Choosing the right load class for a manhole cover
From footpaths to container yards: how the EN 124 classes map to where a manhole sits, and why the frame matters as much as the cover.
A manhole is only as strong as its weakest layer. The precast rings and cone can carry enormous loads, but the cover and frame are what wheels actually touch, so the load class has to match the traffic above.
The six classes in brief
- A15 — pedestrian and cycle areas only
- B125 — footways, pedestrian zones and car parks for cars
- C250 — kerbside channels and road shoulders, within 0.5 m of the carriageway
- D400 — carriageways of roads, including hard shoulders
- E600 — loading yards and docks with heavy forklift traffic
- F900 — airports and other areas with exceptional wheel loads
When a site sits on the boundary between two classes, specify the higher one. The cost difference is small next to replacing a cracked cover under live traffic.
Don't forget the seating
The frame must sit on a level, fully bedded adjustment ring. Point loads from an uneven seat are the most common reason good covers fail early. Our precast cones are cast with a flat, true top face so the frame beds evenly.
Specify the class for the traffic you will have in twenty years, not the traffic you have today.
