Before starting the estimation, we need to know different components of a staircase which I will use in this calculation.

##### Components of the staircase:

1- Step: It is a combination of tread and riser which permits ascent and descent from one floor to another.

2- Tread: The upper horizontal portion of the step-over which foot is placed during ascending or descending a stairway is known as the tread.

3- Riser: The vertical member of the step is known as the riser. It is used to support and connect the successive treads.

4- Waist (String): The thickness of the RCC slab over which steps of RCC rest, is known as the waist.

5- Flight: A series of steps without any platform, break or landing in their direction.

Given Data:

Width of Staircase= 4 Feet

Height of Flight= 10 Feet

Riser= 0.5 Feet

Waist Thickness= 0.5 Feet

Aligned  Length of Staircase = 21.5 Feet

Solution:

No. of Risers= Total Height of Flight/Height of Riser=?

No. of Treads= Total No′s of Riser-1=?

The volume of One Step= Riser * Tread *Width of  Staircase/2=?

Total Volume of Steps= Volume of One Step * Total No′s of Tread=?

Total Vol. of Staircase= Total Vol. of Steps * Vol. of Waist

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