Europe’s deadliest building disaster in decades happened to a renovated council tower block. One possible result of last June’s Grenfell Tower fire, as towers all over Britain are inspected for safety, may be that dozens will be demolished. This suits the aims of covetous property developers and cash-strapped councils, who have long itched to get rid of these towers, often sitting on lucrative inner-city land. But is there an alternative?

To answer this we need to look at what refurbishing a tower block entails. Simple — if still expensive — things include the replacement of lifts, the upgrading of water, gas and electricity supplies, and refurbishment of common areas. More difficult are intrusive structural repairs, which can mean the building has to be emptied, providing another opportunity to unscrupulously replace the residents — as has just happened at the listed Balfron Tower in east London. Perhaps most significantly, post-war buildings had a decidedly pre-oil crisis relationship to energy consumption and conservation, and improving their thermal efficiency is in many cases not easy. Multiply all these issues by the sheer number of buildings involved and you have a major logistical and political problem.

The results of trying to achieve these works in the context of austerity, confused regulation, ruthless lowest-bidder outsourcing, and political indifference to poor communities came to a tragic head at Grenfell Tower, where an external insulation cladding package from the very bottom of the market became an accelerant wrapped around hundreds of homes, killing seventy-two people.

But a remarkable project in the outskirts of Paris suggests another way, neither demolition nor dangerously ‘value-engineered’ sticking plasters. La Tour Bois le Prêtre is a 1959 tower block of sixteen storeys and ninety-six apartments on the Peripherique of Paris. A cheap 1990 facade replacement was already at the end of its life, so the writing was on the wall for demolition.

However, in 2011 the French architects Anne Lacaton and Jean-Philippe Vassal proposed another approach, one that could conceivably change how ageing tower blocks are treated across the world. Their idea for the tower was superficially simple: take the facade right off the building, and then build a lightweight free-standing structure around the outside, giving every apartment in the tower a balcony and winter garden that offered better views, improved the thermal performance, and most importantly gave everyone a brand new room.

Sounds like a great idea, so why had no one done it before? Mainly because the assumption would always be that this was an expensive option, and it would always be cheaper to demolish the tower and relocate the residents. Lacaton and Vassal had to prove not only that their project would save money, but also that it could be achieved without moving anyone. A system had to be designed where the flats would remain intact and usable until the moment the new structure was connected, which meant lots of extra design labour, detailed sequencing of works to keep everything in order as the new addition grew, and tight control of material costs to maintain viability.

The result is a building that is an incredible 30 percent bigger than it was before, and is still home to its long-term tenants. It looks cheap, of course, but the years spent refining their technique means the architects have provided a robust aesthetic that allows the residents’ tastes free rein, and an elegance that is a massive improvement from its previous guise.

The entire project cost €11 million, which is far less than the costs of demolition and construction of low-rise replacement houses. Lacaton and Vassal themselves now have a number of projects across France where the process is being repeated, and other architects and clients are learning from the technique. The success of this project highlights the inadequacy of current attitudes to social housing stock, where communities are treated with potentially deadly contempt, and authorities are in thrall to the desires and demands of developers.

In recent years, hysterical anti-high-rise rhetoric has calmed somewhat, but what is left is severe class prejudice: new sixty storey luxury residential towers in banking districts are fine, but existing communities are still being removed and scattered. Lacaton and Vassal’s approach has shown that imagination and commitment can offer a more dignified solution for everyone.