Products approval body says it was given no reason to alter fire rating – unlike its French counterpart
Construction products approval body the BBA has defended its decision not to follow the example of its French equivalent and downgrade the fire performance of the cladding used on Grenfell Tower.
The BBA accredits the performance of construction products with its stamp of approval, widely accepted by specifiers, building control and insurers.
French certification body CSTB lowered the fire rating of Reynobond ACM cladding panels featuring a polyethylene core back in 2014.
The decision meant the rating for the polyethylene core panels, known as Reynobond PE, was taken below UK building regulations’ requirements for use on buildings over 18m high – meaning had the French ratings been used in the UK, the cladding would not have been allowed.
“We were not informed by the manufacturer of any changes to the product”
The panels were eventually withdrawn from the global market for use on tall building days after last June’s Grenfell fire in west London which killed 72 people.
But the BBA said it only revises its certificates when a manufacturer advises it of “any changes to the product formulation or specification”, adding that Arconic, the Pittsburgh-headquartered manufacturer of Reynobond, had not notified it of any changes.
It said: “We cannot comment as to whether or not the CSTB downgraded the fire rating of Reynobond. The BBA did not make changes to the reaction to fire classification of this product as we were not informed by the manufacturer of any changes to the product that could have affected the fire rating.”
Part B, the building regulation dealing with fire safety, stipulates that external cladding panels used on buildings over 18m must have a reaction to fire rating of Class 0 to British standards or a B to European standards unless satisfactory fire performance can be proven in a full-scale test.
ACM panels with a polyethylene core failed the full-scale testing carried out by the government after the Grenfell disaster.
The French certification body gave Reynobond PE a B rating in 2011 but revised this down in December 2014 to a C for a flat panel fixed using rivets and an E for a cassette type system with folded corners.
The BBA certificate for Reynobond, dating from 2008, gives the polyethylene and fire retardant variants of the product a B rating. The certificate was still current at the time of the Grenfell fire but was revised in August last year to refer only to the fire retardant version of Reynobond.
In its statement, the BBA added it was a contractual requirement for manufacturers to disclose any changes to the product formulation or specification. There is no suggestion Arconic changed the formulation of Reynobond PE.
Arconic said it had advised “various customers and certification authorities” of the changes to the classification results and that these were “also posted on the CSTB’s publicly available website”. The BBA declined to say if it had been advised by Arconic of the rating change by the French of Reynobond PE.
The issue raises questions over the transparency of the product testing process and the consistency of product certification, which is largely carried out by private companies in competition with each other.
One industry source described the product testing system as “chaotic”.