Stair Tread Nosing

Stairs, stairways, staircases, steps - whichever title you use, they are a common component of residential, commercial, and industrial structures, and one that the vast majority of people take for granted. However, there is much involved in the design and construction of staircases.


When building stairs, it's usually best to make each step out of two deck boards. The tread is the part of the stair you walk on. It is held in place by fasteners that are attached to the stair stringers' horizontal surface. When putting in the tread, many builders extend the front end of the deck boards over the stringer by the thickness of the riser plus about an inch as a nose. This angled step keeps the riser from getting too loose over time. It is a nice touch that makes the stairs stand out. Most of the time, a bull nose or radius edge looks best at the top of a set of stairs. Most 5/4 wood decking comes with a round edge. You can use a router to round over the edge of a 2x6 with a square corner.


Read more: Stairs Safety Glazing Requirement


Stairway Terminology

When discussing a stairway or staircase, it is essential to distinguish and comprehend the numerous components that comprise the whole. The following phrases are routinely used by designers and manufacturers of staircases to describe and indicate each major stairway component or measurement:

Stringers – These are the sawtooth-shaped pieces on either side of the stairway. They are the main load-bearing supports.

Risers – The riser is the amount of vertical space between each step on a staircase. When the staircase is closed off, a board will appear at the back of each step and run vertically from one step to the next higher or lower one. Some staircase designs require an open riser, so riser boards are not used.

Treads – These are the flat surfaces that people will step on. Runs are another word for treads, but most people just call them "steps" when they mean individual treads.

Nosing or Noses – This word is used to describe the part of the tread that hangs over the rise right below it. The nose of the tread is a very important part of the tread because it is where most people will put their feet first when going up or down the stairs.

Landing – The landing is the space at the top or bottom of a set of stairs or the platform between two sets of stairs.

Width – The width of the stairs is the distance between the stringers, which is the length of the risers and treads from left to right. By law, there are minimum width requirements for stairs that must be met.

Headroom – Measures the height between the steps of a staircase and the ceiling above. The measurement is based on an imaginary line that connects the edges of each step and runs parallel to the sloped ceiling above the staircase.

Types of Stair Treads and Noses

Choosing the right stair treads and noses (or nosing) is an important part of keeping people safe and reducing slips, falls, and injuries. Step treads and noses can be made of different materials, come in different styles, and have different finishes, depending on what the stairs need to do. Here are some of the things to think about when choosing treads and noses for stairs:

Location environment – Is the staircase housed indoors in a climate-controlled space, or is it exposed to the weather outside? Changes in temperature and the presence of precipitation are crucial considerations when choosing between tread and nose designs.

New design or repair/retrofit – Is the staircase a new design or an old one that is being updated or retrofitted to improve safety? Other treads and nosings can be readily added to an existing structure as part of a retrofit or as an overlay over the current treads and nosings. In the case of overlay work, it is essential to select a nosing overlay design that is compatible with the existing top surface material, whether it be ceramic tile, porcelain tile, carpeting, or wood. This will ensure a seamless transition between different material surfaces, hence preventing the creation of a tripping hazard.

Anticipated loading – What are the predicted traffic levels, load levels, and load types (pedestrian, industrial) for the staircase? This will assist in determining material options, intrinsic strength, and load capacity.

Material options – Wood is a frequent material choice for treads and nosing in residential settings, while commercial and industrial buildings may use different materials such as cast aluminum, carbon steel, cast iron, bronze, brass, or PVC. There are also laminate stair treads and nosing made from engineered wood such as MDF or HDF. There are various top cover materials that can be added to existing treads, including as carpeting, rubber-based mats, and fiberglass composites using compression molding.

Covered vs. uncovered treads and nosing – Another factor to consider is whether or not the tread and nosing materials are intended to be covered with another product or left uncovered. For instance, if the treads of a staircase are to be carpeted, this will affect the selection for the underlying tread material and can also affect the design of the nosing that will be employed.

Tread level – While the treads of the majority of stairs are level and meet the risers at a straight angle, there are instances in which the treads slant slightly or are curved. These parameters will be especially important when selecting a product to overlay an existing structure.

Aesthetics – In many situations, the visibility of treads and nosing necessitates that the appearance of the staircase itself is also a significant factor. Restaurants, hotels, theatres, and other commercial settings may demand a tread and nosing design that combines the necessity for slip resistance and safety with the goal for aesthetic appeal and a consistent appearance across the room.

Other considerations – For increased visibility, high-contrast or colored visual markers can be applied to treads and nosing to make it easier for walkers to recognize the edges of each tread. As part of the treads and nosings, there are also photoluminescent strips designed for usage in low-light circumstances.

Be sure to check our deck design tool for any further planning as such things should be preplanned for. You may also further check your building code for more details as this article is written in the light of the federal code and your local building code and its instructions may vary.

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