Paving, walls, steps and decks: how they fit into the garden

Built elements organise circulation, resolve levels and create places to spend time in. They should be thought through together with water, planting and the way the space is used.

The choice considers slip resistance, heat build-up, strength, joints and maintenance. The base and the fall matter as much as the finish.

Close to trees, the impermeable area and the rooting space need to be reconciled.

Retaining walls hold back soil and require calculation, foundations and drainage. Boundary walls or seat walls have other requirements.

Stone, concrete, masonry and mixed systems relate to the place in different ways.

The height and depth of the steps should keep a comfortable rhythm. Lighting and handrails are considered according to use and legislation.

Water should not run across the steps in an uncontrolled way.

Timber and composites need ventilation, structure and access for inspection. Expansion and ageing are allowed for.

A deck close to the ground must not block drainage or hide damp problems.

Planting softens edges and gives shade, but roots and future growth need space. Plants should not be used to hide badly finished edges.

Fewer materials, well connected, generally produce greater coherence. The choice follows the architecture without copying every interior finish.

The visible finish depends on the layer beneath. Sub-bases, bases, screeds, structures and fixings are sized for the soil and the load.

Joints absorb movement and help to organise the pattern. Edge details against buildings, trees and other materials prevent water ingress, cracks and areas that are hard to maintain.

Ramps need a gradient, width, landings and surface compatible with the use. A solution that merely meets a percentage on the drawing can still be uncomfortable on the ground.

When the length required is excessive, the organisation of the garden should be reviewed. Accessibility should not be added after the levels have been fixed.

Stone and timber show differences in colour, grain, texture and ageing. A small sample may not represent the whole batch.

The design should accept this variation when it is part of the material and define the limits of selection. Future maintenance, the availability of replacements and provenance are as relevant as the initial appearance.

Outdoor spaces are exposed to water, sun and swings in temperature. Materials change and joints accumulate wear.

Details that can be dismantled and access to services make repairs easier. A durable design does not demand a permanently new appearance; it anticipates how the material can age without losing safety or coherence.

Materials should respond to the way they will be used. Beside swimming pools, slip resistance and temperature matter; on driveways, load-bearing capacity; on steps, the regularity of the treads and legibility at night.

Guardrails, handrails and ramps are integrated into the design from the start. A technically necessary solution should not appear as an element added after all the levels have been defined.

Tree pits and edge details need to allow for growth. Bringing paving too close to the trunk reduces soil, makes watering harder and increases future conflict.

Joints and edges should also allow maintenance without damaging roots, bark or edging plants.

• How an outdoor space is built
• How to think about maintenance in the design

1. Principles of landscape construction and paving detailing.
2. Accessibility and safety regulations applicable to each scheme.