Mr Barwell (above) would later go on to become Theresa May’s chief of staff – a position he retains to this day as she prepares to leave office, putting him in a position of political authority as the response to Grenfell has played out.

The group first contacted him on 12 September 2016, inviting him to lunch and sending a copy of the correspondence with Mr Wharton.

It noted that the post-Lakanal review was promised “shortly” in November 2015 but had still not taken place. “Regrettably, we have yet to receive any announcement on this, which is of such importance to the fire and construction sector,” the letter read. It also referred to fire that caused the death of the pregnant woman in Essex – which was in Mr Amess’ constituency.

Mr Barwell did not reply. He was sent another letter requesting a response on 17 October. Again, it was ignored.

The group persisted with a letter on 7 November, pointing out that Mr Barwell had now made a statement in the House of Commons saying the government had “publicly committed ourselves to a reviewing Part B of the building regulations”. It asked for a meeting to discuss this planned review.

The APPG finally received a reply a week later, in which Mr Barwell said that the original letter never arrived. He refused the offer of a meeting as “you had a similar meeting with my predecessor” and brushed off their concerns about the ongoing delay to the review of building regulations, saying “our intention is to make a statement in due course”.

The group replied on 22 November, referring to “the frustration which the fire and construction sector has over this matter”. Once more, it did not receive a reply.

In early 2017, the MPs decided to go over his head. In two lengthy letters to chancellor Philip Hammond in January and February, they warned that the regulations had not been reviewed for a decade and warned that “there is uncertainty as to whether a [post-Lakanal] review of building regulations is even going ahead”.

The chancellor replied, thanking the group for “bringing this issue to my attention”, but told them to keep “engaging with the lead departments” – in this case, the DCLG and Mr Barwell.

“It is now over 11 years since part B was last reviewed, and I trust that the matters... will now receive your due consideration. The group firmly believes that it is now time to get on with the promised review” – APPG

But Mr Barwell was still proving difficult to contact. The APPG wrote to him again in February, seeking a response to its letter from November requesting an update on the start of the review, and saying it was “extremely concerned” that the residents’ association from the block in Southend had not received a response.

Mr Barwell replied on 5 April, finally agreeing to meet the group – some seven months on from their first letter. He accepted that it was “clearly unacceptable” that two previous letters had been “lost in transit”.

The group responded on 18 April. By now, they were so frustrated with the minister’s failure to respond that they had resolved to contact him by recorded delivery. Since the previous letter, there had been a fire in a care home with no sprinklers, which killed three residents.

“It is now over 11 years since part B was last reviewed, and I trust that the matters... will now receive your due consideration,” the group wrote. “The group firmly believes that it is now time to get on with the promised review.”

More letters were exchanged without Mr Barwell making any commitments for a review. He did finally address the fire in Southend on 2 May, brushing off concern by saying: “Each flat is designed to prevent fire spreading to adjacent flats… experience of this approach to fire safety over many years has showed this to be an effective strategy.”

But this ignored the six deaths at Lakanal and the warning from the coroner that action was necessary to prevent it happening again.

Perhaps the group would have been able to explain this to Mr Barwell at their meeting. But now it was too late. After the group’s last letter on 19 May, once again calling on him to write to the Southend residents, prime minister Theresa May called a snap election and the meeting was cancelled. Mr Barwell would go on to lose his seat.

A week later, a fridge would catch fire in west London. The fire it started would ignite cladding that had been attached to the building in the years that ministers had been prevaricating. It had a Class 0 rating.

As the flames spread, no sprinklers were present to stop the spread of the flames as they tore around the tower. The lives of 72 Londoners were avoidably lost.

But this is not the end of the story about the missed warnings from Lakanal. A further document obtained by Inside Housing proves that they were heard and ignored by the very body responsible for the management of Grenfell itself.