Quick answer: An RCC staircase is a stair cast in reinforced cement concrete: steel bars inside concrete. In homes the tread is usually 220–250 mm wide and the riser 150–180 mm high. The main types are waist slab, folded plate and cantilevered stairs, cast in place or precast. It is strong, fire-resistant and long-lasting, but heavy and slow to build.
A staircase links the floors of a building and is used many times a day, so its proportions matter as much as its strength. Stairs are built in wood and steel as well, but reinforced cement concrete is by far the most common choice in Indian homes and commercial buildings.
What is an RCC staircase?
An RCC staircase is cast in reinforced cement concrete. Steel bars take the tension and concrete takes the compression, and together they form one solid element tied into the beams and slabs of the building. It carries heavy loads and lasts as long as the structure itself.
RCC staircase parts and standard dimensions
Knowing the parts of a stair helps you read the drawing and check the work on site. An RCC stair is designed like a sloping RCC slab, with these components:
- Tread: the flat part you step on. In homes it is usually 220–250 mm wide.
- Riser: the vertical part between two steps. It is around 150–180 mm high.
- Landing: a level platform between two flights. It gives a place to rest or change direction.
- Support beams or walls: these carry the stair at the floor and landing levels.
- Railing and finishes: added for safety and appearance.
The structural design follows IS 456:2000, the Indian Standard for plain and reinforced concrete. A shallow riser with a wide tread is easier to climb; a tall riser with a narrow tread saves space but is tiring and less safe, especially for children and older people.
Types of RCC staircase
By structural form
- Waist slab staircase: the steps sit on a sloping slab. This is the classic form, neat and easy to build and maintain.
- Folded plate staircase: the treads and risers form the structure at a uniform thickness, so the underside has a zig-zag profile. It is a modern look and works in compact spaces.
- Cantilevered staircase: each step is anchored on one side only and appears to float. The support must be a properly designed RCC wall or beam.
By casting method
- Cast in-situ: concrete is poured on site over fixed formwork. It allows a custom design to suit any plan.
- Precast: steps and landings are made in a factory and brought to site. It saves time and gives consistent quality.
By layout
RCC can be cast in any of the usual layouts: straight, dog-legged, L-shaped or open well. The dog-legged staircase is the most common in houses because it fits into a compact stair room.
How is an RCC staircase built?
- Marking: the floor-to-floor height is divided into equal risers and the steps are marked on the side walls.
- Formwork: a sloping soffit of plywood or planks is fixed and propped, with riser boards for each step.
- Reinforcement: main bars are laid along the slope with distribution bars across them, on cover blocks, and anchored into the supporting beams and landing as shown in the structural drawing.
- Concreting: the waist slab and steps are poured together, starting from the bottom, and vibrated so the concrete is dense.
- Curing: the stair is kept wet so the concrete gains its strength.
- Removing the props: the supports stay in place until the concrete is strong enough to carry itself.
- Finishing: the steps are finished in tile, stone or wood and the railing is fixed.
What to check on site
- Equal risers: measure them before concreting. One odd step, usually the first or the last, is the most common cause of tripping. Allow for the thickness of the floor finish at both ends.
- Bars as per drawing: check the bar size, spacing and the anchorage at the landing before the pour.
- Cover blocks: the steel must not rest on the formwork.
- Headroom: check the clear height under the flight or beam above, so nobody has to duck.
- Landing width: it should not be narrower than the flight.
- Railing fixing: decide how the railing will be fixed, and leave inserts or pockets if needed, before the steps are finished.
Pros and cons of an RCC staircase
| Pros | Cons |
| Very high strength and load capacity | Heavy structure adds load to the building foundation |
| Long-lasting and low maintenance | Labour-intensive and time-consuming to build |
| Fire-resistant | Limited design flexibility for curves or unusual shapes |
| Can span large areas without many supports | Higher labour costs |
| Takes many finishes: tile, stone, wood or exposed concrete | Precast option can be expensive |
| Good for outdoor use |
Why choose RCC for a staircase?
- Strength and safety: it carries heavy traffic and loads, which makes it suitable for tall buildings and public spaces.
- No rot: unlike wood, it is not damaged by termites or damp, and the steel is protected inside the concrete.
- Fire resistance: it does not burn, so the stair stays usable as an escape route.
- Choice of finish: leave it raw for a modern look or clad it in tile, stone or wood.
RCC stairs for outdoor use
RCC is the right material for outdoor steps. It resists weather, needs little care and lasts long. Outdoors, give each tread a slight slope so water runs off, and choose a rough or flamed finish that stays safe when wet.
Points to remember
- Curved RCC stairs are hard to form unless special methods such as ferrocement are used.
- Cast in-situ work needs skilled labour and more time.
- Precast stairs are quick to install but cost more.
- The weight of the stair has to be allowed for in the structure and foundation, so the staircase should be part of the structural design from the start.
- Do not shift the staircase position or cut into a cast stair later. Both affect the structure.
For a house, have the architect fix the stair layout and the structural engineer detail the reinforcement before work starts.
Related guides
The bars inside the stair are covered in our guide to reinforcement in construction, and the stair sheet is one of the drawings explained in structural (GFC) drawings. After casting, the stair must be cured properly; see the types of concrete curing. If you are considering factory-made flights, read what precast concrete is, and for the finish, which colour granite is good for stairs. Staircases are built as part of the structure in our house construction service.
Frequently asked questions
What is the standard tread and riser size for an RCC staircase in a house?
In homes the tread, the flat part you step on, is usually 220–250 mm wide. The riser, the vertical part between two steps, is around 150–180 mm high. Every riser in a flight should be the same height.
What is a waist slab staircase?
It is the most common RCC stair. The steps sit on a sloping reinforced concrete slab, called the waist slab, which spans between the floor and the landing. The underside is a plain sloping surface. It is neat, and easy to build and maintain.
What is a folded plate staircase?
A folded plate staircase has no sloping slab under the steps. The treads and risers themselves form the structure, at a uniform thickness, so the underside shows the same zig-zag profile as the top. It gives a modern look and needs careful reinforcement detailing.
Which is better, a cast in-situ or a precast RCC staircase?
Cast in-situ stairs are poured on site and can be shaped to any layout, but they need skilled labour and more time. Precast stairs are made in a factory, install quickly and have consistent quality, but they cost more.
What are the disadvantages of an RCC staircase?
It is heavy and adds load to the structure and foundation. It is labour-intensive and slow to build, curved shapes are difficult, labour costs are higher, and the precast option can be expensive.
Is an RCC staircase suitable for outdoor use?
Yes. RCC resists weather, needs little care and lasts long, so it is the usual choice for outdoor steps. Give the treads a slight slope and a non-slip finish so water does not stand on them.
