Drainage for tarmac drives in Gwent

How much does tarmac driveway drainage cost in Gwent?

Rates in Gwent follow Wales, about 5% below our UK midpoint.

Item	Guide price (inc VAT)
Linear drainage channel	£57–£114 per metre
Soakaway or crate unit	£620–£1,900 each

Towns we cover in Gwent

Postcode areas: CF, GL, NP.

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 Gwent

In Wales, a new hard surface in front of a house is permitted development only if it is porous or drains to a permeable area within the property; repairing or replacing up to 5 m² of existing hardstanding is allowed without meeting that condition. Separately, since January 2019, construction covering 100 m² or more that affects drainage generally needs approval from the council's SuDS Approving Body (SAB) before work starts, even where planning permission is not needed. Larger drives, shared surfaces and car parks often reach that threshold. Any new or widened crossing over the pavement needs approval from the council as highway authority.

How it is built