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Hello and welcome to the Grenfell Tower Inquiry podcast with me, Kate Lamble.

On the week of the fifth anniversary of the Grenfell Tower fire, two expert witnesses

levelled a series of criticisms at the building safety regime.

One described the competence levels among fire safety professionals as

extremely poor. We've got to the point where we really cannot assess in a credible way

who's competent and who's not. Jose Torero also called for the stay-put strategy to be abandoned.

Another fire safety expert was appalled at the misuse of fire tests by a manufacturer.

I was absolutely incredulous. I could not believe that this was going on. I simply could. I refused to believe that it was happening.

Let's get started with the evidence then. One of the expert witnesses who gave evidence this week is Luke Bisbee.

He's a professor of fire and structures at the School of Engineering in the University of Edinburgh. He's given evidence to the inquiry before several times, which you can hear in episodes 1995, 96, 172 and 198 of this podcast. This time, he was speaking about how combustible cladding and insulation got to be

installed on the 24-storey block. Building regulations in England and Wales used to set out

specific standards products had to meet, but in the 1980s, that changed to so-called functional

requirements. It meant the regulations simply said the external walls of buildings

should adequately resist the spread of fire. Designers and contractors had a number of options

for how they could comply, one of which was to follow government guidance. In his report,

Luke Bisbee said this change meant finding ways to get round the standards suggested was no longer a matter of finding loopholes.

It was the intent of the regulatory system.

Lead counsel to the inquiry, Richard Millett.

Are you saying that instead of having a prescribed system

where people would look for loopholes with which to circumvent,

you created a new open texture and flexible system where you

...