What signs of mould should you look out for when you are viewing rental properties?

Black mold in the corner of room wall

As the mould crisis in the UK continues, you may think that residents in social housing are the only people at risk from exposure. This is not the case, in London alone 51.06% of tenants report to have mould and 74.07% of homeowners have experienced mould in their homes*. So, how if it can happen to anyone, can renters reduce the risk of living in a home with mould?

How landlords try to avoid the issue

Jennifer Ross

Here is a real life example of a nightmare scenario for younger renters in the capital which highlights how a bad landlord will try to avoid dealing with a mould problem.

Jennifer Ross (27, pictured above) is an account manager for a London based healthcare communications agency. While she was living in a shared flat in Tooting London Jennifer and her flatmates paid £2420 per month rent. The flatmates moved into the flat in October 2021, but by Christmas as the weather turned colder they noticed mould starting to appear through the flat’s newly painted ceilings.


Alerting their  landlord to this issue straight away, initially he did not respond so they tried to solve the problem on their own. They mopped the ceilings with bleach. However their efforts always failed and the mould would aggressively grow back.

The landlord later agreed to repaint the bathroom. This did not improve the underlying issue in that the black mould was still there and the mould was extending into other rooms in the flat too.  The source of the damp and mould issue was identified in spring 2022 as the back bedroom started to leak in rain.


The roof got fixed and warmer weather momentarily solved the problem, but as the weather turned colder the mould reappeared. Sadly the landlord continued to ignore Jennifer’s  requests for help so after two years the flatmates decided to leave in October 2023.

New tenants live in the flat now and the mould has worsened, even worse news is the new tenants pay an extra £1000 a month and the landlord continues to avoid their requests for help.

What impact can Mould have on tenants?

NHS UK states: “People living with mould are more likely to suffer from respiratory illnesses, infections, allergies or asthma.”

A recent BBC Report concluded:

“Inhaling or touching the spores that mould releases into the air can cause an allergic reaction, such as sneezing, a runny nose, red eyes and a skin rash.

“Mould can also trigger asthma attacks and cause coughing, wheezing and breathlessness.”

Nobody should have to live with this level of toxic mould in their homes and landlords need to be ready to tackle the problem straight on.

Often damp problems aren’t found until it’s too late and tenants have signed the contract and moved in.  New proposals are expected to tighten up the rules regarding rental properties, but until then, it is often a case of ‘renters beware’.

What should prospective tenants look out for?

There are red flags that tenants can look out for when viewing properties to rent.  Look out for these signs when checking for damp in a rental property:

  • Discolouration on walls, peeling paint or wallpaper
  • Black mould on window seals- particularly in the bedroom and bathroom
  • Black mould on ceiling in the corners of rooms
  • Excess condensation – streaming windows, mirror
  • Musty or damp smell
  • Stains on walls
  • Smell of fresh paint (this can be evidence of someone painting over visible mould)

What can landlords do?

Awaab Ishak, a two year old Rochdale boy, died in 2020 after prolonged exposure to mould in his home.  Mould exposure can be fatal and has serious consequences, but there are sound business reasons apart from health of their tenants for landlords fix any problems fast.

As landlords shy away from their tenants’ issues, they are allowing much bigger structural damage to develop. Mould can be extremely aggressive and prevention is always better than cure, but should a property start to show signs of mould, landlords should treat the area immediately, review why the mould is happening and for the price of a bottle of HG mould remover spray there can be huge savings in the cost of tradesmen.  However, if the mould is prolific, seek professional advice asap.

Bottom line, one way or another, once mould develops, it will eventually need to be fixed to protect your property investment – why not do it promptly, keep good tenants and maintain the value of the property?

*Airfresh (London Mould Report)