Stairs

A stair means a series of at least three steps, also called a flight of stairs, A stair can form the link between two storeys of a building. in Rural Building we are only concerned with one storey buildings, so the stairs are usually only needed up to the level of the floor of the building, which is normally not much higher than 60 cm above ground level.

TECHNICAL TERMS:

Fig. 1 shows the parts of a staircase.

TREAD: The tread is the horizontal part of the step (a).

RISER: This is the vertical part of a step (b).

GOING: This refers to the width of the tread (c). The "going" of a flight of steps is the sum of the "goings" of all the steps of the flight.

RISE: This is the vertical distance between two treads, equal to the height of the riser (d).

REQUIREMENTS

The short flights of stairs we make in Rural Building are usually built with sand-crete blocks or are cast out of concrete. Regardless of the materials and the method of construction, the steps must be all the same height and the same width. A staircase with steps of different sizes is likely to cause accidents.

The rise of the steps is usually 15 cm (approximately) and the width of the tread, the "going", is usually about 30 cm for each step.

The steps in Fig. 2 are built with sandcrete blocks, so the rise of 17 cm is convenient because it fits in with the block size. The width of the tread can be about 28 cm, or slightly more than the half-block size.

Steps cast out of concrete can have any convenient rise, but normally the rise is about 15 cm high, and the width of the tread will be approximately 30 cm. The formwork for casting the steps is shown in Fig. 3.

Plan ahead. If the steps with a 15 cm rise do not reach the right level (measure the height before you start to make the steps) either change the height of the rise (to 14, 16, or 17 cm, etc); dig out some soil before to lower the height of the whole stair; or add a foundation slab to raise the whole construction by a few centimetres to the required height.

- REMEMBER: Never make steps of different sizes in the same stair.