Speed control humps
Vertical speed control measures should only be used where it has been agreed that vehicle speeds cannot be controlled through the site layout. (See Passenger Transport for further details).
On bus routes speed control humps must comply with the LHDG Passenger transport guidance in Highway Layouts and Design.
Other than on bus routes, speed control humps must be flat topped humps or junction tables with a minimum plateau length of 7m and height of 75mm. Approach ramps should normally have a gradient of 1 in 13. Where the carriageway has a longitudinal gradient approaching the maximum allowed then the “uphill” ramp gradient should be 1 in 15 and the “downhill” ramp gradient should be 1 in 13.
The humps and tables must be constructed in bituminous material (unless used on a block-paved carriageway or shared surface where they should be constructed in the same material as the carriageway), using 55%/10mm medium temperature asphalt to British Standard EN 13108-4:2006 Bituminous mixtures unless otherwise agreed.
The council requires the payment of commuted sums to cover the future maintenance of speed control humps and similar vertical traffic calming measures.
Speed control bends
An overrun area must be provided to the inside of speed-control bends (a bend with an inside radius of 8m or less). It should normally be constructed as follows.
- The outer kerbline should be formed using 125mm x 150mm bull-nosed kerbs with 12mm to 15mm upstand.
- The inner kerbline should be formed using 8m radius 125mm x 225mm half-batter kerbs.
- It should be surfaced using granite setts where the carriageway is block paved or standard block paving where tarmac is used. The colour must contrast with the main carriageway.
- Setts are to be laid with a 6mm level difference between rows to form a rumble area.
- Setts are to be laid with Class 2 cement mortar bed to Series 2400 Clause 2404 of the MCHW minimum thickness 15mm, on a 150mm thick C15P concrete bed with full depth road construction below.
- It should have a crossfall of 1 in 30 towards the other kerbline.

Figure 52: Construction of overrun areas
Entry Ramps
An upward sloping ramp used at road junctions. Located at the start of the side road, the ramp controls the speed of a vehicle that has turned from the main road into the side road.
Entry ramps should normally have a gradient of 1 in 13 and a height between 75mm and 100mm.
