First it was mega-basements, now joined homes are coming under scrutiny.
The Royal Borough of Kensington & Chelsea (RBKC) has said it is keeping a stern eye on homeowners who want to knock properties together in attempt to meet its supply targets and prevent the loss of any more homes.
Research from high-end property search firm Huntly Hooper found that the council, home to the UK's most expensive addresses, has so far rejected nearly 45 per cent of so-called amalgamation applications this year after turning down 47 per cent in 2015.
This compares with just three per cent in the previous two years respectively, 9.5 per cent in 2012 and no refusals in 2011, the analysis of the council's planning applications shows.
Like other London boroughs, Kensington & Chelsea is under pressure to build more homes and meet targets set out by mayor Boris Johnson in his revised London plan last year.
In 2014, the council changed its policy so that anyone that wanted to combine more than two units together was required to submit plans.
Previously planning approval was only required where more than five units were being turned into one home – for example the conversion of block of flats. This would have partly explained the jump in the figures between 2013 and 2014.
A council spokesman told City A.M. “We have a stretching housing target of 733 units per annum set out in the London Plan and the loss of any units would have to be added to this figure."
“Therefore any schemes which involve the loss of housing will be closely scrutinised.”
Ollie Hooper, the founder of Huntly Hooper, said the move may further increase the value of top-end mansions in the area: "Larger dwellings currently trade at a premium in prime central London, with superprime values now more than double that of prime values (£3,099 per square foot compared with £1,522 psf)."
"And so restriction of amalgamation, plus already implemented limitations on basement creation in RBKC, may further enhance the premium for larger properties into the future. Indeed the top end of the market was the best performing sector last year," he added.