Weight load classes for channel drainage, storm drains and gully grates

When choosing a channel drain, highways cover, storm drain or gully grate for any application it’s wise to pay close attention to the weight load classes of these products. The specification of a class means that a product has been tested to be able to safely hold up to the relating weight. For example any storm drain access cover classified as D400 means it can hold up to 40 tonnes of weight before it will break and not perform properly. This universally applied across the UK thanks to the British and European Standard BS EN 124:2015 which details the below classifications.

Class  Max. weight load (tonnes)  Uses
 A15 1.5 Very light duty for pedestrian areas like gardens, patios and driveways
B125 12.5 Domestic driveway thresholds for family cars, vans and 4x4s
C250  25 Lightly trafficked roads and small private car parks
D400  40 Main roads, highways and high traffic areas like public car parks
E600  60 Industrial estates, loading bays and cargo handling yards
F900 90 Docks and airports, extreme heavy duty applications


When deciding which of the weight load classes is best for your application it’s better to err on the side of caution. If your installing storm drain access covers in a private car park that will be seeing medium-sized delivery lorries traffic them, it’s best to go with a D400 load class as opposed to a C250 to ensure public safety.

Please note: Galvanised steel manhole covers fall onto a different classification scale from 2.5 tonnes to 38 tonnes. This complete classification can be found here.