'Billionaires own my mouldy rental property'

"I fear for his health because I know once it comes back, his health starts to deteriorate all over again," says Sinead as she shows us the mould staining the walls of the flat she shares with her son.

When she and five-year-old Aziyah moved into their home in Brighton in 2020, it seemed in good condition. But black mould quickly began to appear. Over the next two years it spread all over the walls, even onto the beds and furniture.

The 25-year-old, who privately rents for £1,100 a month, initially reported it to her landlord, but despite their attempt to improve ventilation, the problem remained. A year later, Aziyah began to develop health issues and was later diagnosed with asthma.

Five years since it all started, despite repeated complaints to her landlord and her local council, Sinead's mould problem has not been solved and she feels trapped.

"No matter how loud I scream, I'm not being heard," she says.

More than half a million rented homes - both private and social - have black mould issues in England, a 2023 government survey found.

Aziyah once had a persistent cough for eight months

In Rotherham, we met an elderly couple who have lived in the same privately rented house for more than 50 years. It has peeling wallpaper, wet walls, large black mould patches and an overwhelming smell of damp.

When asked what effect it is having, 82-year-old Christine Brown told us: "Do you want the truth? I just wish I were dead. That's how it's got me."

Christine, and husband Paul, 74, have a protected tenancy which keeps the rent low, at £440 per month. They did not know who their landlord was. All communication was through a letting agent.

After some digging, Panorama discovered the house is owned by a large property company, run by a billionaire family.

Christine suffers from asthma, angina and bronchitis and Chronic Obstructive Pulmonary Disease (COPD), a progressive lung condition she believes was caused by the mould.

Sinead's landlord installed extractor fans and provided dehumidifiers after she complained to the council

Mould exposure can badly affect people with COPD or asthma as it can trigger an irritant response.

"Your airways close up, you start coughing," says the chair of the Royal College of GPs, Kamila Hawthorne. "There's more chance of you picking up an infection and you're more likely then to need antibiotics and/or steroids - and possibly even a hospital admission."

More than 26,000 babies and toddlers were admitted to hospital last year with lung conditions probably linked to exposure to damp and mould, Panorama analysis of NHS England data has found.

After two-year-old Awaab Ishak's death in 2020 was found to have been directly linked to mould exposure, the then-Conservative government drew up a new law in his name to protect social tenants in England from unsafe living conditions. But the legislation is yet to come into effect.

The government announced the law will be enforced for damp and mould problems from October - and fully implemented for all other hazards by 2027. Private renters will be protected in the same way - says the government - once its Renters' Rights Bill becomes law, expected later this year.

In Awaab's case, his father Faisal had repeatedly raised the mould problem with the housing association responsible for the family's Rochdale flat, but no action was taken.

Faisal is frustrated the change has taken so long. "They should bring it through as soon as possible," he says. "It's going to be saving a lot of people's lives."

Aziyah has been referred to a lung specialist

In Brighton, as Aziyah's health worsened, Sinead says she was "really scared" and "feared for his life".

"He was coughing and vomiting," she says, which medical records show had led to dangerously low blood sugar.

At another point, he had a persistent cough for eight months. "He said, 'Mummy, how do you stop this coughing?' And I said, 'You can't, Aziyah,'" says Sinead.

After she complained to the council - which is responsible for ensuring landlords maintain housing standards - the landlord installed extractor fans and provided dehumidifiers. But the mould remained.

In many cases, local authorities are not enforcing private landlords' legal duty to maintain safe housing.

We asked every local authority in England and Wales for the number of complaints they had received about housing issues and what enforcement action they had taken. In the past seven years, there were more than 570,000 complaints (from 255 council responses, after 317 requests) about privately rented homes.

In more than 90% of cases, no action was taken and fewer than 1% of complaints resulted in a landlord being prosecuted.

Councils are facing significant ongoing and historic challenges with resourcing, says the Local Government Association that speaks for authorities in England and Wales. "Issues may be resolved without the need for inspection, with enforcement and prosecution being a last resort when all other options fail," it adds.

Over the past 10 years, council funding in England has gone down by 10% in real terms, according to the National Audit Office.

"There is a perfect storm now happening, some of which is around really stretched funding, some of which is around the age of homes," England's Housing Ombudsman Richard Blakeway says.

In England alone, more than three million households are estimated to be living in properties that do not meet the government's decent homes standard, according to a government survey.

The homes are either in a state of disrepair, do not have modern kitchen and bathroom facilities, or lack adequate heating and insulation.

Paul and Christine did not know who their landlord was

When Christine shows us around her privately-rented home in Maltby, Rotherham, there are visible issues with damp in every room.

"I'm sick of seeing it like this. My house has never been like this. When I was younger and working I could do it [repair the house] myself," she says. "We just can't do it now."

The couple say they first told their managing agent, Savills, about the problems in 2022.

Savills says it authorised work for the house, including having the roof resurfaced in 2023 - but water is still getting in, including from the adjoining property, and many other problems remain.

BBC Panorama wanted to find out who was ultimately responsible for the condition of the home.

It is owned by a company called Area Estates Ltd, which Companies House records show is part of the William Pears Group. Two of the three brothers who are directors of the group live in some of the most expensive postcodes in London.

One of them, Mark Pears, is also on the 2024 Sunday Times rich list, with an estimated family wealth of more than £3bn. He is also a trustee of the British Museum. His brother and fellow director Sir Trevor Pears was knighted in 2017 for his charity work.

Area Estates told us it had authorised professional managing agents "to look after the [Rotherham] property in accordance with all regulations", and to "carry out day-to-day maintenance", and that requests for more expensive repairs were always responded to quickly.

"The managing agents will reinspect the house shortly and attend to any repair issues found which are the landlord's responsibility," it added.

Managing agent Savills said it was "very sorry to learn that Mrs Brown believes that complaints have been in any way ignored". It said it had always attempted to address any problems in a timely manner - and had completed 13 different inspection and repair works at the property between 2023 and 2024.

When BBC Panorama told the couple about the identity of their landlord, Christine said: "I'd shake his hand and I'd say, 'please make my house safe'."

"I'm sick of seeing it like this," says Christine

In Sinead's case, while council environmental health officers said there were problems, they concluded the flat was safe. She then secured legal aid to pay for an independent inspection. It said the flat was "unfit for human habitation".

Sinead also applied for social housing, submitting evidence about Aziyah's health. But the council said he had not had "frequent A&E visits with hospital admissions and complex treatment".

Brighton and Hove City Council says the issues it has the legal power to enforce at Sinead's flat have now been addressed by the private landlord. It says it has also recommended improvements to "ventilation and insulation" that it "can encourage but cannot enforce".

Sinead's landlord accepts that "there is a problem with condensation" but says the continuing issues are "due to neglect" by her not clearing away condensation.

Keeping a consistent temperature and ventilation can help prevent mould growth - but it will not solve the problem if faults with the building mean there is poor ventilation or damp is coming in.

Meanwhile, despite the flat having been cleaned and repainted last summer, the mould is coming back.

Aziyah's cough still hasn't cleared up and he has been referred to a lung specialist.

"It's my son that keeps me going," says Sinead. "If I don't fight this, then who will fight for him?"

Update: This article has been updated to make clear that more than three million households are estimated to be living in properties that do not meet the government's decent homes standard. It originally said three million social tenants.