Studio flats that are smaller than rooms in a budget hotel are set to be squeezed into an 11-storey block in north London.
Plans for Barnet House, used by the London borough of Barnet's housing department, show that 96% of the 254 proposed flats will be smaller than the national minimum space standards of 37 sqm for a single person.
The very smallest will be just 16 sqm, which is 40% less than the average room in a Travelodge.
They are legal because of government deregulation designed to promote the conversion of underused office space to help meet housebuilding targets.
Conservative-controlled Barnet council, is opposed to the development which locals have compared to 'dog kennels and cages', but says its hands are tied by national government policy.
Council leader Richard Cornelius, said: "It is always difficult for a local authority when something is happening in its area over which it has no control. The government has given developers power to convert businesses premises into residential premises under permitted development.
He added: "The sizes of some of the flats would not be what we think are appropriate living spaces for our residents and we do not support the scheme in its current form."
The flats will contain basic furniture, such as a small kitchenette, bed and wardrobe, but the smallest flats will have very little room to move around. There will be very little space for example, for a sofa or a washing machine, unless it is stacked on top of the fridge.
Speaking to the Guardian, Graeme Brown, interim chief executive of Shelter, said: "In theory, converting offices sounds like a good way of creating some of the homes we need in a time of crisis. But in reality, it's often used by developers as a way of cashing in on people's desperation by building unaffordable, rabbit-hutch homes.
"Our homes are already among the smallest in Europe, and if the government allows developers to cut corners by slashing space standards in homes even more, they will be punishing ordinary families in the process."
Studio flats of a similar scale in the surrounding area sell for around £180,000 and rent for about £800 per month.