Disabled children and former Grenfell residents are among social housing tenants being blocked from communal gardens, entrances and a car park on a multimillion-pound development in west London.

Guardian Cities has learned that the housing association Octavia blocks access to the communal gardens of Westbourne Place in Maida Vale for social and affordable housing residents in order to avoid the tenants facing the “financial burden” of high service charges. Service charges were originally set by the developer Redrow and are now managed by Pinnacle Property Management who run the private side of the development.

My seven-year-old has a best friend in his class who lives on that private side. They sit in school together but can’t play together Ahmed Ali

Redrow’s original plans for the luxury flats, as approved by Westminster council, appear to show open access to the gardens for all who lived there. The plans are now the subject of an enforcement investigation by council officers. Redrow – who have now sold the freehold – marketed the homes, which were sold at around £750,000 as “statement living at its best”.

A fob-controlled gate stops social and shared ownership residents entering the gardens, while private owners have fobs which allow access across the whole development.

The affordable and social residents, who pay over £200 a month service charge per home, have told the Guardian they feel the situation is unjust and discriminatory. One family with a disabled child say they have been fighting for much needed parking access from Pinnacle for several months.

Timeline Too poor to play – a timeline Show Investigation reveals segregated play spaces Guardian Cities reports that children in social housing on the Baylis Old School site in Lambeth, south London were blocked from using shared play spaces and communal areas on the site. The estate is a mixed-tenure development, meaning that in order to get planning permission the developers had included some social and affordable homes. Condemnation across political spectrum There was widespread condemnation from across the political spectrum, with Conservative housing secretary, James Brokenshire, calling the situation “outrageous” and the Mayor of London, Sadiq Khan ,saying "the developer should put an end to this shameful practice immediately”. Developer Henley Homes announced that “all children are welcome” on the site. Shortly afterwards Lambeth council workers demolished the wall that had been blocking access. More segregation emerges Our followup investigation identifies half a dozen mixed-tenure developments across London – most of them relatively new, or featuring recent conversions of older buildings – that separated play areas for richer and poorer children, often with hedges or other barriers. Mayor of London bans future segregation The mayor of London announced that he would be banning segregated playgrounds in all future developments in London. Khan said: “It is disgraceful that children who live in the same development would ever be prevented from playing together.” Housing secretary condemns segregation Housing secretary James Brokenshire says that any segregation by tenure is wrong. “These cases that have been brought to our attention – whether it is playgrounds or the concept of a poor door – where your access to a building is determined by your ownership, this cannot be right,” he told the BBC. Brokenshire, who was later replaced by Robert Jenrick, called for developers to open spaces up in estates that are currently segregated and that would not be covered by a future ban. Grenfell family in segregated development Guardian Cities discovers that children in social and affordable homes on the multimillion pound Westbourne Place development in west London are not allowed to use the main gardens on the site and their parents are not allowed to use the car park.

The news comes despite widespread outrage sparked by a Guardian Cities investigation in March that discovered children living in social housing in Lambeth were banned from using a communal play area. After follow-up stories revealed the full extent of the problem across London, mayor Sadiq Khan announced a ban on segregated playgrounds in all future developments, describing them as morally unacceptable. The then-housing minister, James Brokenshire, announced he would like to see all forms of housing segregation driven out across Britain.

A publicity image of Westbourne Place, taken from Redrow’s website. Photograph: Redrow

Hamid Ali Jafari lost his 82-year-old father, Ali Yawar Jafari, in the Grenfell Tower blaze. Together with his mother, wife and baby son, he was rehoused into the then newly built Westbourne Place. He is not allowed to use the large garden overlooked by his flat, and is desperate to move before his son gets older.

“He asks all the time if he can play football in the garden,” Jafari said. “Luckily he is only five so I can try to distract him and say we should play somewhere else. If he was a bit older he would know what was really happening.

“It’s just very disappointing, to be honest, to live like this. I am already suffering with depression from what I went through at Grenfell.”

His neighbour Ahmed Ali has been complaining for several months to Westminster council, Redrow, Pinnacle and Octavia about the segregation.

“My seven-year-old has a best friend in his class who lives on that private side,” Ali said. “They sit in school together but can’t play together. Private residents have access to everything, they can use all the gates and they walk through our side all the time, they exercise their dogs over here. This is open discrimination. We work, we pay service charges, we pay rent, we don’t deserve to be treated like this.”

Ali’s younger son is seriously ill with a life-threatening condition and Ali has to make regular trips to the local paediatric intensive care unit.

“I’ve told them about my seriously ill son but Pinnacle [which manages the private side of the development] won’t let me park on site or let me come in the main entrance, which is nearer the street disabled bay. Instead I have to carry my sick child in the rain and cold all the way round the building.”

Children on the social housing side of Westbourne Place climb the gate that prevents access to the development’s communal gardens. Photograph: Graeme Robertson/The Guardian

One mother, whose children were playing in the small area allocated to social housing residents, said the way private owners can move freely through the social housing side is unjust. “The private residents are allowed to walk through here, they bring their dogs into our play area and let them off the leash, but we aren’t even allowed to walk through there,” she said.

The Guardian asked Octavia if they have made any attempts to negotiate lower service charges or better access for its tenants. A spokesperson replied that although they did not know what the extra cost would be, they did not want to impose a burden on their residents, saying: “The running costs at this development are quite high, as they are with many new developments of this type.

“Access for our residents to the private sale part of the development and the parking area was not part of the offer from the developer and it was not sought in our lease negotiations, as it would have put an added financial burden on all residents in terms of service charge costs. Keeping costs like this down contributes to making housing more affordable. We are challenging the current access arrangements to parking with the management agents.”

Between them the affordable and social homes are paying around £36,000 a year in service charges. Ali and his neighbours say they have offered to pay extra to use the garden but had no response. They have not been given any information on what the garden costs to maintain.

In a statement, the deputy mayor of London, James Murray, reiterated Khan’s view that service charges should not be used to segregate residents from communal gardens or play areas.

Any designs that divide communities – from segregated spaces to poor doors and exorbitant service charges – have no place in our city James Murray

“Segregation has no place in London,” Murray said. “Developers considering any form of separation or distinction between social and private housing need to realise their position is morally unacceptable. Any designs that divide communities – from segregated spaces to poor doors and exorbitant service charges – have no place in our city.”

Councillor Adam Hug, leader of the Labour group in Westminster, said the council had been under the impression at planning stage that all residents would have access across the site. “My argument is that the onus is on the developers, Redrow, in this situation,” he said. “If they are setting the service charge too high for Octavia to allow access then I believe that is a breach of the original planning permission that shows open access.

Redrow, which posted profits before tax of £380m in 2018, and which advertised the site as “a distinguished collection of 49 luxury residences” said that the decision to segregate the site by tenure lay with Octavia, who wanted to keep costs down.

Mark Parker, regional managing director for Redrow in London, said: “We strive to create inclusive developments and work closely with the managing agent in the early stages and assess their recommendations on service charge levels for residents. We always endeavour to keep charges as low as possible for all parties.

“This particular block … is owned and controlled by Octavia Housing. Octavia sought to minimise service charges by specifying the areas that their residents would require access to within the development.”

“We no longer own the freehold of this building. Residents should raise their concerns with the managing agents concerned and Octavia Housing.”

Pinnacle, which manages the private side of the site, including parking, said in a statement: “We manage the development [on behalf of Westbourne Place Management Company Ltd] in accordance with the provisions set out in the leases which were agreed between Octavia and Redrow Homes prior to completion.”

Westminster Council has opened a planning enforcement investigation to examine whether Redrow are in breach of the original planning permissions.

• After publication, Octavia supplied the following statement: “Our position is that we would very much like our residents to have access to those gardens and we think it is wrong that they are restricted in this way. This is not a result of a decision we have made. It is a result of a decision taken at some point in the development of the scheme.”

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