An overwhelming majority of UK social landlords report having mould issues in properties under their remit, according to new research out today – and the results reveal that landlords are at a loss on how to deal with their mould-ridden properties.

The study, conducted by indoor climate solutions provider Zehnder Group UK, polled both social housing landlords and tenants to find out to what extent they are suffering with mould and condensation in their homes. The findings revealed that 99.2% of landlords have mould problems in their housing stock and almost a third (32%) of tenants reveal their homes have mould present in 5-6 rooms.

More than 1 in 10 landlords claim that mould affects over half of their housing remit and believe that the main root cause of the mould is simply down to the weather (41%).

Within the study, questions were asked to understand more about the mould problems landlords and tenants face, how widespread the problems are, how it is currently being dealt with, what help they seek as well as any barriers to change. Other root causes are believed by landlords to be old buildings (36%), humidity (34%), condensation (28%), poor ventilation (23%), recent insulation of the house (22%) and general damp (17%).

While they have tried multiple strategies to solve the problems, landlords admitted that while some of these methods worked for a time, the mould came back (51%) or the approach didn’t work at all and the mould is still there (16%).

When asked how the returning mould makes them feel, over two thirds of Landlords admitted to feeling frustrated and angry (64%), over half feel worried and scared (57%) and a third feel embarrassed (30%).

Commenting on the findings, Zehnder RMI National Manager, Mark Trowers, says: “While a third of landlords in our survey are approaching this widespread issue in the right way by installing better ventilation or calling in an expert (29%), others are following generalist advice that won’t solve the root cause of the problem, either temporarily fixing it, or not fixing it at all. These include applying anti-fungicidal wash (28%), using an anti-mould spray (25%) or bleaching the area (24%). A quarter of landlords we surveyed claimed they asked the occupants to change their living habits, yet large numbers are still just washing it off with soapy water (21%) or painting over it (17%), so it isn’t surprising the mould comes back.

“Mould outbreaks are caused by excess moisture build up in the property and lack of adequate air flow to ventilate that moisture effectively, causing condensation to form on cold surfaces, turning water vapor into liquid. Routine activities such as boiling the kettle, cooking, bathing, showering and even breathing can produce significant amounts of water vapour – up to 24 pints per day for the average family. The conditions created by condensation provide the perfect environment for mould and mildew to develop – creating conditions for dampness and toxic black mould to takeover and spread, which poses serious health risks to humans.

“In our study, over half of tenants (54%) admitted to turning off the extract fans in their bathrooms and kitchen, which is often the only form of ventilation in the property. Yet the reasons for doing so are rooted in a lack of understanding, with 36% claiming heat loss from the fan, running costs (34%), noise (33%) and nearly a fifth (18%) claiming they just don’t need them.”

The task of solving the problem appears insurmountable as 46% of tenants living in social housing claim to have mould present in 3-4 of their rooms. Almost a third (32%) have mould present in 5-6 rooms, 12% have it in 1-2 rooms and 1 in 10 tenants reveal their properties are riddled with mould throughout (7-8 rooms).

The mould doesn’t just affect the wet rooms in these properties but worryingly also living and sleeping areas:

Wet rooms only (bathroom / shower room) (40%)

Main Bedroom (32%)

Dining Room (30%)

Children’s bedrooms (28%)

Living Room (25%)

Kitchen (25%)

Understandably an overwhelming 98% of tenants worry about the mould that is in their home with their health (21%) and children being exposed to it (21%) being their top concerns, along with the mould affecting allergies (21%) and having to constantly clean (21%). One in five spend money repainting and worry that their possessions are being ruined, while 19% worry it looks horrible. 16% are even worried that the walls or ceiling will fall down.

Barriers to solving the problem

A third of landlords see technology (37%), cost (36%) and lack of knowledge / understanding (31%) as a key barrier to solving their mould problems. Just under a third claim local authority (29%) and lack of support (28%) as a key barrier.

Almost a third (27%) claim the property occupants are a barrier and 98% of landlords think the problems with mould are associated with a lack of education for occupants in how to live healthier in their home (e.g. drying washing inside, turning off the fans, keeping windows closed).

But tenants aren’t helping matters by not speaking to their landlords and turning off what ventilation they have that could help the situation. Over a quarter of tenants (28%) have not sought external help in solving the mould outbreaks in their home and 83% of tenants have not spoken to their landlords about the mould issues.

“Managing condensation in homes, particularly in social and rented housing, requires a multi-faceted approach and the right balance of heating and ventilation,” Mark Trowers continues. “Upgraded insulation must be considered in partnership with an effective ventilation system to help regulate indoor humidity levels and promote a healthy indoor environment, minimising the conditions conducive to condensation. Without it, we risk living in airtight boxes that turn bad in time.

“Extractor fan technology has come a long way in recent years and no resident should feel the need to turn off their fan due to noise or cost. In fact, to run a modern Zehnder fan, 24-7, 365 days with two hours of humidity boost per day, can cost under £1.65 per year*.

“As an industry, we need to help landlords navigate this epidemic and arm them with information and tools available to make their properties healthier – we are part of a bigger and quite complex puzzle where education, accessibility and collaboration is key.”