Dog legged staircase is the most economical staircase, these stairs are arranged with two adjacent flights running parallel with the mid-landing.
They are usually provided where there is less space, causing in economical use of available space.
In such a staircase, the stair landing is provided to a level at which the direction of flight changes.
Introduction to Dog legged staircase:
Dog legged staircase is the simplest type of staircase by which a flight of stairs moves one half step before 180 degrees and persevering with upwards.
Due to its appearance in sectional elevation, it is called Dog Legged Staircase, it is a very common and popular type of stair consisting of two flights that run in opposite directions separated by a landing in the middle space.
Dog-leg ladders are used when the available space is equal to twice the width of the stairs and this stairs lies in its compact layout and has better circulation from a design point of view.
Details of dog legged staircase:
To several floors of the building, the stairs provide access and there are a series of staircases with landings at reasonable intervals.
Each steps has a tread and a riser and the stairs are made up of individual steps.
The riser is the vertical section between each step of the stair and the floor is the flat part on which you step on.
Landing is provided according to the level at which the direction of flight changes and it is the most economical ladder.
Requirement for good stairs:
For an easy, fast and safe ascent or descent of dog legged staircase any efficient stairs must has the following criteria as follows:
It should be located to obtain adequate lighting and ventilation with easy access from all rooms.
Length of Flight:
A flight must have no more than 16 risers and no less than three risers.
Pitch of Stairs:
From 15 ° to 55 °, the stairs are bent and the recommended angle is between 25 ° and 40 °. The long stride should be leveled using the landing.
The width of the landing should be less than the width of the flight of stairs.
The rise of each stage on flights and landings between floors should be uniform and any variety can ruin the peace and ensure comfortable access, the climb is provided.
Example of dog legged staircase design:
Designing a dog legged staircase for a residential building where the floor-to-floor height is 3.3 meters and the area offered is 2.5 meters x 4.5 meters.
Mainly, for residential buildings, we undertake riser and the tread of every step is 150 mm and 225 mm.
Dimensions of Stair hall:
I = 2.5 m x 4.5 m
Height of Floor = 3.3 m
Total No. of flights = 2
Height of one flight = 3.3/2 = 1.65 m.
Rise = 150mm &
Tread = 225 mm
So, No. of risers = 1650/150 =11.
Number of treads = 11-1 = 10.
Stair adopting width = 1.2 m
The length required for 10 treads = 10 x 0.0225 = 2.25 m.
Width of landing = (4.5-2.25)/2 = 1.125 m.
Advantages of dog legged staircase:
The dog legged stairs has the following advantages as follows:
1. Efficient use of space: This type of staircase allows for a more compact stair arrangement and covers much less area than a straight ladder.
2. Privacy: If you want to separate one floor from another for any reason, these stairs are great for users, these stairs provide enough privacy as the top floor cannot be seen and vice versa.
Disadvantages of dog legged staircase:
This staircase has the following disadvantages as follows:
1. This type of stairs is not easy to construct.
2. The handrails on these stairs require careful planning.
This staircase is called dog legged staircase because the slope of the steps is much like the dog foot.