Retaining walls do more than hold back soil—they shape your land, prevent erosion, and create stunning outdoor spaces. Whether you’re on a sloping site in Tauranga or levelling your garden in Christchurch, a retaining wall can be the backbone of a functional and beautiful landscape.
In this guide, we’ll walk you through everything you need to know about retaining walls in New Zealand—from types and materials to council consents and costs—so you can plan your project with confidence.
What Is a Retaining Wall?
A retaining wall is a structure built to hold back soil and reshape uneven land. They’re often used to:
-Support sloped areas
-Prevent erosion
-Create level sections for gardens, driveways, or patios
-Add definition and visual appeal to landscaping
Common Types of Retaining Walls in NZ
1. Timber Retaining Walls
Affordable and fast to install, timber walls are popular in residential settings. Treated pine or hardwood posts and sleepers are used to resist moisture and decay.
Best for: Small to medium walls, garden beds, or property boundaries.
Lifespan: 15–25 years (with proper treatment and drainage)
2. Concrete Block Retaining Walls
Strong, modern, and durable. Concrete blocks can be rendered, plastered, or left exposed for a clean finish.
Best for: Larger walls, structural support, or sleek landscape designs.
Lifespan: 50+ years with minimal maintenance.
3. Stone or Rock Retaining Walls
Natural stone offers rustic charm and blends beautifully with NZ’s landscapes. Dry-stacked or mortared options available.
Best for: Decorative purposes, garden edging, or high-end landscaping.
Lifespan: Very long—often 50+ years.
4. Gabion Retaining Walls
Wire cages filled with rocks or stones, offering a modern, industrial look. They’re excellent for drainage and eco-friendly builds.
Best for: Erosion control, waterfronts, or creative landscaping.
Lifespan: 40–60 years with galvanised cages.
Do You Need Council Consent in New Zealand?
Yes—sometimes. Local councils typically require consent if your wall is:
✅Over 1.5 metres high
✅Near a boundary or building
✅Supporting a driveway, building, or another load
✅Affecting public safety or drainage
Pro tip: Always check with your local council before building. A professional contractor can help you manage the consent process and ensure your wall complies with NZ Building Code standards.
How Much Does a Retaining Wall Cost?
Costs vary based on materials, height, access, and site conditions. Here’s a rough guide for New Zealand:
| Type | Approx. Cost per Metre |
| Timber | $300 – $500 |
| Concrete Block | $500 – $900 |
| Stone/Rock | $600 – $1,200+ |
| Gabion | $450 – $800 |
Note: These are general estimates. Always get a detailed quote from a trusted local contractor.
Why Drainage Matters
Drainage is the unsung hero of any retaining wall. Without proper drainage, water can build up behind the wall and cause pressure, movement, or collapse.
Every well-built wall should include:
✅Drainage scoria or gravel
✅Drainage pipes (ag-pipes)
✅Waterproofing membranes for block walls
✅Weep holes for pressure release
Design Tips for NZ Homeowners
✅Match the landscape: Choose materials that complement your home’s exterior or garden.
✅Think long-term: Investing in higher-quality materials can reduce maintenance over time.
✅Consider lighting: Add solar lights or recessed LEDs for safety and style.
✅Add planting: Soften the look of hard materials with shrubs, grasses, or vines.
Should You DIY or Hire a Pro?
Small timber garden walls can be DIY-friendly, especially if they’re under 1 metre high. But for anything structural, higher, or near boundaries—it’s best to leave it to the pros. A qualified contractor will:
✅Ensure proper footings and drainage
✅Handle engineering and council requirements
✅Save you time, money, and stress in the long run
Final Thoughts
Retaining walls are an investment in your property’s structure, safety, and style. Whether you’re adding a garden border or managing a serious slope, the right wall makes a big difference.
If you’re in Tauranga (or anywhere in NZ) and need advice or a quote on building a retaining wall, we’d be happy to help. We design and build walls that are made to last—with a finish you’ll be proud to show off.