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Grenfell: Rydon ‘reliant on others’ for suitability of façade spec

17 July 2020

Rydon, the main contractor on the refurbishment of Grenfell Tower, was “reliant on others” when it came to ensuring the suitability of materials used on the façade, the inquiry into the fire has heard.

Former Rydon contracts manager Simon Lawrence appeared before the Inquiry yesterday to give evidence.

Richard Millett QC, leading counsel to the Grenfell Tower Inquiry, asked Lawrence if Rydon had any processes in place to ensure that materials which readily supported combustion were not used on any of its building façades.

Lawrence replied: “Well, I think it would be using a competent design team, competent specialist contractors, backed up by Building Control, and all the layers within.”

Millett asked if this meant “reliance on others”, to which Lawrence replied that it did.

Asked by Millett what system Rydon had in place to ensure that the suitability of materials to be used on the façade were judged in relation to their conditions of use, Lawrence replied: “We would be reliant on others. We would be reliant on the design team.”

Millett also referred to Studio E architect Bruce Sounes’s witness statement in which he said that the specialist cladding subcontractor would hold responsibility for all aspects of their system and the successful contractor had the discretion to suggest alternative products or materials.

Lawrence agreed that Rydon had the discretion to change manufacturers with the acceptance of the client.

Asked if Rydon did investigate changing manufacturers or products or materials, Lawrence replied: “I think we – at tender stage we offered alternatives as we were asked to do, but I think there was another manufacturer of ACM cladding.”

He also confirmed that “contractually” it would be Rydon who was ultimately responsible for suggesting alternative materials and products but that “in practice, the knowledge would come via the specialist subcontractors”.

CWCT document not on site

Meanwhile, Millett probed Lawrence on the NBS specification document for Grenfell Tower, produced by architect Studio E. The document stipulated that copies of the CWCT “Standard for systemised building envelopes” as well as “publications invoked by CWCT’s Standard for systemised building envelopes” should be kept available at the design office, workshop and on site “for the duration of the contract”.

Lawrence admitted that he did not note this paragraph after Rydon won the tender and had not used the CWCT documents before. He also confirmed that a copy would not have been kept on site. Asked why not, Lawrence replied “It obviously wasn’t picked up in all the documents we had to go through and comply. It obviously wasn’t noticed.”

Asked by Millett why it wasn’t noticed, Lawrence replied: “Just the sheer amount of information, I would suggest.”

Millett read out two paragraphs from the CWCT standard, which read: “The building envelope shall not be composed of materials which readily support combustion, add significantly to the fire load, and/or give off toxic fumes.

“In all cases , products or elements of construction requiring a fire resistance or spread of flame performance should have the appropriate evidence of performance based on test information. The final installation should follow the applicable test evidence in all respects.”

Lawrence responded that although he had not seen the document, he was familiar with the principles expressed within it that a building envelope shouldn’t be composed of materials which support combustion, add to the fire load, and/or give off toxic fumes.

Fire barriers

Millett also asked Lawrence about whether or not Rydon had processes in place to ensure the need for effective fire barriers was considered properly on Grenfell. Lawrence replied that Rydon did so by appointing the specialist subcontractor Harley Curtain Wall, as well as the design team Studio E and Curtins.

Millett went on to ask if Rydon had any processes in place for ensuring that the external insulation system for walls of multi-storey buildings wasn’t a fire risk after completion.

Lawrence replied: “Yes, because we had employed specialist designers that should have been designing and installing to the regs. It was then checked not only by an independent clerk of works but it was also checked by the Building Control officer.”

Millett said: “So not wishing to summarise your evidence unfairly, but reliance on others?”

Lawrence replied: “Yes.”

The Inquiry continues.