Drainage for tarmac drives in Devon

How much does tarmac driveway drainage cost in Devon?

Rates in Devon follow the South West, about 3% above our UK midpoint.

Item	Guide price (inc VAT)
Linear drainage channel	£62–£124 per metre
Soakaway or crate unit	£670–£2,050 each

Towns we cover in Devon

Postcode areas: EX, PL, TQ.

What is included?

Driveway drainage is the plan for where rainwater goes once it hits a sealed tarmac surface: the falls that move it, the channels or gullies that catch it, and the soakaway, border or approved drain that takes it away.

Falls set across the drive, typically 1 in 60 to 1 in 80
Linear channel at garages, doors or the bottom of a slope
Soakaway or crate unit sized to the area and ground
Runoff directed to borders or a permeable strip
Connection to an existing surface-water drain where allowed
No connection to the foul sewer

Rules in Devon

In England, householder permitted development (Class F of the 2015 General Permitted Development Order) lets you lay a hard surface in front of a house without planning permission if it is porous, or if the rainwater is directed to a permeable area within the property. If the area is more than 5 m² and neither applies, you need permission. Standard dense tarmac is not porous, so a dense tarmac drive needs a lawn, border, channel to a soakaway or other permeable route for its water. Any new or widened crossing over the pavement needs approval from the highway authority (the county or unitary council).

How it is built