New homes could be built in London using rooftop development space which would not alter the skyline and provide much needed affordable housing, according to new research.
Up to 41,000 new homes could be constructed in central London, creating 28 million square feet of residential space with a potential value of £51 billion, the research from global property consultancy Knight Frank says.
The study used the latest geospatial mapping software to identify areas where buildings can be extended upwards by using the ‘airspace’ above them. This created a Skyward method to systematically analyse the potential of each building.
Skyward analysed 3D spatial data from the Ordnance Survey, cross referencing Land Registry data to assess ownerships and Historic England data to filter out listed buildings.
It found that some 23,000 buildings could be suitable for rooftop development in London’s Zones 1 and 2, and the volume of the unused plots across the same area is equivalent to eight 800 plus meter towers without the corresponding impact on London’s skyline.
‘Skyward is a fantastically powerful tool for identifying development opportunities to unlock thousands of new homes in London and ease housing supply pressures, particularly in those areas where availability of land is becoming increasingly rare. It also has the potential to add an objective approach to planning decisions on a semi-permissive basis,’ said Charles Dugdale, residential development partner at Knight Frank.
According to Ian McGuinness, head of geospatial at Knight Frank, using 3D mapping technology the findings of this analysis can be related to other geographies easily, including to client land ownership portfolios. ‘We can now say where the opportunities are, how much value they unlock, and which land owners are best placed to drive this transformation,’ he explained.
The mapping product initially defines each contiguous block by its maximum height, then excludes unsuitable buildings such as listed buildings and those where historic airspace rights are recorded by the Land Registry, before extruding all remaining buildings up to the maximum height. Only those that can be extended by a minimum of three metres are deemed to be potential Skyward developments.