Condensation & Mould – How can it be Treated? (Part 2)

Condensation & Mould – How can it be Treated? (Part 2)


As covered in part 1, damp and mould in domestic properties can lead to health issues. There are simple steps that both tenants and landlords can take to prevent damp and mould. Everyone living in the property, needs to have a basic understanding how daily routines can contribute to damp and mould around the house and what needs to be done (or more often not done) to prevent issues arising.


Below are some of the common issues that cause condensation and can often be ascribed to “tenant behaviour”:

  • Hanging wet clothes on radiators increases the moisture in the air which then flows around the house, collecting on cold surfaces and contributing to the growth of mould. To avoid this, dry clothes using a tumble dryer if provided, on a portable heated plug-in airer with a cover or on any airer in a well-ventilated space with an open window or dehumidifier to draw moisture out from the air.
  • Poor air circulation; there must be some air flow around the property whatever the weather – The average person breathes out approximately two litres of water every twenty four hours and an average family of four will generate nearly fourteen litres of water a day during cooking, washing, drying clothes and bathing! Historically this vapour would have naturally escaped, however heat loss and money saving measures such as double glazing and insulation now trap that moisture inside the property. External windows and trickle vents (these should to be regularly checked for good operation) need to be opened regularly to allow fresh air to circulate. Without opening windows moisture builds up and creates mould on cold surfaces such as walls. If furniture is placed directly against walls or radiators, or if cupboards or wardrobes are solidly packed with possessions air is prevented from circulating, contributing to damp conditions.
  • Failing to keep the property at an ambient temperature; having heating on regularly, even at a low temperature, helps to prevent damp and mould. Referring to dampness and mould, the World Health Organisation (WHO) Guidelines for Indoor Air Quality recommend keeping rooms between 18c – 20c. It is a well known fact that if a property fluctuates between hot and cold, this temperature variation will encourage condensation and if left unchecked lead to mould.
  • Running a hot shower or bath, creates steam and additional moisture in the air which circulates and collects on cold surfaces around the house. Running an extractor fan on, where provided, during the time of use and in the case of showers leaving it to run for a few minutes longer after finishing, helps to create a vacuum effect and remove excess moisture. This is pulled out of the air into the fan and released outside through vents or pipes.
  • Cooking, especially boiling water for vegetables, creates steam and additional moisture, which needs to be removed. When boiling water it is advised that the lids remain on the saucepans to prevent excessive loss.
  • Condensation or surface dampness that collects on windows or walls, should be wiped with a clean cloth or towel daily. This will minimise the subsequent appearance of any black mould.
  • In areas of increased water usage such as bathrooms and kitchens it is quite common for mould spots to appear around windows. There are many times where a previously unknown defect in the building becomes evident and once reported, the Landlord can then undertake a repair or replacement.


If there is evidence of a plumbing leak or water ingress from a damaged roof, chimney or guttering which is causing water to penetrate the property or repeatedly flow against walls, then immediate action needs to be taken to minimize the damage to the property.


A dehumidifier can often help if excess moisture is visible – this pulls moisture from the air, reducing vapour and is essential in a property where there is a known mould problem or where excess condensation is being created. Portable dehumidifiers are widely available at different prices through online and high street retailers and most cost very little to run. It is worth noting that the container that collects the water needs to be emptied regularly and obvious areas of water such as toilet pans need the covers down and the doors shut to avoid unnecessary water being collected.


Several groups of houseplants have characteristics that help to reduce humidity levels including the peace lily, ferns, orchids, palms and spider plants.


While waiting for the repair, limit any internal impact by drying surfaces and collecting leaks in a bucket or other container. Occupiers should dry any wet surfaces regularly and treat signs of mould either with mould and mildew cleaning products which are widely available from supermarkets and household retailers. For those more planet friendly users; a white vinegar based DIY treatment can be used. It is advisable to wear a face mask to prevent the inhalation of spores, taking care to ventilate the room and protect the skin.


The key to preventing condensation and mould is for the landlord to be proactive and look at the property (Before the tenancy starts) through the tenants` eyes as to how it will be used. Having “risk assessed” the usage, several steps can often be put into place to minimize the impact and any damage that might inadvertently be caused by just living there!


Landlords should include a helpful Fact Sheet out to new tenants, as part of a pack, and then explain the potential areas of concern and what they should do to avoid having a mould problem. By taking this simple action, many of these common condensation issues would not occur or at least only to a manageable degree. If tenants have a clearer understanding of what their actions might cause, the chances are that they will take more care in their day to day living.


Similarly, talking to the tenant both at the beginning and throughout the tenancy can help to a better understanding of potential issues and enable a quick reporting procedure to be set up if something does happen. Many tenants have no rapport or trust with their landlord and feel unable/unwilling to talk to them, so issues, especially mould, go unreported and over time become worse and a lot more costly to fix!


The answer to this problematic issue for landlords is quite simple – they need to risk assess the property, be proactive to any issues, visit the property on a regular basis and communicate with the tenant/s.