anti-slip stair treads can be found in building interiors and exteriors to help prevent pedestrian slips and falls.

Sizing Stair Tread Nosing Lengths

stair-widthThe length of the stair nosing is dependent on the type of stair construction. Typically, stair nosings are sized with the following criteria:

  • Pan Stair Construction: Width of the stair, minimum 1/8 inch, leaving 1/16 inch on either side.
  • Poured Concrete, Terrazzo or Wood: Width of stair minus 6 inches, leaving 3 inches on either side.

Construction Options

Extruded stair tread nosings are commonly referred to as “stair treads” or “nosings” because they encompass both the stair nosing and a partial tread. They are installed by casting in concrete with the use of an anchor or by fastening through pre-drilled holes. The most common option is a ribbed bar abrasive nosing for cast-in or pan stairs for new construction.

Depending on the age of the building and how much abuse the stairs are subject to, the stair nosings may need to be replaced at some point. To save on replacement costs, it is best to specify and install a two-part system. This system is comprised of two parts: a top extrusion with a ribbed or full-abrasive channel and a bottom with an extruded anchor. The tops can easily be removed and replaced to maintain the initial safety and aesthetics of the building.

As an alternative option, Renovaton treads are an economical alternative to the total replacement of older, worn stairs due to spalling concrete. These treads are installed on top of the stair treads after minor repair to the concrete has been completed. The nosings are constructed with a long nosing in the front and a beveled edge in the back to create a barrier free stair.

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