Grenfell Tower underwent a major renovation, announced in 2012 and conducted over 2015–16.
The tower received new windows, a water-based heating system for individual flats and new aluminium composite rainscreen cladding.
According to the application, the purpose of the cladding was to improve heating and energy efficiency, and external appearance.
Mark Harris, of Harley Facades, said, "from a selfish point of view", his company's preference was to use (cheaper) aluminium composite material.

Two types of cladding were used: Arconic's Reynobond PE, which consists of two coil-coated aluminium sheets that are fusion bonded to both sides of a polyethylene core; and Reynolux aluminium sheets.
Beneath these, and fixed to the outside of the walls of the flats, was Celotex RS5000 PIR thermal insulation.
An alternative cladding with better fire resistance was refused due to cost.

The original contractor, Leadbitter, had been dropped by KCTMO because their price of £11.278 million was £1.6 million higher than the proposed budget.
The contract was put out to competitive tender and won by Rydon Ltd, whose bid was £2.5 million less than Leadbitter's.
Rydon carried out the refurbishment for £8.7 million, with Artelia on contract administration and Max Fordham as specialist mechanical and electrical consultants.
The cladding was fitted by Harley Facades of Crowborough, East Sussex, at a cost of £2.6 million.
Grenfell Tower underwent a major renovation, announced in 2012 and conducted over 2015–16. The tower received new windows, a water-based heating system for individual flats and new aluminium composite rainscreen cladding. According to the application, the purpose of the cladding was to improve heating and energy efficiency, and external appearance. Mark Harris, of Harley Facades, said, "from a selfish point of view", his company's preference was to use (cheaper) aluminium composite material.
Two types of cladding were used: Arconic's Reynobond PE, which consists of two coil-coated aluminium sheets that are fusion bonded to both sides of a polyethylene core; and Reynolux aluminium sheets. Beneath these, and fixed to the outside of the walls of the flats, was Celotex RS5000 PIR thermal insulation. An alternative cladding with better fire resistance was refused due to cost.
The original contractor, Leadbitter, had been dropped by KCTMO because their price of £11.278 million was £1.6 million higher than the proposed budget. The contract was put out to competitive tender and won by Rydon Ltd, whose bid was £2.5 million less than Leadbitter's. Rydon carried out the refurbishment for £8.7 million, with Artelia on contract administration and Max Fordham as specialist mechanical and electrical consultants. The cladding was fitted by Harley Facades of Crowborough, East Sussex, at a cost of £2.6 million.
Grenfell Tower fire