Linear Channel Drain (Supply & Install) – cost per m – UK 2026 Rate Guide

Budget rate for supply & lay · typical budget rate before your adjustments

Labour, plant, materials, outputs and waste — yours to edit, as an Excel. Three free.

Rates are UK national (non-London): central London and constrained urban sites typically run dearer — adjust the labour, plant and access lines in the build-up accordingly.

Linear channel drain

per m² · supply & lay

£116 – £236 / m

What is it

The supply and installation of a linear (slot / “ACO-type”) channel drain — a ~100 mm internal-width, Class D400 (trafficked, 40 t) channel supplied complete with its ductile-iron slotted grating, set to falls in a concrete surround and priced per linear metre. A linear channel drain is the surface-water interceptor a civils BoQ measures separately as “gullies & channels”. The rate carries the whole operation:

Excavated & bedded — a shallow channel trench is machine-dug and a C20/25 concrete bed laid.
Set & surrounded — the channel units are set to line & falls, concrete-haunched & surrounded both sides, and the D400 ductile gratings fitted & locked.
Backfilled — backfilled & compacted to the channel edge, ready to receive the surrounding surfacing.

Rate range

Low£116 – £149 / m

Typical£140 – £180 / m

High£183 – £236 / m

Budget rate per m².

3 key cost drivers

Channel width & loading class

A wider 150 or 200 mm D400 channel needs more material and lays fewer metres a day than the ~100 mm default; a lighter Class C250 (footway) or B125 (pedestrian) channel is cheaper. Width and load class are the biggest drivers of the per-m rate.

Grating material & class

A heavy ductile-iron D400 slotted grating (the priced default) suits trafficked yards, access roads and loading bays; a galvanised-steel-edged or lighter C250/B125 grating is cheaper for footways and pedestrian areas. Trafficked D400 also needs the full concrete surround. Described drivers, priced by swapping the channel-and-grating unit.

Location

London and the South East typically add around 20% to labour.

Estimator

Budget rate generator

£140 – £180 / m

Covers the shallow channel trench, C20/25 bed & surround, the D400 channel & grating, backfill and O&P · excl. the connecting outlet run, catchpit, disposal of arisings, kerb & VAT

Exclusions

Lifting & material distribution — telehandler / forklift, hoist and site-distribution labour (an attendance, in main-contractor prelims)
The connecting outlet run to the manhole/soakaway, any catchpit/silt-bucket unit, disposal of surplus arisings
The surrounding kerb, and any carriageway/pavement surfacing or reinstatement above the channel
Scaffold supply (usually in preliminaries)
Preliminaries — main-contractor site set-up, management & welfare
VAT