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Stair Calculator ? An online tool for measuring different parameters of a stair

The Stair Calculator belongs to an online tool for measuring different parameters required in building up the stairs. Just put the values in the fields provided in the calculator and click on the calculate tab. A fraction to decimal conversion table for common fractions applied in measurements is also given at the bottom of the page.

Given below, some useful terms in stairs and common building codes :-

Stairs are available in several forms. While constructing a basic staircase, proper consideration should be given on different numbers of parameters, calculations and building codes which vary from the length, width, and height of certain segments of the stairs. Building codes change at a local level, and a person constructing a staircase should abide by the codes specific to their locations.

Run/Tread: The run or tread is the segment of the stairway that a person walks on.

Its length is calculated from the exterior edge of the step that contains the nosing if it exists, to the vertical section of the stair known as the riser. While calculating total run of a staircase, the length of the tread over the last riser is excluded in the calculation. Also, when nosing exists, total run is not just the sum of tread length, as the overhang resulting from the nosing should be deducted from the total run.

According to building codes, the minimum length of a tread should be 10 inches (25.4 cm).

Rise/Riser: The rise, or height of a step is calculated from the top of one tread to the top of the next tread. It does not refer to the physical height of the riser since it does not include the thickness of the tread. With the number of risers, devoid of the number of treads, the number of steps in a staircase is determined.

According to building codes, the maximum height of a riser should be 7.75 inches (19.7 cm).

Nosing: The nosing belongs to the protrusion at the edge of a tread overhangs the riser underneath. Not all steps contain a nosing, but if exists, the nosing is contained in the length of the tread. The prime objective of a nosing is to enhance the safety with the arrangement of additional space where a person will be able to keep its feet.

As per common building codes, the nosing should contain a minimum length of 0.75 inches (1.9 cm) and a maximum length of 1.25 inches (3.2 cm).

Headroom: Headroom stands for the height calculated from the top of a tread to the ceiling over it. The building codes for headroom are mainly provided to retain adequate room for people to use the stairs at ease and the codes normally need far more room as compared to the average height of a person to facilitate shifting bigger objects like furniture.

According to building codes, minimum 6 ft. 8 inches (203.2 cm) should be provided for stair headroom.

Stair Width: Stair width is calculated from edge to edge of each side of the tread, perpendicular to tread length. When measurements of length remain traditionally longer as compared to those of width for rectangles, in the case of steps, the width is normally the longer side. Stair width excludes handrails.

According to building codes, the width of stairs should be minimum 36 inches (91.44 cm).

Handrails & Guards/Guardrails: A handrail belongs to a railing that runs up a stair likely for users to hold while ascending or descending a staircase. A guard belongs to "a building component or a system of building components which are situated adjacent to the open sides of elevated walking surfaces that reduces the scope for falling from the walking surface to the lower level." Guards can comprise of rails (guardrails), but can be any number of other constructions like walls, half-walls, or even a bench.

Building codes normally need guards for stairs which contain a total rise in excess of 30 inches over the floor, and these guards should be minimum 34 inches (86.36 cm) in height calculated from the top of the treads. Likewise, handrails should remain 34 and 38 (96.52) inches high calculated from the top of the treads, providing a diameter among 1.25 inches (3.18 cm) and 2.675 inches (6.79 cm).

Stringer: A stair stringer stands for a structural member that provides support to the treads and risers of a staircase. Normally, there are three stringers in a staircase: one on each side, and one in the middle. Stringers can be seen always, but are visible on stairs with open sides. The stringers can either be cut to the shape of each step, or sometimes are uncut and conceal the edges of the treads.

To perform online calculation, click on the following link

Stair Calculator ? An online tool for measuring different parameters of a stair