The Building Engineering Services Association (BESA) and the Thermal Insulation Contractors Association (TICA) have issued a joint statement raising concern about the suitability of pipework normally used for underground primary heating networks, now being deployed inside buildings.

They are particularly concerned about the use of coiled flexible polyethylene insulated piping systems.

In a joint statement, BESA and TICA said: “We have increasing evidence that these systems are being installed in high-risk buildings, such as large multi-residential buildings.”

They warn that a “fundamental change in product application” has taken products outside the scope of the quality standards normally applied to their performance.

Building services pipe insulation specifications typically reflect the requirements of BS 5422 to ensure full compliance with Building Regulations.

But, pre-insulated pipework systems typically use either PUR or PE insulants, which do not meet the fire performance criteria typically specified in building services applications.

Graeme Fox, BESA’s Head of Technical, said: “One of the important lessons learned from the Grenfell tragedy was that products may have been tested and certified, but not necessarily for the particular application in question.

“We would, therefore, expect all responsible supply chain firms to be able to provide details of how the Euroclass fire rating of the PUR/PE system was achieved and the arrangement of the insulants in the test to determine their exposure to heat and flame,” he added.

A one-size-fits-all approach to insulation thickness typically undertaken by manufacturers of pre-insulated pipework could also fall short of building thermal performance targets, warned Fox

“We would also expect them to be able to evidence compliance with BS 5422 heat loss/heat gain tables clearly.”

Manufacturers, distributors, and installers of pre-insulated polyethylene pipework systems are being reminded of their responsibility to provide evidence of the suitability of these products for the specific application specified.

Specifiers are also urged to check on the thermal performance of the polyethylene system and question whether it has the appropriate Euroclass fire rating

Chris Ridge, TICA’s Technical Policy Manager, said all responsible companies should be able to provide current Euroclass fire test certification for “the complete range of polyethylene pre-insulated pipework products.”

“Looking ahead, we seek to challenge the wider industry to ensure that all pre-insulated systems meet the required standards. This should not stop at pre-insulated pipework but should also include pre-insulated ductwork products,” he added.