Image: Dreamstime/Alex Danila
The main concern among contractors involved in the refurbishment of Grenfell Tower was “cost and delay, as opposed to fire safety”, the Grenfell Tower Inquiry has heard.
The inquiry continued to hear evidence yesterday from Studio E architect Neil Crawford, who was asked by Richard Millett QC, leading counsel to the Grenfell Tower Inquiry, about a 2015 email exchange following a discussion about upgrading cavity barriers to withstand fire for 120 minutes.
On 26 March, supplier Siderise sent an email to Harley pointing out that under Approved Document B of the Building Regulations, only 30 minutes of fire integrity and 15 minutes insulation was required from a cavity fire barrier in reference to rainscreen cladding applications where the cavity barrier is deemed to be on the outside of the building.
Siderise added that its RH25-90/30 product would offer 90 minutes of fire integrity and 30 minutes of fire insulation and “therefore exceeds the minimum requirements”. It went on: “120-minute fire rating is generally the industry standard for curtain wall to concrete slab edge firestopping, where the firestop is located on the inside of a building and considered to be a continuation of the floor slab”.
Ben Bailey at Harley Facades then emailed contracts manager Simon Lawrence and Simon O’Connor at main contractor Rydon to note: “There is quite a large cost difference between what Siderise and the spec recommend, and upgrading to the 120min barriers we discussed on Tuesday.”
Cost increase
Lawrence wrote in an email to Crawford: “Harley via their supply chain are questioning the rating of the cladding firebreaks. Apparently by going to two hours as we discussed has a cost increase of around £12k. Their supplier is saying it only needs to be 30 minutes everywhere.”
Crawford then wrote to Lawrence and said: “Have spoken with John [Hoban, a building control officer with the local council] and he wasn’t happy with Harley’s email as we are talking about firestopping as opposed to cavity barriers. I have explained again the specifics of our scenario and he will have a conversation…to see if there is a reduced spec they can agree to and will then speak with Harley’s directly”.
During yesterday’s hearing, Millett asked, having shown Crawford the email exchange: “Do you accept that the long and the short of this email exchange is that if you were talking about cavity barriers as opposed to firestops, then 120 minutes was not necessary and that the upgrade to 120 minutes for cavity barriers would be to increase cost and possibly delay?”
Crawford answered: “Absolutely.”
Millett then asked: “Do you agree that there was some pressure on site, so far as you could understand, to avoid having to specify cavity barriers with a resistance of 120 minutes?”
Crawford again agreed.
Millett followed up by asking: “And the main concern was cost and delay as opposed to fire safety.”
Crawford responded: “Well, I can’t speak on behalf of the other participants in that conversation but you might read that into what they had written, yes.”
The inquiry continues.
