STRUCTURAL ELEMENTS AND BUILDING METHODS 245 STEPS drain off precipitation water, which is achieved primarily by inclining the step towards the front edge. The incline should be 1–3%, but at least 0.5 cm per step. This not only prevents water from standing or ice from accumulating on the step, but also stops water penetrating the foundations, thus restricting damage from freezing water. In order to capture water running off higher areas, and in the case of longer stair structures, drainage gutters should be placed before the top step, and below each individual step in the case of stepped paths. > Chapter 3.11 Flights of steps that are constantly in the shade should be checked particularly carefully in terms of the material used because of the poor drying that can be expected. This applies in particular to steps in wood, metal and stone with polished surfaces, which should be used only in conjunction with antislip surface treatment. Exceptions here are roofed stairs or climatic conditions that admit different construction methods.
one flight
Fig. 3.3.5: Steps with straight and spiral flights
Fig. 3.3.6: Steps placed in front of a structure, and recessed steps
spiral staircase with well
two flights
CONSTRUCTION METHODS Staircase forms Straight steps with one or more flights are not the only staircase form. Changes in direction in the flights produce a number of forms for staircases. Such changes are produced by a landing (angled stairs) or by arranging the steps in a spiral. > Fig. 3.3.5 Steps can also be distinguished by their position in the run of walls or on the terrain, and there are also steps with and without protected sides. > Figs. 3.3.6–3.3.9 Steps without side sections on an embankment are well suited to step shapes that clearly tie into the ground at the sides (e.g. solid rectangular steps).
Loadbearing structures Steps in the open air are often constructed directly on the subsoil. The load is then transferred either over the whole area via stepped concrete slab foundations
quarter turn to the right
two flights, turning left with quarter landing
spiral newel staircase, one flight
arched spiral staircase, two flights
two flights, turning right with half landing
three flights with half landing
three-flight spiral