Most people choose a driveway from a photograph. That is a fair place to start, but the photograph only shows the top forty or fifty millimetres of the job. Everything that decides whether the drive still looks like the photograph in ten years is buried underneath it.
Here is how the three common surfaces actually behave, and what has to happen below them.
Block paving
Concrete or clay blocks on a sand or grit laying course, over a compacted stone sub-base, with the whole lot held in by edge restraints bedded in concrete.
It takes point loads well. Individual blocks can be lifted and put back if a service needs digging up or if something stains, and you get a lot of freedom on pattern and colour. Of the three, it is the one most likely to be lifted and reused rather than dug out and skipped.
Against that: the joints need sand kept in them, and weeds and moss will find any joint that has run dry. The surface is also only as flat as the base under it. Rutting where the car wheels sit is nearly always the sub-base settling, not the blocks failing.
Edge restraint matters more than most homeowners expect. Blocks work by interlock, holding each other in place through friction. Lose the restraint down one side and the paving spreads, the joints open, and it goes downhill from there.
Resin
Two different products get sold under this name, and they are not comparable.
Resin bound is aggregate mixed with resin in a forced action mixer and trowelled out as a single layer. Every stone is coated and locked in. The finish is smooth, there are no loose stones, and on the right base it lets water through.
Resin bonded is resin spread onto a base with loose stone scattered over the top. It gives a grippy, gravel-look finish, but the stone sits on the surface rather than in it, some of it will come away, and it does not drain through.
If somebody quotes you for "a resin drive", ask which one. They perform differently and they price differently.
Either way, resin is a wearing course, not a structure. It goes over tarmac or concrete, so a resin drive is really two jobs stacked up: build the base, then lay the finish. A resin surface over a base that moves will crack in exactly the place the base cracked.
Tarmac
Bitumen macadam, laid hot as a binder course and a surface course, rolled while it is still going off.
It goes down fast, it handles a long or awkwardly shaped drive better than block paving does, and there are no joints for weeds to get into. On a big farm entrance or a shared access it is usually the sensible answer.
The trade-off is that it is one continuous sheet. Any repair is a visible patch, and it will never quite match. It softens in real heat, so turning the steering while parked will scuff it, and diesel drips attack the bitumen rather than just staining it.
The part that decides all three
Under every one of them sits a sub-base, and that is where the money should go.
Standard MOT Type 1 is a well graded crushed stone with fines in it. Those fines are the point. They let it compact down into something dense and tight that carries load. What it will not do is drain. Water arriving at the top of a Type 1 base mostly stays there or runs off sideways.
Permeable construction works the other way round. It uses an open graded angular stone, typically 4/20mm crushed rock under BS 7533-13, with the fines taken out. That leaves roughly a third of the volume as void space, so the base doubles as a tank. Rain passes through the surface, is held in the stone, and then either soaks away into the ground or is released slowly to an outlet.
That distinction is not academic round here. The SUDS scheme at Lamb Drove in Cambourne has been monitored for years, and a Cranfield University study of the permeable paving there found it still coped with the heaviest rainfall recorded on site despite limited maintenance. It works. It only works because the base underneath was built to do it.
Depth depends on the ground and the load. A soft or clay subgrade, a van instead of a car, a slope, an existing drive that turns out to be forty years of patched hardcore - all of them push the dig deeper. Any contractor quoting a fixed excavation depth before seeing what is under your existing surface is guessing.
Planning, briefly
Since 2008, laying more than five square metres of impermeable surface in a front garden has needed planning permission, unless the water is directed to a permeable area inside your own boundary. Permeable construction, or a drive that drains to a soakaway or a border, stays within permitted development. Our guide to driveway planning permission goes through it properly, and if you need to cross the footpath to get on there, the dropped kerb guide covers that side.
What to ask before you accept a quote
- The excavation depth, and whether the spoil is being taken away or spread on site
- The sub-base material by name, and its compacted depth, not just "hardcore"
- Whether a geotextile membrane is going over the subgrade
- Where the water goes once it hits the surface
- How the edges are being restrained
A quote that answers those five is a quote you can compare against another one. A price per square metre on its own tells you nothing, because two contractors can quote the same number for a 100mm dig and a 250mm dig.
Thinking about a new drive?
We lay block paving, resin and tarmac across Newmarket, Cambridgeshire and Suffolk, and we do the groundworks ourselves rather than subbing out the part that matters. That means the dig, the drainage and the base are our problem, not something inherited from whoever came before. Call 07916 033276 or request a quote and we will come and look at the ground before we put a price on it.
More on what we do in driveways and paving.