Regional Building Control (RBC) have been appointed as the Approved Inspectors for the recladding of Northumberland House in Sutton, this project is actually labelled as ‘cladding rectification works’.
The building was originally known as Sutherland House but was retitled Northumberland House after it was completely refurbished, which included the installation of a new external cladding system to provide additional thermal insulation. The building is residential with 128 flats, including car parking, it has 11 storeys and until the complete refurbishment it is understood that it was unoccupied for about five years.
Following the Grenfell fire disaster in Kensington, Northumberland House was one of the many buildings that had the cladding checked and on this building it was found to be non-compliant with the Building Regulations.
Approved Document B (Fire safety) of the Building Regulations suggests that where a building has a storey 18m or more above ground level then any insulation material used in the external wall construction should be of limited combustibility and have a surface spread of flame rating of Class ‘O’. The cladding system used on the Northumberland house refurbishment scheme was found to be not of limited combustibility and the building has a storey above 18m.
Because of this non-compliance, the complete external cladding system had to be removed and replaced with a system that fully complied with the Building Regulations and it is understood that this was carried out at an approximate cost of £900,000.
RBC are carrying out the full building control function for the recladding project on Northumberland House and the flats are fully occupied while this work is being carried out even though the building is completely surrounded with scaffolding.
The building control function is not only to check that the new cladding materials and system fully complies with the Building Regulations but also to make sure that cavity barriers are properly inserted at all relevant locations, such as the junctions of party walls and floors. This is also a requirement of the Building Regulations. Each floor is a compartment floor and each separating wall between flats is a compartment wall and the point of the cavity closers is to stop fire spreading from one flat to another flat via the cavity. Work is due to be completed shortly.
Tony Edwards, Techical Standards Manager