Expert Groundwork and Drainage Contractors Across the South East
CJ Groundworks provides professional groundworks, drainage and off-mains wastewater services across Sussex, Surrey and Kent. With more than 35 years of industry experience, our in-house team completes all projects with careful planning, clear communication and a high standard of workmanship.
Our services include building foundations, concrete bases, excavation, site preparation, drainage installation and repair, septic tanks, cesspits and sewage treatment plants. From the initial site assessment to excavation, installation and final reinstatement, we manage every stage of the work.
Contact us for practical advice, a site visit and a clear, no-obligation quotation tailored to your project.
/ Our Services
Groundwork, Drainage
and Off-Mains Services
From preparing a site and installing structural foundations to solving drainage problems and fitting off-mains wastewater systems, our experienced team delivers complete groundwork solutions across the South East.
Building Foundations
Create a dependable base for your extension, new building, garage or commercial structure with professionally excavated and installed foundations.
Depending on the design, ground conditions and structural requirements, our work can include:
- Strip foundations
- Trench-fill foundations
- Raft foundations
- Pad foundations
- Piled foundations
- Excavation and ground preparation
- Reinforcement and concrete placement
We work from the approved specification and coordinate with Building Control, structural engineers and other contractors where required.
Concrete Bases
We install strong, level concrete bases for sheds, garages, workshops, garden rooms and other outbuildings. Each base is prepared around the dimensions, ground conditions and load requirements of the proposed structure.
A typical installation can include excavation, a compacted sub-base, damp-proof membrane, reinforcement, optional insulation and accurately placed concrete with a smooth or brushed finish.
Our team manages the preparation and pour from start to finish, leaving a durable base ready for the next stage of construction.
Each base includes a Type 2 sub-base, damp-proof membrane, and optional insulation for long-lasting performance. Our bases are laser-levelled, reinforced, and completed to a smooth or brushed finish, providing the perfect foundation for your structure.
Site Preparation & Excavation
Prepare your site safely and efficiently for construction, landscaping, drainage or utility work. Our team provides controlled excavation and ground preparation for domestic and commercial projects.
Services can include:
- Site clearance
- Excavation and reduced-level digging
- Soil grading and levelling
- Ground stabilisation
- Trench and duct excavation
- Muck-away and responsible waste removal
- Backfilling and compaction
We assess access, ground conditions, waste volumes and the next stage of construction before work begins.
Drainage Solutions
CJ Groundworks installs, repairs and upgrades foul-water and surface-water drainage systems across Sussex, Surrey and Kent. We investigate the cause of the problem before recommending the most appropriate solution for the site.
Our drainage services include:
- Foul and surface-water drainage
- Drain repairs and replacement
- CCTV drain surveys
- High-pressure drain jetting
- Soakaways and French drains
- Channel drainage
- Drainage for extensions and new developments
Every installation is planned around the site layout, ground conditions, water flow and applicable drainage requirements.
Off-Mains Drainage Systems
For rural properties and sites without a mains sewer connection, we install and replace correctly specified off-mains wastewater systems. Our team can assess the property, ground conditions, occupancy and discharge requirements before recommending a suitable solution.
Why Choose CJ Groundworks?
Experienced Groundwork Contractors You Can Rely On

35+ Years of Experience
A long-standing reputation built on expert workmanship.

In-House
Team
No subcontractors; we keep all trades under one roof.

Fully Insured &
Guaranteed
No subcontractors; we keep all trades under one roof.

Compliant &
Certified
All works carried out to UK building regs and environmental standards.

Local
Expertise
Proudly serving Sussex, Surrey & Kent.
Our Service Area
Groundwork Services Across Sussex, Surrey and Kent
CJ Groundworks is based in Barns Green and covers:
- Cranleigh
- Horsham
- Midhurst
- Petworth
- Pulborough
- All surrounding areas in Sussex, Surrey, and Kent
Not Sure Which Groundwork Service You Need?
Every project begins with different ground conditions, access requirements and construction plans. Speak directly with our experienced team for practical advice on the most suitable next step.
We can review photographs or plans, discuss the work by phone and arrange a site visit where required.
/ FAQs
Frequently Asked Questions
A groundworks company prepares land for construction. This includes excavation, foundation installation, drainage, and off-mains systems. We handle both residential and commercial groundwork across Kent, Surrey, and Sussex.
Timeframes depend on project size and complexity. A small base can take 1–2 days, while a full foundation and drainage package may take a week or more. We provide clear timelines upfront.
Yes — our groundwork contractors in Kent, Surrey, and Sussex work with homeowners, builders, and developers on everything from garden offices to industrial facilities.
Absolutely. All work is covered by our 2-year workmanship guarantee and manufacturer warranties. We’re also fully insured and compliant with UK regulations.
Yes — we specialise in septic tank installation, cesspit installation, and sewage treatment plant servicing across Kent, Surrey, and East & West Sussex.
/Our Contact
Ready to break ground?
Get in touch with CJ Groundworks today to discuss your project and receive a free, no-obligation quotation. Our team is here to answer your questions and provide expert advice tailored to your needs.
Address
CJ Groundworks, Lower Batchelors, Emms Lane, Barns Green, West Sussex, RH13 0QH.
/ Our Testimonials
What clients say about us
I contracted CJ Groundworks to install a sewage treatment plant, it was a very pleasant experience dealing with Chris and his ever smiling team. The job was done professionally in time at a reasonable price. The plant is working satisfactorily for 3 months.
After calling round dozens of other contractors and hearing nothing I came across CJ groundwork's and I'm glad I did. They built a big shed base and carried out landscaping work in the garden. They fitted us in at short notice and everything was done to a brilliant standard at a fair......
CJ did a fantastic job of putting in a new foul drain for me. From first contact to completion, it has been professional, friendly and incredibly efficient. Their work is excellent throughout - the overall standard, their ethics and communication are superb. Also, they have a rare quality in being personable but respectful. I would, without hesitation, recommend them to anyone.
/ From the blog
Latest Articles

What Affects the Cost of Building Foundations?
The cost of building foundations can vary considerably between construction projects, even when the buildings themselves appear similar in size. Ground conditions, foundation design, excavation requirements, site access and the amount of concrete needed all influence the final price. For homeowners planning an extension, foundations can be one of the

How Can Poor Drainage Damage Your Property?
Poor drainage can damage a property in several ways, from persistent damp and water entering buildings to deterioration of external surfaces and, in certain circumstances, problems affecting the ground around foundations. The severity depends on where the water collects, how frequently it occurs and whether it can escape through a

When Should You Hire a Groundworks Contractor?
Knowing when to hire a groundworks contractor can make a significant difference to the success of a building project. Whether you are planning a house extension, preparing land for a new structure or installing underground drainage, the work beneath the surface often determines how smoothly everything else progresses. A professional