Identify and prevent damp, mould and condensation in your property - Total Landlord Insurance

October 23, 2023
Identify and prevent damp, mould and condensation in your property - Total Landlord Insurance

Read an interactive and user-friendly version of this guide below.

In 2022, according to the 2021-22 English Housing Survey, problems with damp were most prevalent in the private rented sector, with 11% of homes having reported problem in 2021, versus four per cent of social rented housing and two per cent of owner-occupied homes.

The previous English Housing Survey stated that part of the reason why such a relatively high percentage of properties in the private rented sector are affected is because they are, on average, older. That means they’re more likely to have failing damp proof courses and damage to the fabric of the property that could lead to damp problems – particularly if landlords aren’t on top of maintenance and repairs.

Another reason why damp, condensation and mould are common issues in rented properties, is that tenants might not ventilate their homes properly and might fail to report problems at an early stage. If they’re not dealt with quickly, damp and condensation can both lead to mould forming. And if mould is allowed to grow and spread, it can be damaging, both to your tenant’s health and the property.

But whose responsibility is it to deal with damp and mould issues in your rental?

The answer is that it’s your job to put things right, regardless of who you believe might have caused the problem in the first place. That’s because, as a landlord, you’re legally obliged to maintain your tenant’s home in a good state of repair, and that includes making sure it’s kept free from damp and mould.

Government guidance on damp and mould

On 8 September 2023, following the tragic death of two year old Awaab Ishak in 2020 due to prolonged exposure to mould in his family’s housing association home, the Government published comprehensive guidance on damp and mould in homes. The aim of the guidance is to make sure that both social and private sector landlords have a thorough understanding of their legal responsibilities and the serious health risks that damp and mould pose.

The guidance explicitly states that tenants should not be blamed for damp and mould and that it is the responsibility of landlords to identify and address the underlying causes of the problem, which may for example be structural or inadequate ventilation.

Responding to the guidance, Sean Hooker, Head of Redress at the Property Redress Scheme, said:

“It is no longer acceptable to blame issues on the way tenants live, as normal life such as cooking, washing and drying of laundry have to continue. Instead, landlords and their agents must be sensitive to the needs of tenants and work with them to understand and change behaviour where appropriate. They should also thoroughly investigate the underlying causes behind the problems and follow up to make sure things have improved.”

Sean Hooker, Head of Redress at the Property Redress Scheme

It's important that landlords read the guidance, which states:

“Landlords must ensure that the accommodation they provide is free from serious hazards, including damp and mould, and that homes are fit for habitation. They must treat cases of damp and mould with the utmost seriousness and act promptly to protect their tenants’ health.”

The guidance offers an overview of what landlords should consider when addressing reports of damp and mould and provides examples of best practice to help reduce the health risks to tenants and potential damage to the property. The guidance also includes advice on responding to reports of damp and mould and how to take a proactive approach to reducing the risk of damp and mould.

Damp and mould growth is one of the 29 recognised hazards under the Housing Health and Safety Rating System – see GOV.UK for guidance for landlords on this – and landlords are ultimately responsible for making sure their property is free from hazards, so must attend to any structural defects of disrepair that may cause the growth of damp and mould.

However, condensation due to a lack of ventilation or lifestyle factors can also cause damp and mould, so it’s important that landlords communicate with tenants. This will help them understand what steps they can take to reduce condensation in the home, thereby reducing the risks of mould or damp growth.

What is condensation?

Condensation is a common occurrence in many homes. It forms when warm, moist air produced by everyday tasks – such as cooking, showering and drying clothes – can’t escape from a room and reaches a cold surface. The difference in temperature causes the warm air to condense into water droplets that collect on these cold surfaces, commonly windows and walls.

If these water droplets aren’t wiped away, tiny mould spores in the air can land on the moist surface and begin to grow as mildew, also known as ‘surface mould’.

The main causes of condensation

There are three main causes of condensation in a property:

  1. The room temperature is too cold, meaning any warm air created is likely to condense
  2. There is a lack of ventilation in an area of high steam production, such as kitchens and bathrooms
  3. The property generally has an excess of moisture-rich air – for instance, due to the number of occupants or because a lot of washing is being left out to dry

Other factors that can cause condensation:

  • Lack of insulation at construction – older buildings may not be well enough insulated, meaning the interior walls may be colder and more susceptible to condensation
  • Cold spots/bridging – some materials used during construction are naturally colder than others, such as concrete beams, which can be difficult to insulate adequately
  • Colder weather – condensation is more common during cold weather and is more likely to collect in areas where there’s not much air circulation, such as behind furniture

How to prevent condensation

Preventing condensation in rented properties relies on the efforts of both landlords and tenants. Landlords have to make sure that the property remains in good condition with all the fittings and services working properly, and the tenants need to do their part to be considerate while living there.

For example, if an extractor fan is poorly fitted and not working well enough to remove steam from a bathroom, that’s a failing on the landlord’s part. But if condensation is causing surface mould to form in bedrooms because tenants are drying washing in there and not opening the windows, they could be causing the problem.

Although it’s down to you as the landlord to fix all damp and mould problems if they do occur, if you are able to prove that the tenant either directly caused the issue or made it worse through not reporting it early, you may be able to reclaim some of the cost of repairs from their deposit at the end of the tenancy.

“Tenants should be encouraged to always report any issues they find at any point during the tenancy, to give the landlord an opportunity to investigate and address the problem at the time, and to avoid it getting worse. It is important to do this in writing so there is an audit trail if it does, at any point, become an issue.”

Suzy Hershman, Department Lead at mydeposits

See our deposit protection partner, mydeposits, separate article on understanding damp, mould and condensation: how to avoid deposit issues, for more information and read mydeposits case study on damp and mould here.

Nevertheless, it should be possible to avoid most condensation issues by reminding tenants of the simple steps they can take. We’ve put together a tenant checklist for you to share with your tenants to help them recognise what type of damp or mould you might have, what you can and should do about it, and how they can prevent it. Download a printable version to share with your tenants here.

Top tips to reduce the chance of condensation becoming a problem

As the landlord, two key steps for you to take are:

  • Make sure your rental is properly insulated – see our guide to having an energy efficient, eco friendly property for detailed information and advice
  • Make sure that the property can be well ventilated, with trickle vents in double-glazed windows and efficient extractor fans in areas where a lot of moisture and steam tends to be produced, such as the kitchen or bathroom

Then we’d recommend you pass on the following tips to your tenants:

Avoiding condensation and mould in your rented property

  • Always use extractor fans where they are provided and report any problems with them right away
  • Air the property as much as possible by opening windows, when safe and suitable to do so – even if it’s just for a short time every day
  • Close off any moisture or steam in a room to stop it spreading through the property, for example by keeping the bathroom door shut during and after a bath or shower. Having a bath produces around two pints of moisture, a proportion of which could be circulating around the house!
  • Avoid drying wet clothes on radiators and keep the space around them clear so the warm air can circulate properly
  • Make sure any room used for hanging out laundry is well ventilated
  • If condensation does collect on window sills or other surfaces, wipe it away to prevent mould forming
  • Keep the thermostat at a minimum of 15°C in very cold weather – not only will this help reduce condensation levels in the property, but it will protect the pipework from freezing

And emphasise to your tenants the importance of letting the property manager know as soon as any problems arise, so they don’t become long-term issues.

If you (or your managing agent) are notified about a condensation or mildew problem, address it right away and confirm the action and timeline required to deal with the problem in writing. Not only will this make sure it doesn’t develop into more serious mould growth, but your tenants should appreciate you being responsive and may be encouraged to be more careful about ventilation and cleaning in future.

Dealing with damp problems in your property

Where condensation is mainly caused by everyday activities in the home, dampness is usually a result of building defects. That means tenants really have no control over damp and it can be a problem even if they’re ventilating and heating the property adequately during their tenancy.

There are three key reasons damp needs to be addressed:

  1. Prolonged damp exposure can lead to structural issues with the property, so acting sooner rather than later is extremely important
  2. Damp walls act as a heat conductor, which can sap warmth from a room so tenants will feel colder and may have to spend more on extra heating
  3. Damp surfaces attract mould spores, which can be extremely unsightly and may pose a risk to your tenants’ health

The two types of damp

Rising damp  

This is where moisture in the ground is gradually absorbed into the floor or walls of a property and it’s what damp proof courses are designed to prevent. Rising damp usually affects older properties over time, where damp proof coursing or membrane was never installed or has failed. As the moisture rises up through the mortar and masonry, it appears on the inside walls of the ground floor, up to a height of about a metre.

Penetrating damp

This is where water leaks into the property from outside, usually through cracks in the brick work or tiles. If there are damp patches on the upper walls or ceilings, it will be penetrating damp.

It can come from a variety of sources, including:

  • blocked or broken guttering that causes rainwater to run down the outside of the walls and gradually seep inside
  • external plumbing issues – cracked or weathered piping introducing water into the property
  • gaps or cracks in a window frame
  • faulty construction, e.g. a basement not being properly waterproofed

With both types of damp, it’s important to identify and treat the cause as soon as possible, to avoid further damage and make sure your tenants’ health isn’t put at risk.

Damp patch? Spotting the signs

Signs of damp in a property can vary, but here are some common symptoms:

  • A ‘damp’, musty smell
  • Dark or discoloured patches on walls or plaster work
  • Damp patches that spread upwards from the base of the wall
  • Brown or yellow staining or a ‘tide mark’ on the wall
  • Walls or ceilings that feel cold and wet to the touch
  • Peeling wallpaper and/or paintwork
  • Damaged/blistered plaster or skirting boards

How to get rid of damp

If your property is showing any of the signs above , the best advice is to seek help from a damp specialist. You or your trusted handy person may think you know what’s causing the damp, but it’s not always possible to tell how serious the issue might be simply from looking at it.

Ideally you need a qualified surveyor who is a member of The Royal Institution of Chartered Surveyors or The Residential Property Surveyors Association (RPSA). The cure may be as simple as repairing broken guttering and letting the wall dry out, or it may require having a damp proof course renewed. Depending on how easy that is and the damage done to date, this may mean replastering and redecorating. However, it could be more complicated than either of these fixes and sadly, the idea that you can just paint over damp or mould is unlikely to get rid of the problem!

If water has been soaking through walls or flooring for some time, there could be structural damage that’s not visible. And because mould can grow and spread in damp conditions behind wallpaper and tiles, you might not even know it’s there.

So, for any damp-related issues, contact a damp specialist. Make sure they are suitably qualified company, ideally a member of RICS or the RPSA and for anyone that carries out remedial work, they should be a member of the Property Care Association.

How to prevent damp in rented property

If damp problems are left unchecked, it could cost you dearly as a landlord, both in terms of property damage, adverse effects on your tenants’ health and fines by the local authority if you don’t get it fixed.

However, the best cure is prevention, and there are a number of ways you can help avoid damp creeping into your rental property.

  • Make sure any damp proof course is still within its warranty/guarantee period
  • Make periodical property inspections during every tenancy, or make sure  your managing agent does this on your behalf. Tenants don’t always report small issues, so visiting the property every six  months (possibly 12 if it’s become a long-term tenancy) gives you/your agent the opportunity to identify and then rectify any issues before they escalate
  • Make sure that the property is in a good state of repair by getting the property ready for winter, when it’s most vulnerable to damage by the elements, by checking for common problems that can easily lead to damp:
  • Leaking roofs
  • Blocked guttering
  • Blocked or cracked pipes
  • Evidence of rising damp
  • Ineffective damp coursing
  • Blocked or overflowing drains
  • Make sure the property is well insulated  
  • Ensure the heating system is well maintained and serviced annually
  • Fit extractor fans in areas with high moisture content, such as the bathroom and kitchen
  • In areas that are partially prone to moisture – e.g. a laundry room or where tenants tend to dry clothes – it may be useful to invest in a dehumidifier. Although this is an additional cost, it could help save money in the long run

What is mould?

Mould is a fungus that grows in areas with high humidity and excess moisture, so that’s any part of a property where condensation and damp are present. As well as causing damage to the fabric of the property and furnishings, mould can seriously impact the health of your tenants , so it must be removed as soon as possible.

Where ‘surface mould’ has grown because of condensation, it’s commonly called ‘mildew’. Mildew thrives in humidity, which is why you’ll commonly find it in bathrooms. It’s usually grey in colour and appears dry or powdery. In contrast, mould will burrow underneath the surface, so it can be harder to spot early and much more difficult to get rid of. It’s often raised, can be various different colours and generally looks either fuzzy or slimy.

Preventing mould in the property

As well as educating your tenants on the importance of good property ventilation and making sure that the property has no structural issues that could cause a condensation, damp or mould issue, it is a good idea to also be aware that mould growth can be reduced by:

  • Keeping rooms at a constant temperature
  • Covering saucepans while cooking
  • Wiping away condensation as soon as it appears
  • Ensuring doors in ‘wet areas’ are closed to avoid moisture spread

Landlords who wish to take more significant measures to deal with structural issues could consider:

  • Increasing insulation in the property (such as external wall insulation, internal wall insulation, cavity fill, double glazing)
  • Improving the ventilation in the property (installing fans, encouraging airing the property and opening windows, trickle vents, passive vents)
  • Improving heating in the property (regular maintenance checks on heating appliances, making sure the property is kept at a constant temperature, space heating)

How to remove mould from your property

Because mould stems from condensation and damp issues, if you and your tenants take all reasonable steps to prevent those occurring in the first place, you may be able to avoid mould forming in your property. See advice on preventing condensation and damp.

However, if you do end up with a mould problem, the right course of action will depend on the type of mould and what’s caused it to grow. If you don’t identify the root cause, it’s likely to grow again, causing further issues.

It should be possible to remove mildew or ‘surface mould’ fairly easily, with a specialised mould removal (fungicidal) product. Choose one that has a Health and Safety Executive ‘approval number’ and wear protective clothing and gloves when applying it. Be very careful, as spores can be toxic and disturbing mould can increase the risk of respiratory problems.

Once you’ve removed mildew from walls and ceilings, redecorate with a good quality biocidal paint to help prevent it recurring.

For any mould growth that isn’t very obviously just a minor patch of mildew, you should consult an expert. Mould can spread extensively behind wallpaper and tiles, and in spaces in damp brickwork, so you might only be able to see the tip of the iceberg! You can find a damp control specialist via the Property Care Association, and check if their experts are RICS or RPSA qualified.

Damp and mould: the potential impact on your tenants’ health

If damp and mould aren’t dealt with at an early stage, they can spread and cause dust mite infestations – and it’s these that post the biggest threat to your tenants’ health.

The faecal pellets of dust mites produce allergens and, if these are touched or inhaled, they can result in reactions ranging from coughing, sneezing and skin irritation, to difficulty breathing. According to the World Health Organisation, people who live in damp or mouldy homes are 40% more likely to have asthma.

Damp and mould primarily affect the airways and lungs, but they can also affect the eyes and skin. The respiratory effects of damp and mould can cause serious illness and, in the most severe cases, death, as in the tragic case of Awaab Ishak, who died as a result of a severe respiratory condition due to prolonged exposure to mould in a home with inadequate ventilation.

The presence of damp and mould can also affect tenants’ mental health. This could be due to worries about the health impacts of damp and mould, unpleasant living conditions, and destruction of property and belongings, among other concerns.

More elderly tenants, young children, tenants with existing skin problems and those who already have respiratory problems or a weak immune system are particularly vulnerable.

Bear in mind that if your tenant does suffer from the effects of damp and mould in your property, they may report you to the local authority – which can fine you up to £30,000 without going to court – and may also make a personal injury claim against you.

Your obligations as a landlord

As a landlord it is important that you are up to date with your legal obligations and are aware of the latest property standards set by the Government. Read the Government's guidance ‘Understanding and addressing the health risks of damp and mould in the home’ to make sure you’re on top of condensation, damp and mould in your rental property.

This guidance also heralds two of the Renters (Reform) Bill’s key components, the Housing Ombudsman, which will deal with tenant complaints where the landlord hasn’t taken action, and the Property Portal, where a landlord’s compliance with the Decent Homes Standards and other regulations will be recorded.

For more information on how you can protect your property this winter, visit our winter landlord advice page for helpful tips and guidance on minimising the risk of damage.

For more information on damp, mould and condensation in rental properties,  listen to our podcast which was recorded in 2022 before the tragic death of Awaab Ishak, and includes practical advice from Julie Ford, Adviser at HF Assist and Suzy Hershman, Resolution Department Lead at mydeposits and the Property Redress Scheme.

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