Before the Sub-Base Goes Down: The Services You Only Get One Chance to Bury
Photo: open groundworks trench with ducting pipes laid before paving, via www.ucleeds.ac.uk
There is a short window in every paving project where the ground is open. The old surface is up, the levels are set, and nothing has been compacted yet. Two days later the Type 1 goes down, the whacker plate comes out, and that window shuts for the next twenty years.
We've lost count of the number of times a customer has asked, a fortnight after handover, whether we can "just run a cable under there" for a socket by the back door. The honest answer is that we can, but you won't like what it involves.
The bit nobody takes a photo of
Groundworks are unglamorous. Nobody posts a picture of a trench. But the decisions made in that trench cost pennies compared to the ones made after the paving is finished, because after that point every service means lifting, cutting, chasing or drilling.
If you're at planning stage, treat this as the cheapest afternoon of the whole job.
Power: sockets, lights and the shed at the end of the garden
Think about where you'll actually want electricity, not just where you want it this summer.
- A double socket on the patio wall for a mower, a pressure washer or a November light display
- Low-level lighting along a path or step edge, which needs a feed and often a transformer somewhere accessible
- A supply to a shed, garage or garden office
- A feed to a water feature pump if one is on the cards
Armoured cable is the usual choice outdoors because it can take a spade through it without anyone getting hurt. Cable depth and protection matter, and it should be signed off by a qualified electrician rather than buried hopefully by whoever is on the digger.
One trick worth the extra few pounds: bury a 25mm duct with a draw rope inside, even if you're not sure what it's for yet. It costs almost nothing in an open trench and saves an excavator later.
Water: taps, hoses and irrigation
If you've ever dragged a hose around a corner and through a flowerbed, you already know why this matters.
A blue MDPE water pipe run in a duct from the house to the far side of the patio, terminating in an outside tap near the planting, is one of the best value items in the whole groundworks package. Add an isolator inside the house so you can drain it down before the first hard frost.
If you're planning raised beds, a greenhouse or a run of new borders, it's also worth thinking about drip irrigation now. Laying a line to a tap and a small manifold is easy while the ground is open and genuinely awkward afterwards.
The EV charger question
Most people buying a driveway in 2026 have at least thought about an electric car. Fewer have thought about the cable route.
The charger itself can be chosen later. The route from the consumer unit to the parking position cannot. That means a duct from the house to the point where the charger will eventually sit, sized generously, with a pull cord, and a spare draw line for good measure.
Decide roughly where the car will park, decide which wall the charger will hang on, and get the duct in. A qualified electrician can do the final connection and certification whenever you're ready.
Drainage you'll wish you'd added
Water is the thing that ruins paving, and drainage is the thing people cut first when the quote creeps up.
While the ground is open, consider:
- A channel drain across the garage threshold or the low point of the drive
- A rodding eye on any run that might one day block
- A soakaway or connection for a downpipe that currently dumps onto the drive
- A gully where water naturally pools, rather than where it's convenient to put one
If your drive slopes towards the house, this isn't optional. It's the whole ballgame.
Data and the garden room
If there's any chance of a garden office, a cabin or even a decent wifi signal at the bottom of the garden, run a data duct while you're there. A bit of Cat6 in a conduit costs very little at this stage and is a nightmare to add later without clipping cable to a fence.
Why retrofitting stings so much
The pattern is always the same. A few hundred pounds at groundworks stage, or a four-figure job later. Lifting and relaying a section of patio means the paving comes up, the bedding is broken out, the sub-base is dug through, the service is laid, then everything is rebuilt and re-pointed, and you're left hoping the replacement stones match the originals after two summers of weathering.
Chasing a cable up an external wall means a scar in the render and a decorator. Getting a pipe under a finished drive usually means a moling contractor or a very long discussion about a trench.
The list to take to quote time
Before you sign anything, put these questions in writing:
- Have we agreed where outdoor sockets, taps and lights will go?
- Is there a duct and draw cord to the parking position for a future charger?
- What's the drainage plan, and is there a rodding eye on every run?
- Are we burying any spare duct for future use?
- Who is signing off the electrical work?
- Has the water pipe got an internal isolator?
A decent contractor will welcome those questions. It means the job is being planned rather than improvised, and it protects you from a very expensive conversation two summers from now.
