1. Stone stairs
In the pre-reinforced concrete era, stairs were often made of stone. The steps forming the flights were typically carved from a single stone block, one piece at a time with varying profiles.
The most common type is the block, i.e. (that is!) simple rectangular or wedge-shaped steps. The block concept has the steps resting on each other to create a stepped surface above and below. A significant advantage of the wedge cross-section was that only the walking surface was stepped, while the bottom part was flat. The block steps can be made with or without a groove, while the wedge-shaped stairs are almost exclusively made with a groove to achieve a perfect bottom flat surface. In addition to the two most common types, several unique profiles have emerged over time. Their use was primarily aimed at saving materials and reducing construction weight beyond possible aesthetic benefits.
Stone (and, later, terrazzo) steps were often designed as cantilevered stairs or supported by a wall, beam or vault. Both cantilevered and wall-supported stairs require at least 38-centimetre thick load-bearing brick wall. For a cantilevered stair, the minimum embed should be 15 centimetres, and the maximum cantilevered flight width should be approximately 120-130 (120 to 130!) centimetres. For stairs supported at both ends, a minimum of 8 centimetres bearing on the supporting masonry is sufficient, and the flight’s width can be several metres.
2. Wooden stairs
Wooden stairs are typically used in apartments and family houses, but many historical and modern examples exist of community use. In modern practice, wooden stairs are precision joinery; the two most common solutions being stairs built between or on top of stringer planks. The stringer planks are typically 50-60 millimetres thick, and the wood stair treads are 40-50. In case of the first option, the treads are built (carved) into the stringer plank with 20-25 millimetre deep grooves for the tread and riser boards, which are glued into place. It is also necessary to reinforce the structure in places, through tie bars placed under the treads. During the other option, the treads are laid on stepped and notched stringer planks and are fastened with pins or hidden screws.
3. Concrete stairs (add the title!!!)
Monolithic reinforced concrete stairs
We simultaneously build the different parts of the monolithic reinforced concrete stairs and ramps on-site, from the rebar installation to the formwork and concreting. For wall-supported structures, a stepped, reinforced ring beam is made on the wall together with the flight of stairs. In the case of a beam support, the stringer can overrun the upper and lower connecting lines of the steps, either upwards or downwards, or both up- and downwards.
The connection between the flight of stairs and the landing can be with or without a stringer. The latter is considered the more aesthetic solution. To achieve an accurate and beautiful finish, the design of the turning line and the application of the resulting flight and landing platform thicknesses are necessary.
Precast reinforced concrete stairs:
Precast reinforced concrete stairs are individually sized and non-mass produced. The elements: the supporting beam, the landing, and the flights are lifted into place by a crane. The great advantage of this construction method is that the prefabricated structures can be loaded immediately after lifting, but constructing the connecting structures requires high precision.
4. Metal stairs and ramps
Metal staircases are usually custom-built, metalwork structures. In the case of straight-flight stairs, I, C and (or!) U-shaped steel sections are used as struts. Between them, 5-7 millimetres corrugated steel sheet treads can be placed by welding or bolting. Of course, combinations with other materials, such as wooden treads, are also common.
Spiral stairs can also be easily made of steel. One way of doing this is to attach metal treads to the central steel column in a cantilevered way. Another solution is to fix the steps to a steel stringer following the curve on the outer side of the spiral line.