Speed bumps on public roads in the UK are governed by specific regulations that dictate their dimensions, placement, signing, and approval process. A non-compliant installation can result in enforcement action from the highway authority — or legal liability if a collision results. This 2025 guide covers the regulations in full.
Primary Legislation: The Highways (Road Humps) Regulations 1999
Speed bumps on public highways in England and Wales are governed by The Highways (Road Humps) Regulations 1999 (SI 1999/1025), made under the Road Traffic Regulation Act 1984 (sections 90A–90F).
In Scotland: Road Humps (Scotland) Regulations 1998. In Northern Ireland: Roads (Miscellaneous Provisions) Act (Northern Ireland) 2010.
What the Regulations Prescribe
Maximum Height: 100mm
Road humps must not exceed 100mm in height above the adjacent road surface. Standard speed humps are typically 75mm high. Lower profiles (25–50mm) are used for speed tables.
Minimum Length (Front-to-Back Profile)
- Approaching speed 20mph or less: minimum 900mm length
- Approaching speed 25mph: minimum 1,600mm length
- Approaching speed 30mph: minimum 2,700mm length
- Speed tables (flat-topped): minimum 3,700mm flat top length
Width
Humps must extend full road width. Speed cushions (with gaps for buses and emergency vehicles to straddle) are a permitted variant — cushion width typically 800–900mm with gaps of 800mm+ on each side.
Mandatory Signing Requirements (TSRGD 2016)
- Warning sign: Diagram 883 ("road humps") triangular warning sign before the first hump in a series
- Advance warning distance: ~75m before the first hump on 30mph roads
- Road marking: Yellow reflective transverse markings (diagram 1062.1) immediately before the hump
- Illumination: Signs must be illuminated or reflectorised per TSRGD
Consultation Requirements
Before installing on a public highway, the highway authority must consult:
- Chief officer of police for the area
- Traffic commissioner
- Bus operators with routes over the affected road
- Fire and rescue service
- Ambulance service
Minimum 28-day consultation period. Objections from emergency services can result in scheme redesign or abandonment.
Private Land: Different Rules
Speed bumps on private land are NOT subject to the Highways Regulations:
- No planning permission required in most cases
- No formal consultation required
- No prescribed dimensions
- No mandatory signing — but strongly recommended for public liability
Under the Occupier's Liability Act 1957, you have a duty of care to users of your land. Unmarked, badly positioned, or oversized speed bumps could expose you to negligence claims.
Common Mistakes
- Speed bumps on adopted roads without approval: Illegal — highway authority can require removal at your cost
- Height exceeding 100mm on public highways: Non-compliant; increases vehicle damage risk
- Insufficient length: Short, sharp humps are non-compliant and create greater vehicle/occupant risk
- Missing signing: Legally required on public highways; creates liability on private land if unmarked
- Poor fixings: Rubber bumps that work loose create significant hazard — inspect regularly
Getting Road Humps Approved: The Process
- Contact your local authority highways department with a written request
- Traffic survey: authority will want speed data showing the problem
- Scheme design by authority's engineers (or appoint a transport consultant)
- Mandatory 28-day consultation with statutory consultees and residents
- Budget allocation (you may need to fund the scheme or secure Section 106 contributions)
- Works by the authority's highways contractor
For private roads, the process is much simpler. Browse our speed bump range for supply-only or contact us for a supply-and-install quote.