Driveway Drainage Guide — Choosing Driveway Channel Drains

Why does a driveway need drainage?

Impermeable driveway surfaces — block paving, tarmac, concrete — do not allow rainwater to soak into the ground. Without drainage, surface water runs off the driveway onto the public highway or into neighbouring properties. Most planning and building regulations require new driveways to manage surface water on site or to a drainage system.

Where should a driveway channel be positioned?

The most common position for a driveway channel is at the base of the driveway slope — typically at the junction between the driveway and the public pavement, or just inside the property boundary. This intercepts surface water before it reaches the public highway.

Channels are also installed across the driveway at the point where the slope changes direction, or at the garage threshold to prevent water entering the garage floor.

What load class do I need for a driveway channel?

B125 is the documented load classification under EN 1433 commonly considered for residential driveways where cars and light vehicles will cross the channel. B125 is a minimum requirement — not a universal guarantee. Final suitability depends on traffic type, crossing frequency, installation position and the manufacturer's technical requirements. An A15 channel must not be used in a position where vehicles will cross it.

Polymer concrete vs polypropylene for driveways

Both materials are available in B125. Polymer concrete is heavier and generally more robust — typically used where strength and durability are the primary requirements. Polypropylene is lighter and easier to handle — often preferred for straightforward domestic driveway installations. Forti Nova supplies both types in the driveway channel range.