Many homes have gardens that slope away from the house and often these are simply grassed over. A gradient of 30 degrees to the horizontal is about as much slope as a cylinder mower will cope with, although a hover mower will tackle a 45-degree gradient; in either case, it will be hard work maintaining a beautiful lawn. A practical solution is to build a run of steps, which can also provide an interesting feature, a vantage point and a temporary resting place.
Plan your steps as a means of getting from level A to level B. Ideally, steps in a garden should be low, gentle and wide, but the materials you choose will, to a certain extent, dictate their form. Also, bear in mind the safety aspects when you build steps. Treads that are too smooth will be slippery when wet or frosty; materials that wear quickly or an unstable surface will be dangerous, and, if moss is not removed, they can be lethal. Treads on steps outdoors must not be absolutely level because they won’t shed rainwater quickly: puddles will develop that, in winter, will ice over.
The proportion of the tread (the area you stand on) to the riser (the vertical ‘back’ or height of the step) is also important. As a rough guide, construct steps so that the depth of the tread (from front to back) plus twice the height of the riser, equals 650mm (2ft 2in). For safety’s sake – and for aesthetics – never make your treads less than 300mm (1ft) deep or risers higher than 175mm (7in). Leave an overhang as the shadow cast will help to define the tread edge.
1 Prepare the site
Measure the difference in height from the top of the slope to the bottom and calculate the number of steps required. Mark the position of risers with pegs and roughly cut out the ground. Construct the risers from concrete facing blocks or bricks, allowing the treads to overhang by about 25-50mm (1-2in).
2 Lay the slabs
Lay concrete slabs bedded in sharp sand flush with the ground at the foot of the slope, or dig a trench to hold a sub-base of well-compacted hardcore and a 100-150mm (4-6in) concrete base to support the first riser. Construct the first riser using normal bricklaying methods and check alignment with a spirit level. Fill behind the riser with compacted hardcore until it is level, and then lay the tread on a bed of mortar. Using the spirit level as a guide, tap down the tread so it slopes very slightly forwards to shed water. Measure from the front edge of the tread to mark the position of the next riser on the slabs and construct the step in the same way.
3 Setting the final tread
The final (topmost) tread should be set so that it is flush with the area at the top of the flight of steps. If you have to excavate some of the soil from the top, dig deep enough for a hardcore sub-base and concrete base on which to lay the tread slabs to make this tread secure.
Where power cables supply outdoor lights, water features, or power to an outbuilding, they should be run through an impact-resistant plastic conduit that is laid in a trench lined with finely sifted soil or sand. Lay the conduit then carefully fill the trench.