Retaining Walls & Level Changes in Godalming

Why Retaining Walls Fail in Godalming

The most common causes of retaining wall failure include:

• Poor or absent drainage behind the wall
• Shifting clay soils (very common in Witley and Milford)
• Incorrect block or sleeper installation
• Inadequate footing depth
• Pressure buildup from saturated soil

Almost every retaining wall failure we repair is driven by drainage and ground movement rather than the visible facing material. Our pages on subsidence, drainage & paved surface longevity and tree roots & clay movement explain how local soils behave over time.

Correct Structural Build-Up for Retaining Walls

All walls supporting ground should follow fundamental engineering principles:

1. Footings & Foundations

• Concrete footing typically 450–600mm wide, sized to suit wall height and loads
• Depth adjusted for local ground conditions, frost and clay movement
• Heavier and higher walls may require reinforced footings or stepped foundations

2. Wall Construction

• Structural blockwork (hollow core or solid) for strength
• Concrete-filled hollow blocks for higher or more heavily loaded walls
• Brick or stone facing to match Godalming character homes
• Sleepers for lower-level terracing and informal areas

3. Drainage Behind the Wall

This is the most critical element:

• Perforated 100mm land drain at the base of the wall, falling to a safe outlet or soakaway
• Clean drainage stone backfill (not clay or topsoil)
• Geotextile membrane to prevent silt ingress and clogging
• Weep holes or gravel panels for moisture relief on suitable wall types

4. Backfill Control

• Backfill compacted in layers, not tipped in one go
• No organic material behind walls (no turf, roots or rubbish)
• Carefully graded to avoid unnecessary downward pressure and localised loading

Common Retaining Wall Types in Godalming

1. Block & Rendered Structural Walls

• Strongest type for larger level changes
• Can be waterproofed and rendered for a clean, modern look
• Ideal for Busbridge slopes, Frith Hill and multi-level gardens

2. Sleeper Retaining Walls

• Cost-effective for smaller terraces and raised beds
• Minimal visible concrete
• Great for Milford, Witley and rural fringes
• Works well alongside lawn and lawn drainage improvements

3. Stone or Brick-Faced Walls

• Perfect for character homes in central Godalming and Charterhouse
• Traditional appearance with modern structural strength behind
• Can be coordinated with front driveways and rear terraces

4. Gabion Baskets

• Excellent drainage and flexibility where soils move
• Industrial/rustic look that suits certain modern or rural schemes
• Useful where ground stability is a concern or access for heavy footings is limited

Multi-Level Gardens & Terracing

Many gardens in Godalming are naturally sloped. Terraces can transform steep, unusable ground into safe, flat, beautiful spaces.

We create terraces for:

• Seating areas and outdoor dining
• Lawn sections and play spaces
• Outdoor kitchens and entertaining zones
• Raised beds and planting terraces

Terraces are usually planned alongside overall garden drainage and any new patio areas, so levels, steps and water management are all considered together.

Steps & Garden Access

Safe steps are essential when changing levels. Poorly designed steps cause falls, narrow treads and awkward movement around the garden.

We construct steps using:

• Porcelain treads and risers to match new terraces
• Natural stone (Yorkstone, sandstone) for traditional properties
• Brick or blockwork cores with stone or porcelain facings
• Wide-format garden access steps with comfortable rises and goings

Engineering for Clay Soil Movement

Godalming’s clay expands and contracts with weather cycles, particularly in:

• Witley
• Milford
• Hambledon
• Farncombe borders

Walls in these areas may require:

• Stronger and deeper footings
• Enhanced drainage and controlled backfill
• Movement joints where long runs of wall are built
• Reinforced blockwork cores and, in some cases, engineer input

Where structures, drives or buildings sit near retaining walls, we can work alongside your engineer to build to a specified design.

Frequently Asked Questions

How high can a retaining wall be without engineering?

As a very rough rule of thumb, walls approaching or exceeding 1 metre in height, or carrying additional loads such as driveways, patios or buildings, should be treated with caution and may need structural design. Walls near boundaries or public highways can also trigger additional rules. Our planning and permissions guide for Godalming gives a helpful overview.

Do retaining walls need planning permission?

Many rear garden walls are covered by permitted development, but walls near roads, public footpaths or front elevations may require consent. Significant level changes, or works in conservation areas, can also require extra checks.

Do you handle disposal of old walls and spoil?

Yes. We remove old brick, concrete and sleepers, and organise skips or grab lorries as required. All material is disposed of responsibly in line with our waste & skip policy.

How much do retaining walls cost?

Costs depend on height, length, access, ground conditions and finish (sleeper, rendered, stone-faced etc.). Our Godalming landscaping costs 2025 guide gives realistic ballpark figures for structural garden work, patios and driveways.

Which areas of Godalming do you cover?

We cover Godalming town, Milford, Farncombe, Busbridge, Charterhouse, Hurtmore, Witley, Hambledon, Chiddingfold and the surrounding Surrey Hills.

Need Structural Garden Work in Godalming?

We design and build safe, long-lasting retaining walls and terraced gardens across the whole Godalming area, often as part of wider complete garden rebuilds.

If you have an existing wall you’re worried about, or are planning new level changes, we can visit, assess the site and suggest a practical, long-term solution.

Request a retaining wall & levels survey

Godalming Landscaping Knowledge Hub

Explore all of our in-depth landscaping guides for Godalming, Milford, Farncombe, Busbridge, Charterhouse, Witley, Hurtmore, Hambledon and the surrounding Surrey Hills:

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