Retaining walls do serious work: they hold back tonnes of soil and water. Built well, they turn a slope into usable terraces. Built poorly, they bulge, crack and eventually fail.
Walling is at the heart of what we do. We've built four sets of walls on a steep hillside garden, rebuilt a very old wall so it became a garden feature, and restored old walls for customers across Cornwall.
Cornish walling adds character that suits the local landscape, and we combine walls with steps, patios and drainage to create complete, usable levels.
Who it's for
Steep gardens needing level terraces
Properties with bulging or failing walls
Old stone walls needing restoration
Coastal and hillside plots
What happens if it's left
The cost of getting it wrong
Bulging and cracking
Walls without drainage build pressure behind them until they move.
Collapse risk
A failing retaining wall can collapse, taking soil, patios or paths with it.
Unusable slopes
Without walls, steep ground stays steep.
Lost heritage
Old stone walls left unrepaired deteriorate quickly.
Common mistakes we see
Building without drainage behind the wall
Underestimating the load of wet soil
Patching a failing wall instead of rebuilding
Our process
How it works, step by step
01
Visit & inspection
We come out, walk the garden with you and look at access, levels, ground conditions and drainage.
02
Plan & detailed quote
We explain what the job involves and how long it will take, then put a detailed quote in writing.
03
Groundwork
Clearing, digging out, levelling and drainage. Getting this right is what makes the finished work last.
04
Build & finish
The work itself, done by Harry and the team.
05
Handover & warranty
We walk you through the finished job. Your written contract and warranty (typically 2 years) are yours to keep.
What you get
The benefits
01
Usable terraces
Slopes turned into level space.
02
Drainage built in
Pressure relieved so walls stay put.
03
Local character
Cornish walling that suits the landscape.
04
Restoration
Old walls rebuilt to become features.
05
Joined-up work
Walls, steps, patios and drainage together.
06
Warranty included
Written contract and warranty, typically 2 years.
In detail
Retaining Walls & Cornish Walling explained
“2 sets of excellent work landscaping our very steep coastline garden by Harry and Mat”
Chris Matijasevic · Google review
How retaining walls work
A retaining wall resists the sideways pressure of soil and water. Foundations, construction and drainage behind the wall all matter: drainage especially, because trapped water is what pushes walls over.
Cornish walling
Traditional Cornish walling uses local stone laid in a style that belongs in the landscape. It's ideal for boundaries, terraces and garden features that need to look as though they've always been there.
Restoring old walls
Many Cornish gardens have old walls that have slumped or partly collapsed. We've rebuilt very old walls so they became a feature of the garden again.
Terracing a hillside garden
On steep plots we combine multiple walls with steps, patios, decks and drainage. One hillside project needed four sets of walls plus new patios, decks and plumbing to sort drainage.
Planning your retaining walls & cornish walling project
Start with how you'll use the space
Before choosing materials, think about who will use the garden and when. A space for summer dining needs different sizing, shelter and access from a low-maintenance front garden or a holiday let that needs to look smart between guests. Tell us how you live and we'll shape the retaining walls and Cornish walling around it.
Look honestly at the ground
Slope, soil, existing walls, hedges and drainage all affect what's possible and what it costs. In Cornwall, many gardens are steep, rocky or exposed to the coast. We assess all of this on our first visit so your quote reflects the real job: not a best-case guess that changes once work starts.
Think about the whole garden
Retaining Walls & Cornish Walling rarely sits in isolation. It meets lawns, beds, boundaries, paths and steps. Planning these together avoids the cost of reworking levels or access later, and gives you a garden that feels designed rather than added to piece by piece.
Why Sea Green
What our customers tell us
Across 13 five-star Google reviews, the same themes come up again and again: punctuality, quick responses, professionalism, quality workmanship, detailed quotes and creative design ideas, and an ability to handle difficult sites such as steep slopes and coastal gardens.
Harry Lyall runs every job, working alongside his colleague Matt. You deal with the people doing the work, from the first visit to the finished garden, so nothing gets lost between the quote and the build.
Every retaining walls and Cornish walling job is covered by a full written contract and a warranty, typically 2 years, confirmed in writing for your specific job, and by our employer's and public liability insurance. You know what's included, what it costs and what happens if anything isn't right.
Yes, we've built four sets of walls on a steep hillside garden.
Do you restore old stone walls?+
Yes, we've rebuilt and restored old walls.
Do retaining walls need drainage?+
Yes. Drainage behind the wall is essential, and we build it in.
Can you add steps between levels?+
Yes, steps are often part of terracing projects.
How long does a wall take?+
It depends on length, height and access. We'll explain when we quote.
How much will it cost?+
Every garden is different: access, ground conditions, slope and materials all change the price. Rather than guess, we visit, talk through the job and give you a detailed written quote so you know exactly what's included before anything starts.
Is the work guaranteed?+
Yes. Every job comes with a full written contract and a warranty. The length depends on the job and is typically 2 years; we'll confirm it in writing on your quote.
Are you insured?+
Yes. We hold both employer's liability and public liability insurance.
Do you cover my area?+
We're based in Truro and work across Cornwall, including Falmouth, Penryn, Redruth, Camborne, St Austell, Newquay, St Agnes and Perranporth. If your town isn't listed, call us and we'll tell you straight away.
