Understanding and Tackling Mould in Rented Homes: A Guide for Tenants

Mould and damp issues can be frustrating for tenants, especially when they’re caused by condensation. As winter approaches and the temperature drops, condensation—and subsequently mould—becomes a common concern in many households. Understanding the causes and taking preventative measures can make a significant difference in protecting both your health and your home.

In this article, we’ll explore how to identify mould caused by condensation, understand why it happens, and provide tips on how to manage it. We’ll also highlight relevant clauses in your Assured Shorthold Tenancy (AST) agreement, including those that outline your responsibilities around cleaning and ventilation.

Identifying Mould Caused by Condensation

Condensation is a leading cause of damp and mould in homes, especially in colder months. Unlike penetrating or rising damp, condensation-related damp is typically surface-level and can often be seen on walls, windows, and other surfaces where warm, moist air meets a cold surface.

Here’s how to tell if you’re dealing with condensation-based mould:

1. Location: Condensation damp usually appears on or near windows, external walls, and in areas with poor ventilation like bathrooms and kitchens.
2. Appearance: Mould from condensation is often black or greenish in colour and tends to look patchy/spotty, spreading out in clusters on walls, ceilings, or around windows.
3. Accompanying Signs: If you notice persistent fogging on your windows, damp spots on your walls, or water pooling on surfaces, it’s likely caused by condensation.

Why Does Condensation Happen?

Condensation forms when warm, humid air comes into contact with cooler surfaces. As the air cools down, it loses the ability to hold moisture, which then collects on these surfaces. Here are common reasons this happens in rented properties:

• Poor Ventilation: When there’s insufficient airflow, moisture in the air has nowhere to escape, leading to condensation.
• High Humidity Activities: Everyday activities like cooking, showering, and drying clothes indoors without proper ventilation can add moisture to the air.
• Cooler Indoor Temperatures: If a property isn’t kept warm enough, the temperature difference between warm air and cold surfaces increases, making condensation more likely.

Tips for Preventing Condensation and Mould Growth

Taking a proactive approach to prevent condensation can save you from dealing with mould growth down the line. Here are practical steps to help reduce moisture build-up in your home:

1. Ventilate the Property Regularly
   • Ensure your home is well-ventilated by opening windows (especially in the kitchen and bathroom) and using extractor fans where possible. This is particularly important after cooking, showering, or drying clothes indoors. Many AST agreements, stipulate that tenants must “take all appropriate precautions to ensure adequate ventilation.”
2. Heat Rooms Consistently
   • Keeping a steady, mild temperature can help reduce condensation. Try to avoid letting rooms get too cold, as this will encourage moisture to settle on cold surfaces. Even a low level of background heating can make a difference in colder months. While this can be a challenge when it comes to cost, it is an important step to present mould growth.
3. Avoid Drying Clothes Indoors
   • If possible, try to dry clothes outdoors or use a dryer with proper ventilation. If you need to dry clothes indoors, try placing them in a well-ventilated area and using a dehumidifier to absorb extra moisture such as a bathroom with closed door with the extractor fan on.
4. Clean and Maintain Windows
   • Many ASTs requires tenants to keep the windows clean. This is essential, as water droplets that are left, will make window frames wet and bread mould. Dirt and grime can trap moisture, making condensation more likely to form on windows. Regularly wiping down windows and their frames can help minimise condensation and mould.
5. Use Dehumidifiers
   • Dehumidifiers can help reduce the amount of moisture in the air, especially in areas that tend to stay damp. Portable, affordable dehumidifiers are widely available and can be a worthwhile investment for rooms that experience frequent condensation. Avoid the cheap disposable kinds and instead opt for an electronic appliance.
6. Clean Mould Promptly
   • If you notice mould beginning to develop, clean it off as soon as possible. AST agreements require tenants to clean items that have become soiled. Use an appropriate anti-mould cleaner, and wear gloves and a mask to avoid exposure. Addressing the mould early will help prevent it from spreading further.

What to Do if Mould Persists

If you’ve followed these preventative steps but continue to experience mould problems, it may indicate a structural issue such as poor insulation, inadequate ventilation systems, or other building-related problems. In such cases, notify your landlord or property manager in writing. They are responsible for ensuring the property is fit for habitation, including addressing significant issues that contribute to damp and mould.

Your responsibility as a tenant is generally limited to maintaining reasonable ventilation and cleanliness, as stated in the AST clauses 8.2.8–8.2.10. Beyond that, it’s the landlord’s duty to tackle structural issues.

Summary Checklist: Preventing Mould Caused by Condensation

• Ensure regular ventilation, especially in high-humidity areas.
• Keep a consistent mild temperature throughout the home.
• Avoid indoor drying of clothes or use a dehumidifier.
• Clean windows and frames to prevent moisture buildup.
• Use a dehumidifier in persistently damp rooms.
• Report ongoing issues to your landlord if mould persists despite following these steps.

Final Thoughts

Dealing with mould caused by condensation is a common challenge for tenants, but taking preventative steps can make a big difference. By understanding what causes condensation and taking proactive measures, you can help keep your living environment healthier and more comfortable. Remember, check your AST for specific clauses