Air Rights Schemes Create New Homes


The iconic Glass House building in Bermondsey with three new floors added in lightweight construction to an existing occupied residential building. The existing warehouse that was unable to support the new floors was reinforced with elegant steel ‘legs’ .

London architects are continually searching for acceptable ways to ease the urban housing shortage – which has resulted in such high prices that key workers are being excluded from the housing market and young workers people being priced out of the City.

More land is needed to create new homes but where is it at an affordable price? Some architects such as Kemp Muir Wealleans have long been suggesting building on top of existing, often occupied, buildings. As you can see from the accompanying photographs of our completed and current ‘air rights’ projects we have been doing so for well over a decade.

Seeking the “air rights” to build over an existing structure or transport link is something commercial property developers have already become good at in London’s commercial areas but, other than the ubiquitous mansard roof additions, significant residential interventions have not been common.

England has relatively little spare land and low-rise cities such as London have a lower population density than other European cities, which tend to have four and five-storey apartment blocks.

Utilising air rights over relatively low flat roof buildings – many were built during the 1960’s and 1970’s could create numerous sites for new homes.

The economic argument is compelling. Land prices in London can be 80% of the cost of building a home and air rights homes are cheaper than comparably located conventional homes.

The key to viable development is the use of lightweight structures. Prefabricated housing modules can be half the weight of conventional houses and ideal for placing on existing structures that have spare capacity. Many of the buildings built in the 1960’s and 1070’s have spare load capacity that is sufficient to carry an extra floor. Where they don’t have sufficient capacity loads on existing foundations can be reduced by additional structure or stripping out redundant plant, equipment and floor screeds.

On one recent project, (see Albemarle House in Beckenham), we were able to reduce loads sufficiently by demolishing the top floor of an old office building to build back three new floors in lightweight construction.

On another project (the iconic Glass House in Bermondsey), we were able to add three floors by introducing new structural elements in the form of circular columns expressed as architectural features alongside the exterior walls.

Our residential architects lead the field in this form of development and if you have an air rights scheme in mind that you would like to discuss please do not hesitate to give us a call on 020 7471 8540 or email to