One of the most common causes of defects in roads and footpaths is the installation or repair of utilities. Although there are detailed specifications for how reinstatements should be done properly, local authorities still find themselves responsible for repairing uneven patches, cracks and potholes that have appeared after utility work has been done.

Over the past 18 months, Thermal Road Repairs (TRR) has seen an increase in demand from local authorities looking to even out the lumps and bumps in their road surfaces due to trench reinstatements. This has been a particular focus in areas which are pushing the active transport agenda; bikes, scooters and even walkers don’t mix well with ridges and uneven surfaces. Aside from the risk and impacts of human injury there is also the risk of compensation claims.

The challenge is that utility companies can only be held responsible for any defects that arise within two years of the work being done. Depending on factors such as traffic loading on the road and weather, poorly or incorrectly executed reinstatements may only rear their ugly heads after that period has passed. At which point, councils must dip into their own highways maintenance pots to put things right.

When the code of practice government street works, the Specification for the Reinstatement of Openings in Highways (SROH) was last updated, there were calls to increase the two-year guarantee period to five years. However, with opposition to that idea from utility companies, that proposed change did not make it through into the fourth version of the SROH which took over from the previous edition in May this year.

There are several things that can go wrong when contractors are reinstating roads, having excavated trenches. These include using the wrong material, incorrect compaction in either the base course or wearing course leading to voids, deterioration of the surfacing material and problems with joints. Overbanding – the process which aims to seal the joint between old and new asphalt – often doesn’t meet the specification due to poor workmanship or materials.

Our thermal process, most often deployed in pothole repair, can also be used to tackle some of the defects caused by trench reinstatement. By heating up the material either side of a joint, and then recompacting with a roller, that joint effectively disappears, becoming one homogeneous area of material.

Our larger heating units, which are 2m by 1m, are sometimes deployed to heat up material over the entire width of a footpath. Once warmed and flexible, it can be agitated, extra material added if required and then compacted. This removes voids throughout the upper layer of the reinstatement preventing the surface from sinking where the trench has been.

Although demand for this use of our technology has ramped up recently, we first used it for trench reinstatement repair some six years ago. We worked with Electricity North West to eliminate problem defects along a 6-mile trench between Preston and Chorley – and won an environmental award for doing so. You can read about that project here.


Thermal Road Repairs is a green technology company which supplies systems to improve the quality, cost and time efficiency of road repairs and paving – at a far lower environmental cost than traditional methods. We invest significantly in R&D, to create new technologies and to continuously improve our existing ones.

High output. Low emission. Permanent solution.

www.thermalroadrepairs.com