A former member of Celotex's technical team has admitted the Hadleigh-based company deliberately published misleading information about flammable material used on Grenfell Tower.

In June, 2017, the 24-storey tower was engulfed in flames with 72 people losing their lives with highly flammable cladding a factor.

Jamie Hayes, who was a technical services officer at Celotex in Lady Lane, told a lawyer at the inquiry this afternoon he knew those words used in the specification guide had been added to an email he had sent describing the product were not accurate.

Mr Hayes wrote in an email that 'Celotex RS50000 is uniquely positioned to help meet these goals. Celotex RS5000 is a premium PR solution...' However, in marketing brochure someone else pithing Celotx added: '...for use in rain screen cladding applications and suitable for use in buildings above 18metres in height.'.

Lawyer Mr Richard Millett QC asked Mr Hayes: "Those words on the page are thoroughly misleading, aren't they? They suggest RS5000 can be used on any buildings above 1800 metres, regardless of whether the construction of the cladding system on such building were the same of those of which had passed the test?"

Mr Hayes said: "Yes I would agree with that."

Mr Millet asked: "Did the fact that that they were thoroughly misleading words occur to you at the time?

Mr Hayes said: "Yes, I think they would have done"

Mr Millets said: "You knew Celotex was marketing RS500 through a thoroughly misleading statement."

Mr Hayes answered: "Yes."

The inquiry had previously heard a "pressure to increase profits" motivated the insulation company to fast-track a manipulated test of the flammable product used on Grenfell Tower.

Staff at Celotex were being pushed to sell more new products after the company was taken over by French firm Saint Gobain in 2012, a former employee said.

Mr Hayes told lawyers the acquisition "brought about a change in culture" within the company including an "increased financial pressure to develop new products" and "a sense of pressure to increase profits".

The questioning of Celotex employees in recent days has been focussed on the manipulation of a key fire safety test to secure a pass for its combustible RS5000 product for use on high-rise buildings.

RS5000 was used as the insulation in the cladding system that fuelled the spread of the fire that claimed 72 lives in 2017.

When asked how financial pressures manifested themselves in the business, Mr Hayes explained to Thursday's hearing that a second high-rise fire test was arranged "incredibly quickly" after a first one failed only a few months previously.

He told the inquiry: "Although it didn't seem that strange to me at the time I look back on that now and think it's unbelievable that only a few months passed between the failure of a major test and how quickly the second test was arranged, authorised, paid for and not to mention the fact that you would have to actually arrange to build a rig – which is to say have all the materials and have someone construct it.

"How quickly they turned around from one to two I think illustrates quite well that they were not prepared to wait any longer than was humanly possible to progress that project, and I guess the ultimate point of that project was to have a product that could be sold to increase profits."

Methods to beat the second test in 2014 included falsifying technical drawings and failing to declare that a fire-resistant magnesium oxide material had been included in the test.

Lawyers on Thursday heard that using the magnesium oxide was Mr Hayes's idea but he says he was not involved in the decision to not publicise it.

A marketing manager has been questioned over claims a Suffolk firm produced "misleading" materials about flammable insulation used on Grenfell Tower.