When it matters: how UK-based materials expertise underpins cable performance on site

On site, cables are often pulled through holes and routed to outlets, switches and fixtures before the walls and ceilings are finished and openings sealed - sometimes in difficult and challenging site conditions. 

For housebuilders, understanding how cables perform on site is just as important as compliance on paper. This is where Prysmian's UK-based cable manufacturing and materials expertise is critical. With its in-house polymer specialists, chemists and dedicated UK test laboratories, the cable manufacturer can respond quickly to both technical and performance questions from contractors and developers. It turns concerns raised on site into evidence‑based answers.

A recent collaboration with leading electrical contractor Clarkson Evans, working for a major housebuilder, demonstrates how this capability is beneficial. 

The alliance began with a practical question raised by Clarkson Evans following discussions with its housebuilder client: how might commonly used sealants affect the long-term integrity and performance of installed PVC-sheathed cables? 

The question was based on the reality of the site installation, where cables were being routed through masonry and timber and then the penetration sealed to ensure fire, acoustic or thermal requirements are met. There is an assumption that commonly used sealants are compatible with cable sheaths. Clarkson Evans questioned this assumption. The electrical contractor wanted to assure its client that the sealants used on this development would be compatible with its use of Prysmian cables.

Rather than relying on generic data or theoretical guidance, Prysmian’s UK technical team worked directly with Clarkson Evans to establish which sealants were being used and where on the project. This allowed it to replicate the site applications in its laboratory.

UK labs replicating real-world installation

Prysmian's materials experts then designed an ageing and compatibility test to mirror site practice. Cable samples were installed through drilled apertures in brick, block and timber elements and controlled amounts of sealant applied. The samples were suspended in air ovens at various temperatures before undergoing testing in Prysmian’s UK test facilities. In addition, samples were artificially aged to get a better idea of long-term aging effects.

Tests in accordance with British and European Standards were used to assess the cables' mechanical performance, flexibility and any change in physical properties after the heating and aging processes. Importantly, the work was carried out entirely in-house, allowing rapid testing, scrutiny of results and clear interpretation of outcomes.

For Clarkson Evans and its housebuilder client, the testing delivered exactly what was needed: clear, evidence-based guidance that the Prysmian cable products specified were compatible with the proposed sealants under typical site conditions. 

Importantly, the results highlighted that compliance alone does not tell the full story, and that understanding how different materials interact under real installation conditions provides a deeper level of assurance. 

The tests demonstrated the resilience of Prysmian cable products, reinforcing its reputation as a trusted, innovative partner to electrical contractors, housebuilders and developers. They also showed how having a UK-based technical capability enables the company to provide support across the construction sector. In addition, they highlighted Prysmian’s ability to move quickly from customer query to controlled testing, without having to rely on third-party laboratories or overseas facilities.

Supporting best practice in the construction industry 

As construction continues to evolve with increased focus on performance, safety and longevity, evidence-based decision making will become increasingly important. This project demonstrates that when compatibility questions arise on site, with potential long-term consequences, the performance of Prysmian cables can be proven rather than assumed.

For UK electrical contractors and developers, having a cable manufacturer partner with in‑house materials scientists, chemists and test facilities gives them the confidence that issues can be addressed quickly, rigorously and realistically. And, in an industry where the true test of quality often comes long after project completion, that assurance can make all the difference.