What is the Process of Stair and Step Construction
The construction of stairs and steps consists of many steps, such as designing, preparing foundation, building framework, placement of reinforcement steel bars, concreting, and finishing and curing. The following are the steps for the construction of stairs and steps:
The designing process of stairs and steps requires thorough knowledge about design aspects and site study. Some of the main factors that influence the design of stairs are floor height, width of stairs, risers depth, thread width, thickness of the stairs, angle of the stairs, load applied on the stairs, and other aspects which requires an expert to design the perfect stairs.
2) Foundation and Support for Stairs and Steps
The foundation on which stairs and steps lay needs to be constructed properly so loads of the stairs are transferred in to the ground successfully. Proper construction is also important to resist the movement of stairs. For example, if the plinth beam can be seen at the beginning of the stairs, then reinforcement steel bars can be connected to them which will transfer the loads. On the other hand, if there is no plinth beam, a small concrete foundation or size stone masonry can be constructed. Roof beam or slab is used to support the stairs at the top, which restricts the movement of stairs.
3) Building the Framework for Stairs
The most important step when building stairs is to use a proper framework. For example, the angle of flight and the dimensions of thread and riser are all to be properly checked. When constructing stairs that are attached to a wall, the line of flight and the thread and risers are marked on the wall for proper fixing of shuttering or framework.
For concrete stairs, wooden boards are used to support the weight of the concrete and they must be at least 2″ thick. The whole structure of the stairs must be supported by 4×4 posts, and the wooden boards are used to create the steps. They are fastened with screws to the lateral structure of the stairs.
4) Steel Reinforcement for Concrete Stairs
Concrete stairs are reinforced with steel bars so as concrete loads are poured, they are able to be transferred to the ground. the number of steel bars and size of them is calculated by an expert and depends on the size of the loads being poured on the stairs. The steel reinforcement bars are placed in the formwork with the proper amount of spacing.
5) Pouring of Concrete for Stair and Step Construction
The pouring of concrete into the formwork is started from the bottom and worked up to the top. The concrete mix plays a critical role in the strength and durability of the stairs. Standard mixes used for stairs consist of 3 parts cement, 2 parts sand, and 4 parts gravel and water. When pouring the concrete, it’s recommended to use a concrete vibrator to fill the gaps of the stairs and to avoid a honeycomb formation.
The pouring must be carried out with patience and attention to detail. Sudden movements can mess up the alignment of the formwork and can even collapse it. Pouring the concrete ceiling and the stairs on the same day is recommended to create a strong bond between the two components.
6) Removing the Formwork
It normally takes 21 days for stairs to dry out completely after concrete has been poured. Therefore, the formwork is removed after 21 days. Proper curing is done during these 21 days to prevent cracks in the stairs from thermal expansion. A hammer and crowbar are used to remove the formwork. Patience is key when trying to avoid damage to concrete and the edges of the stairs.
7) Finishing of Concrete Stairs
Stairs can be finished in many ways once the formwork is removed. Stairs can be finished using trowel or float to give a concrete finish, or cement tiles and granite can be installed to provide a more aesthetic finish to the stairs.