‘Rail overbuild schemes could create space for new homes in London’

Building homes above railway tracks is a cost effective way of tackling London’s housing shortage, according to John Parker, a director at consultant WSP. Speaking at Rail Stations and Property, Parker said that building on reinforced concrete boxes that straddle rail tracks could provide a quarter of a million homes in the capital.

This is based on WSP’s calculation that towers could be built on 10% of the capital’s 11,000km of railway, which, on average, has a 20m-wide corridor of land. “As a conservative estimate, we think that 10% of the land would be usable, taking into account bridges and tunnels and possible problems with access and neighbours, ” said Parker. “If we build 12-storey towers on that 10% to provide 100m_² apartments, that would provide 250,000 homes, which is 20 times Network Rail’s target.”

There are several benefits to building over rail tracks, the most obvious being that it requires no new land, said Parker. “It would also result in pedestrian-friendly, less car-dependent environments as there are no roads.” Railways would benefit through increased patronage while rail asset owners would see land values rise, Parker said. 

Rail overbuild schemes would generate household and business rates, as well as other revenue for the local authority. They would also support efforts by councils for higher densification in new housing developments. 

The costs of an overbuild can be high depending on span and width needed as well as the location, Parker pointed out. “A lot of that 11,000km of track is not such high value and it may be possible to do something a bit simpler that doesn’t cost so much,” Parker told delegates at Rail Stations and Property, organised by Landor LINKS and sponsored by law firm Burges Salmon.

Rail overbuild projects are already underway in the UK, including at Royal Mint Gardens Docklands Light Railway station and at Twickenham rail station. There are also plans to build a 50-storey residential block over rail tracks at Principal Place, Shoreditch, near Liverpool Street station.

Steps might be needed to reduce noise and vibration inside buildings, conceded Parker. Possible measures include tuning the thickness and span of floorplates as well as the use spring and elastomeric bearings.