The Road Surface Treatments Association (RSTA) has called on local highway authorities to build 'more flexibility into the work permits they issue to surface dressing contractors' to help installation within the optimum temperature range during this summer's exceptionally hot weather.

The trade body suggested this could include allowing contractors to start work earlier in the day, to avoid the hottest midday temperatures.

In a press statement, the RSTA added: 'Surface dressing performs best when applied within a specific temperature window; installing it in excessive heat can affect how well it bonds and performs over the long-term. With the UK having already experienced three heatwaves this summer, and air temperatures reaching the mid-thirties... local authorities should avoid requiring contractors to work in the middle of the day, when road surface temperatures are at their highest.

'In direct sunlight, road surfaces absorb solar radiation and can reach temperatures far higher than the surrounding air – understood to have exceeded 50°C during the recent 35°C heatwave. This matters because there are maximum surface temperatures at which surface dressing should be installed, as set out in the TRL Road Note 39 Design Guide for Road Surface Dressing, and current conditions are pushing well beyond them.'

Mike Hansford, chief executive of the RSTA, added: 'We ask that permitting authorities allow flexibility in the timing specified in permits, to help avoid the hottest road surface temperatures. Climate scientists are predicting future hotter summers, which means climate adaptation is increasingly important, and we encourage local highway authorities to discuss with their contractor a collaborative approach to being better prepared for summer dusting of roads, making use of local authority gritting resources where available.'

Data collected by the Road Emulsion Association (REA) on this year's surface dressing season so far shows a 6% reduction in the preventative maintenance treatment compared to the same period last year. REA insiders told Highways the extreme heat is thought to be 'a contributing factor'.

A surface dressing season typically runs between April and September but is reliant on optimum weather conditions and efficient programme planning.

RSMA recommends that where binder bleeding does occur, the issue is managed by spreading a hardstone aggregate, such as granite dust (0-4mm), across the affected area. This reduces material pick-up from vehicle tyres, which would otherwise cause further damage if left untreated.

Dusting of roads involves only minimal, short-term exposure to granite dust. Guidance from the Health and Safety Executive indicates that the risk of exposure increases with heavy and prolonged exposure.

Surface dressing is the most widely used preventative maintenance treatment and seals the existing road surface from water ingress whilst also retexturing the surface which improves the skid resistance of the road.

REA consultant and secretary Kevin Maw said: 'In recent years, the April to June period has been the busiest quarter for the surface dressing season, so there would need to be a significant upturn in the second half of the year to prevent a year-on-year fall in the amount of surface dressing used in 2026.

'Every mile of surface dressing that is delayed or missed this year is a mile of road that will cost more to repair later. Preventative treatments like this remain the most cost-effective way to keep our roads in good condition, and with record funding now available, we would encourage local authorities to prioritise it before conditions deteriorate further.'