The evidence given at the Grenfell Tower inquiry has become more shocking by the day, especially in relation to the behaviour of certain manufacturers.

Paul Finch

Deliberately misleading architects about the suitability of products for use in towers sounds like the basis for future prosecutions, irrespective of civil actions, which look certain to follow.

Watching proceedings on YouTube has been a dispiriting experience at best. The only comfort to be had is the growing certainty that the rotten state of the construction industry as a whole will be addressed by government once the final report on the affair is published.

This will have implications for the whole property sector – not just housebuilders – because issues related to rainscreen cladding, composite products, insurance, liability and contractual procedures apply across the board. The insurance industry is already caning architects, massively increasing professional indemnity premiums.

There is a question as to whether the official government guidance on ways of complying with fire regulations was unambiguous and correct or easily capable of misinterpretation because of poor drafting. If the former, then countless architects and others have been getting it wrong for years. Have they been negligent when all competent professionals were doing the same thing?

Grenfell Tower

Source: Shutterstock/Sasa Wick

Shocking evidence: the inquiry must trigger reform in the property sector

If they have, then the insurance sector will take a terrible hammering because rectification of faulty design and construction will result in legal actions against designers, design-and-build contractors and specialist subcontractors involved in design. Successful claims will result in insurers having to pick up bills of an unprecedented size.

But if the advice in Approved Document B Volume 2 (ADB2 in the jargon) is defective, it makes the government liable for the cost of rectification. This is a huge political issue and it may be a catalyst for the sensible policy of single-project insurance.

For design-and-build contractors, there will be some fundamental changes to contractual arrangements and practices, revealed in all their lack of glory at the inquiry. Ambiguity about who is responsible for what, changing of drawings without consultation or consideration of design and regulatory implications, changes of specification and very basic faults in construction inspection (for example, it didn’t happen) are not acceptable.

Good intentions

The client, an arm’s-length branch of Kensington and Chelsea Council, did not behave as a commercial client would have, in terms of overseeing what was being designed and delivered. But it would be a mistake to think evil Tories were intent on victimising working-class council tenants.

The council was spending £90,000 per unit on an upgrade intended to increase effective insulation and brighten the block’s grim appearance. There was nothing wrong with the intentions.

Moreover, the inquiry’s design expert witness, former RIBA president Paul Hyett of Vickery Hyett, gave convincing evidence that it would have been possible to meet Building Regulations pertaining at the time with a proposal using the same rainscreen cladding, provided the insulation behind it was mineral wool instead of polyisocyanurate. The cladding, an aluminium composite product, included a plasticised core that does not burn that easily, except when subject to extreme temperatures, and did not include a readily available fire retardant.

It burned so horribly because the design as built did not include the necessary fire stops and cavity barriers, creating a vertical chimney that generated extraordinary temperatures with horrific results. In other words, people in blocks with similar cladding may well not be living in death traps, provided basic regulations were observed in design and construction.

What happened in Grenfell was a perfect storm. The only crumb of comfort is that long-needed reform of the construction sector may finally happen. The era of risk transfer should come to an end.

Paul Finch is programme director of the World Architecture Festival