Groundwork Contractors in the UK

Finding a good groundwork contractor in the UK

Groundworks is everything that happens before a building goes up and everything under and around it once it has: excavation, foundations, drainage, concrete slabs, retaining walls, driveways and paths, kerbs, ducting for services and the levelling of a site. It is the part of a project that is buried and forgotten if it is done well and expensive to fix if it is not. Groundworkers work for builders on extensions and new homes, for developers on whole sites, for councils and utilities on roads and drains, and directly for homeowners on driveways, drainage and garden structures.

The work is skilled and heavy. A good contractor digs to the depth building control asks for, deals with what the ground turns out to be — clay, water, roots, old drains — and pours concrete, lays drains to fall and builds up hardcore and sub-bases that will not move. They own or hire the diggers, dumpers and compactors, know where the services run before the bucket goes in, and leave a site ready for the next trade with the muck taken away.

Groundworks is not licensed, but the standards are: foundations and drainage are inspected by building control, drain connections to the sewer need the water company's consent, and the contractor should be insured and, on any site with plant, competent to run it. The listings here show each groundwork contractor's reviews, the kinds of jobs they take, opening hours and contact details, so you can see who works in your area, who does domestic as well as site work, and whose builders keep hiring them.

What groundwork contractors do

Foundations and slabs: strip, trench-fill, raft and piled foundations for extensions, garages, garden rooms and new houses, with the concrete slab and damp-proof membrane above.

Drainage: new foul and surface-water drains, soakaways, connecting to the sewer, repairing collapsed or root-damaged runs, land drainage for waterlogged gardens, and CCTV surveys to find the fault first.

Driveways and hard landscaping: excavation, sub-base, edgings and kerbs, block paving, tarmac, resin or concrete, patios, steps and retaining walls, with drainage to keep water off the house.

Site work: clearing and stripping, reduced-level digs, muck-away, ducting for gas, water, electric and broadband, temporary roads and hardstanding.

Civil engineering: kerbing and road works, car parks, culverts and concrete structures for commercial and public clients.

Before you book a groundwork contractor

• Have the drawings and building control requirements for foundations and drains; the contractor prices to those, not to a guess.
• Ask whether the quote includes muck-away, plant hire, concrete, sub-base and reinstating the ground, and what happens if the dig finds bad ground or water.
• For drains, ask for a CCTV survey first when the problem is a fault, and confirm they will get the water company's consent for a new sewer connection.
• Check public liability insurance and, for anything near a road or with plant, the operator competence and street-works permit.
• Ask them to check for buried services before digging and to mark the site out with you.
• Get two or three quotes on the same drawings and look at photos or a site they finished a year ago, especially for driveways and walls.

What groundworks cost in the UK

As a rough guide, foundations for a single-storey extension cost £4,000 to £12,000 depending on size and depth; a new drain run or sewer connection £1,500 to £5,000; a soakaway £800 to £2,000; a driveway dug out and finished £60 to £120 per square metre for block paving or tarmac and more for resin; a retaining wall £150 to £350 per linear metre. London and the South East are higher, and clay, water and access all push prices up.

Groundworks quotes vary with what is under the surface, so a good contractor prices what the drawings show and says clearly what an unexpected depth or soft ground would cost. Compare quotes on that basis, not the headline.