Staircase Structural Details

Staircase Structural Details

So there was a case where a certain client wanted slab less stepped staircase over a conventional one. So I try to compile the structural details of major types of RCC staircase in practice today and write about their construction details. 

All these are from some of my projects down the lane. And as you may know the type of staircase used reflects the type of client.

Lets start with the simple and the most common type of stair case, the one with the waist slab. The bottom reinforcement resists the tension and top reinforcements on the ends connects the flight to the slab. This is probably the most efficient staircase design.

Reinforcement of simple staircase with waist slab

The next type of staircase are slabless staircase or stepped staircase which are not as efficient in terms of reinforcement, workmanship and load transfer but it makes up for all those in aesthetics. Here is the reinforcement detail of the simple slabless staircase. The staircase slab thickness can be safe in 5" too but in this case it is 6" mainly to allow for making a somewhat workable stirrups. However the thickness will increase with increase in length of flight.

Slabless or Stepped Staircase

Then there is the staircase of third type, the spiral one. This is for those who have lots of money and like to show it off. It feels odd thinking why would any one choose spiral staircase over normal staircase from the functional perspective. Like always it's a choice between function and looking good. It is neither comfortable to walk, nor functional (has to be single flight to look good) and difficult to built. Here the reinforcements are necessary on both top and bottom. The top reinforcement here to resist the moment.

Spiral Staircase Structural Detail