Is your garden on “brownfield” land? Then it could be targeted by the garden-grabbers, the nickname earned by developers who are looking for somewhere to build housing schemes.

The practice is happening all over the UK, but is becoming increasingly prevalent as housebuilders look to build smaller developments. This allows them to circumvent planning laws, which require large schemes to provide a certain percentage of affordable units for low-income earners and first-time buyers. Developers prefer to reduce the number of affordable homes because they are less profitable than those sold on the open market. Hence, the appeal to developers of large private gardens.

Garden-grabbing has become a major policy issue in areas where homeowners are particularly susceptible to approaches. Last month a Private Members’ Bill by the Labour MP Andrew Dismore was the latest of at least four Bills in recent years aimed at banning the practice — none of the Bills have become law. Boris Johnson, the Mayor of London, declared in the recently published London Plan that the capital’s gardens will no longer be classed as brownfield land.

Part of the problem is the Government’s own housebuilding targets. It has pledged to deliver three million homes in England before 2020, and has promised to increase the number of homes available each year by 240,000 until 2016. It is so far woefully behind these targets, and local councils are under pressure to alleviate the shortage. The lure of cash on offer from opportunistic developers is dividing local communities — some neighbours are accepting the money, some aren’t and do not want their neighbours to either.

The effect of this is clear in Pegwell, near Ramsgate, Kent, where Thanet District Council identified the extensive gardens of two houses as a potential two acre-plus development site. Current policies allow land agents to approach owners of properties near designated development land asking if they would be interested in selling. The result in Kent was that four householders expressed an interest, leading to suggestions that up to 40 houses might be built on the combined site, and a row that set neighbour against neighbour.

David Pownceby, the developer of the scheme in Pegwell, is dismayed by the label of garden-grabber. He was under the impression that the local council wanted to provide higher density housing on every site to meet targets. However, proposals for high-density housing schemes are now being rejected by elected council members. His company, Lilybrook Developments, bought the designated housing site, then faced a protracted dispute about what sort of housing would be suitable.

His latest scheme, which is subject to consideration. comprises 14 three-storey £450,000 houses — a far cry from the council’s idea of providing a mixed development that would include affordable homes and far fewer than the 40 originally planned. “We were told we couldn’t go below 40 houses, then it was 30 houses, then we settled on 26, nine of them as affordable homes. Now we’re down to 14, none of them designated as low-cost,” he says. “It is an example of how planning policies need a complete overhaul.”

Simon Thomas, senior planning officer for Thanet District Council, says that the council was under pressure to identify development land: “According to the government plan, there is a requirement for 7,500 additional homes in Thanet.” However, councils are also obliged to ensure that new developments are not so dense that they are considered over-crowded. Guidelines state that builders should aim for 30 dwellings per hectare. Marion Pearce, a local resident, has led a ferocious campaign against the Lilybrook development. “These were lovely gardens, sacred little spaces that have been lost for ever,” she says. “Even now, I wouldn’t be surprised if these 14 three-storey units turn into flats.”

There are dozens of similar rows going on around the country. Kingston upon Thames council, in southwest London, lost a planning appeal against a proposal to squeeze seven houses on the gardens of two properties in a street in Chessington, Surrey. Guildford, Surrey, is facing a massive concreting over of gardens in the attempt to increase the number of homes in the town by almost one third.

Greg Clark, the Tory MP for Tunbridge Wells, calculates that in six centres, including Oxford, Nottingham, Chelmsford and Bradford, nearly two thirds of newly built homes are on former garden land. “You can’t necessarily blame developers or people who sell their houses to developers,” he says. “It is a problem of national planning regulations and housing density targets, which take away a lot of the local decision-making.”

The Government maintains that most new developments are on former industrial sites. However, the Communities and Local Government department has embarked on an investigation to find out how much development on land that was formerly gardens is being approved.

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