Kensington & Chelsea
If you visit the Royal Borough of Kensington and Chelsea you cannot fail to notice the extensive development of basement excavations that are in progress. Unable to extend out sideways, homeowners in the borough are choosing to extend down and out under back gardens.
The number of planning applications for basements has risen substantially year on year in recent years and in some cases these extensions are going three stories down. Needless to say, this significant increase in the number and the size of the projects has given rise to issues about noise, disturbance during the construction and the structural stability of nearby buildings.
Consequently, in early 2013 the Council issued tougher controls on applications for underground building in the Borough which amongst other things, meant that basements would be limited to no more than one story and extending under gardens to no more than half the garden size (compared to the original regulation of no more than 85% of the garden).
Further restrictions prohibit basements being constructed under listed buildings or indeed, under an existing basement. Then in late 2014, the Government endorsed the Borough’s attempts to restrict the development of multi storey basements and the council formally approved the strategy in January 2015. So now, in the Borough of Kensington and Chelsea, so called “iceberg homes” with private cinemas, swimming pools and the like underground had been seriously curtailed. So Kensington and Chelsea led the way and now a number of other boroughs such as Hammersmith & Fulham, Westminster, Islington to name just a few are adopting similar policies.
However, it should be borne in mind that these controls are not the consequence of planning authorities being anti basements. In fact, it is openly recognised that they are a very useful and effective means of extending living space, particularly where extension of the building up or sideways is not possible. But, there is still a need to ensure that proposals to extend underground do not prove to be detrimental to the environment or the surrounding neighbourhood.
The full, adopted policy for the Royal Borough of Kensington and Chelsea can be seen here: