Driveways and Parking: Surfaces, Drainage Rules and Costs

A new driveway or expanded parking area involves more regulatory considerations than most homeowners expect. The planning rules changed in 2008 to address the impact of front garden paving on urban flooding; drainage requirements now affect the choice of surface material; and a new dropped kerb on a classified road always requires highway authority consent. Getting these right from the start avoids the need to redo work or face enforcement action.

Planning Rules for Front Garden Hardstanding

Paving over a front garden is permitted development (no planning application required) provided the surface is permeable, or the drainage is directed to a lawn or border rather than the public road. Specifically:

• If the hardstanding is under 5m2, it's permitted development regardless of drainage.
• If it's over 5m2 and uses an impermeable surface (concrete, impermeable tarmac, most porcelain paving), planning permission is required unless the drainage runs to a permeable area on the property.
• If it's over 5m2 and uses a permeable surface (gravel, permeable block paving, open jointing), it's permitted development with no drainage condition.

The simplest approach for large driveways is to use a permeable surface, which keeps the project within permitted development regardless of size. Block paving with narrow open joints filled with sand, or purpose-made permeable paving systems, satisfies the requirement.

In Conservation Areas and for listed buildings, the usual stricter controls apply: planning permission may be required for any works to the front curtilage regardless of size or surface type.

Dropped Kerbs and Highway Access

Creating a new vehicle access to a property from a public road requires a dropped kerb, and the dropped kerb requires the highway authority's (usually the council's) consent. This is separate from planning permission and involves a highway inspection and, if approved, a formal construction specification. The council's own contractors typically carry out the dropped kerb work, at a cost borne by the applicant.

The consent process for a dropped kerb involves checking that the visibility at the access point is adequate (sight lines to allow a vehicle to pull safely into traffic), that the footpath width is maintained, and that no statutory services are affected by the kerb lowering. On busy or classified roads, the requirements are more stringent.

Allow 6-12 weeks for dropped kerb consent from the date of application. Don't start any driveway construction until consent is confirmed: building a driveway that then can't be accessed from the road because the kerb wasn't approved is a costly mistake.

Surface Material Comparison

Tarmac (asphalt). The most common driveway surface in the UK, particularly for longer driveways. Laid hot in multiple layers over a compacted sub-base. Durable, quick to install, and lower maintenance than most alternatives. Standard tarmac is impermeable; porous tarmac is available and satisfies permitted development drainage requirements but is more expensive. Tarmac driveways should be sealed periodically (every 3-5 years) to extend their life. Costs: £40-£80/m2.

Block paving. Concrete or clay pavers on a compacted sub-base with a sand bedding layer. Highly durable if properly installed, can be individually replaced if damaged, and looks better than tarmac for most residential applications. Permeable block paving (wider joints, open graded sub-base) is available and satisfies drainage requirements. The quality of the installation depends heavily on the sub-base: a poorly compacted base produces a surface that settles unevenly within a few years. Costs: £70-£130/m2.

Resin-bound gravel. Aggregate chips bound together with a clear polyurethane resin, applied to a rigid base (concrete or tarmac). The result is a smooth, permeable surface that looks distinctive and is very low maintenance. Popular in higher-specification applications. Susceptible to damage from stone chips (vehicles and impact) if the resin bond is insufficient. Costs: £70-£120/m2.

Loose gravel. The cheapest hard surfacing option. Permeable. Requires periodic raking and replenishment. Migrates onto the road and into borders. Uncomfortable to walk on in heels. Deters some trespassers (audible to walk on). Costs: £15-£35/m2.

Pattern imprinted concrete (stamped concrete). Concrete coloured and imprinted to resemble block paving or stone. Lower cost than genuine block paving. Cracks more readily than block paving (no movement accommodation in a monolithic slab). Once cracked, repair is difficult to make invisible. Popular but arguably the worst value for money over a 15-year horizon. Costs: £50-£90/m2.

Sub-Base: The Critical Element

All driveways must carry vehicle loading. The sub-base that the surface sits on determines whether the finished surface remains level and intact, or settles, ruts, and fails within a few years.

For most residential driveways (standard cars, occasional small vans), the minimum sub-base is 150mm compacted Type 1 MOT aggregate (crushed stone) over a geotextile membrane on prepared ground. Where soft ground conditions exist, where heavy vehicle access is anticipated, or where the ground has been disturbed recently (as after a building project), 200-250mm of Type 1 is more appropriate.

The most common cause of driveway failure is inadequate sub-base depth or inadequate compaction. Plate compactors are the required tool; hand compaction is not adequate. A driveway installer who proposes to compact by hand is telling you they're cutting corners.

Costs

A typical single-car driveway of 30m2 in block paving, with a dropped kerb, costs £3,500-£6,000 in total. A double driveway (50m2) with the same specification costs £5,000-£9,000. London and south-east prices are typically 20-30% above these ranges.