Garden Design and Landscaping as Part of a London Renovation

In most London renovation programmes, the garden is treated as a separate project to be undertaken after the house is complete. This is a mistake that costs clients time, money, and — in some cases — forces compromises that cannot be undone.

Here is how to think about garden design and landscaping in the context of a major residential renovation.

Why the garden cannot be an afterthought

Services. External drainage, water supply, irrigation, lighting, and power all need to be installed at specific points in the construction programme — typically during groundworks. If services routes are not agreed before the house renovation begins, they must either be retrofitted (expensive, disruptive) or routed in suboptimal ways that compromise the garden layout.

Structural loadings. If the garden is over a basement, the slab has been designed to carry specific loads. If the garden design calls for raised beds, a water feature, or a significant tree, the slab must be capable of taking the additional load. This must be designed before the slab is poured — not when the landscaper arrives.

Access for plant delivery. Large specimen trees and mature shrubs must be craned or walked in through specific access points. These access points must be left available until after planting is complete. If the renovation closes off access routes before planting happens, the garden design must use smaller plants — a significant compromise.

Levels and drainage. The relationship between the house floor level, the garden terrace level, and the natural ground level must be resolved during the main renovation. Poor drainage is one of the most common garden problems in London properties; it is very much harder to address after everything is built.

Starting the garden design process

The garden designer should be appointed while the main renovation is in the design phase — not after construction is complete. The practical reason is that the garden designer needs to inform:

• —Services routes and locations
• —Drainage strategy
• —External terrace levels and finishes
• —Any structural provisions required
• —Access strategy for planting

Many clients resist this because garden design feels like a discretionary second phase. In practice, the first phase of garden design work (site analysis, concept, outline layout) overlaps naturally with the early stages of house design and costs a relatively small fraction of the total garden budget.

Garden design and planning permission

External works are generally permitted development and do not require planning permission. Exceptions:

Trees with Tree Preservation Orders (TPOs): Any works to a TPO'd tree — including pruning, root work, or removal — require prior approval from the LPA. Any root protection zone of a TPO'd tree that might be affected by excavation or construction must be identified and managed. A competent arboricultural consultant can advise.

Listed building and conservation area considerations: In conservation areas, permitted development rights for garden structures (outbuildings, walls, garden buildings) are more restricted than elsewhere. Planning permission is required for walls over 1m high adjacent to a highway and over 2m elsewhere, and for garden buildings in the curtilage of listed buildings.

External lighting: Permitted development generally covers private garden lighting, but floodlighting that affects neighbours or the street environment can require permission.

What a London garden renovation involves

A serious garden renovation at a high-specification London property typically includes:

Structural works: Terrace construction, steps, boundary walls, drainage. This is construction work, not landscaping — it requires structural design and must be carried out by proper construction contractors, not just landscaping companies.

Irrigation: Automated drip or spray irrigation is standard at the luxury end. It requires a water supply connection, a control system (often integrated with the house building management system), and a design that matches the planting scheme.

Lighting: External lighting at high-specification properties is a designed element, not an add-on. A lighting designer who works in landscape contexts can create something significant. Key principles: light the plants and surfaces, not the sky; use warm colour temperatures (2700–3000K); avoid visible fittings from the house.

Planting scheme: The quality of planting makes the single largest difference to a garden's long-term character. The three dimensions of quality are: plant size at installation (larger = more immediate impact, more expensive, more difficult to install), plant quality (container-grown vs field-grown, nursery quality), and maintenance plan (a great garden at installation will look mediocre in five years without a proper maintenance programme).

Hard landscaping materials: The choice of paving material for a London garden should be considered in the context of the house. Pale Portland stone that reads beautifully against a white stucco facade looks less convincing against red brick. Reclaimed York stone has a warmth and texture that suits period properties. Porcelain pavers are practical and consistent but can read as cold. Granite setts are traditional and durable. The material should be specified together with the exterior of the house.

Roof terraces

Roof terraces present a specific set of constraints. Loading is almost always limited — typically 1.5–2.0 kN/m² live load, which restricts the depth of planters, the weight of paving materials, and what can be grown. Drainage is critical — a waterproofed roof terrace with inadequate drainage will fail. Irrigation must be piped in and controlled carefully to avoid overwatering.

Roof terrace design should be carried out by a designer experienced with the specific constraints of planted roofs. The planting palette must be chosen for exposure (wind, sun) and weight; the structure must be inspected before any loads are applied.

Budget guidance

Garden and landscaping budgets for London properties vary enormously. Indicative ranges:

Maintenance costs post-installation typically run at 10–15% of the installation budget per year for high-specification planted gardens.

ASAAN's approach

ASAAN manages the structural and services elements of garden renovations as part of the main renovation programme, coordinating with landscape architects and garden designers appointed separately or introduced through our network.

If you are planning a renovation that includes significant garden works, contact us to discuss how to integrate the two programmes.