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How Do I Prevent Black Mould?

As a property developer, Stella has written many articles on the home environment, decor and problems that arise in the home and garden.

Where Does All That Steam Go? It Settles on Cooler Surfaces, Causing Black Mould to Grow

Ventilation is the key to combating condensation and black mould caused by water vapour in the home

Ventilation is the key to combating condensation and black mould caused by water vapour in the home

Condensation and Black Mould are Lifestyle Issues

In October, in northern climates, your home may be affected by condensation issues which will continue for six months until the weather grows warm again. This often seems to be an insurmountable problem but the solution is fairly easy to implement, Home-owners and tenants alike can rid their homes of mould and mildew by taking just a few steps to ensure excess water vapour can freely escape from the property.

Air bricks and ventilation grilles placed on the inside of exterior walls and internal chimney breasts etc are there for a reason - to ventilate your home but often during the winter months, householders decide to block them up with boards and rags etc. They do this to keep the heat in but they're also trapping in moisture. Homes can become so tightly sealed against the weather, that people don't realise the moisture generated inside the home now has nowhere to go. The occupants' safety can even be at stake if ventilation grilles installed for gas appliances are also blocked up. They are there for a reason - to protect you from carbon monoxide poisoning.

Ventilation, Ventilation, Ventilation! This is the Answer to Black Mould Prevention

Inadequate ventilation is the primary cause of condensation on windows and the mould growth commonly associated with it over the winter months. Moisture build up in the home needs to escape or you will find nasty things occurring such as peeling wallpaper, mould growth on natural fabrics and in areas where there is little air movement such as in corners of rooms or behind wardrobes.

Moisture build-up and mould growth can cause significant internal problems to the fabric of the building and contents and even poses a significant risk to health if mould is left to grow unchecked. Don’t complain to your landlord about a mould problem when it's a lifestyle problem caused by yourself! Mould will only grow when conditions are moist. Banish excess moisture and the mould will go away. Getting rid of condensation and the black mould it produces is a problem you can easily tackle by reducing the moisture content in the air and allowing adequate ventilation.

Existing mould can easily be eradicated with a bottle of spray on mould and mildew killer available very cheaply from just about any supermarket.

Home occupiers often make the mistake of thinking their home has serious building defects, not realising it is internal moisture build up that causes condensation and mould to occur. Condensation is never caused by ingress of water from the outside. In fact, black mould hates outside water as it will have come through the brickwork and be too salty!

Before the onset of winter, it's always wise to check the fabric of the building so gutters, roofs and damp courses continue to protect your home from outside conditions. When these are fully functional, it further proves that your mould and condensation issues are an internal problem. You can also have all internal pipe work checked to ensure the pipes are water tight too. Water stains from internal leaks leave an orangey brown tinge and again are not associated with condensation and black mould growth.

From October to March, you'll likely see condensation developing on your windows especially first thing in the morning. Even breathing causes the moisture in the air to condense on the internal window panes and if you never open your windows over the winter for fear of losing precious heat, the problem will only get worse. The more occupants and pets you have in your property, the more severe the condensation will be. Whereas nothing can be done about breathing there are steps you can take to reduce build up of moisture from other sources.

Installing a dehumidifier can help immensely, as can using extractors in kitchens during cooking and in bathrooms when taking a bath or shower.

Cut down on the moisture content in the air by installing a vent for your tumble drier if it is not the self-condensing type and installing vents and air bricks so your home is not hermetically sealed allowing little excess moisture to escape.

Some definite no-nos are drying washing indoors, bathing with the bathroom door open and blocking up air vents - where do you think all that moisture goes? It won't just disappear; it will condense on your windows or a cold wall or surface and cause internal damage to décor and possessions often in a place far removed from the initial source of the moisture. This is the most confusing aspect as you would never think ironing in a downstairs room could cause mould growth in an upstairs bedroom. But it quite easily can.

Keep your background heating on low all winter. Constantly turning the heating on and off over the winter months will cost you more and is uneconomical. Every time your heating system has to start up from cold it uses far more energy than maintaining it at a constant level. Maintaining an even temperature throughout the building and providing adequate ventilation ensures that condensation problems will be kept to a minimum.

Fresh air is needed to maintain a healthy environment in the home so don’t ‘batten down the hatches’ all winter for fear of incurring costly fuel bills. Ventilating your home correctly and allowing excess moisture to escape will not only keep condensation on windows at bay but will save you money on costly repairs and redecoration. Windows should never be opened on days when the weather outside is clearly more damp than it is inside, but on a bright, clear winter's day with a brisk breeze blowing, that's the ideal time to ventilate. Just a few minutes each day should be sufficient.

Black Mould Removal - Advice for Tenants

If you find black mould in your home contact your landlord for advice by all means but don't be quick blame the fabric of the building. He's likely to have encountered the problem before and will be willing to advise you how to tackle it effectively. He may issue you with a fact sheet. Don't assume that there's a problem with the property and don't be offended when you're told it's caused by something you're doing.

Condensation and black mould issues are a huge bone of contention between landlords and tenants but they can so easily be remedied with the correct communication between you and your landlord. Never paint over black mould; this is the worst possible thing you can do as it will come back with a vengeance.

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The wall in the photo below was cleaned by me and the mould never returned. It was caused by a tenant never opening the bathroom window every time she took a shower. She never attempted to clean it with some readily available mould killer and so it built up to the point where the whole house became covered in mould and was uninhabitable. She never opened the windows and whenever I passed the property, I could see condensation streaming down them. She never put any heating on all winter which made the situation even worse. It clearly demonstrates how a minor problem can get out of hand if not addressed swiftly and in the proper manner.

A Bad Case Of Black Mould Caused By Condensation


Black Mould Always Occurs In Corners Where There's Little Air Movement


How To Deal With Black Mould And Condensation Issues

Further Information On Activities That Encourage Black Mould Growth

© 2015 Stella Kaye


George Carr from Corpus Christi, Texas on December 30, 2019:

Excellent educational article on black mold. The article also provided a few energy saving tips. It should be mandatory reading for every first time home owner and every new apartment dweller.

Not only is black mold aesthetically ugly, what mold does to the lungs is almost criminal.

'Nuff said, I am going open some windows for ventilation.

George Carr

Mary Wickison from USA on July 19, 2017:

Although we have high humidity, our temperature is warm. We are able to ventilate the house and have windows open year round. That said we still have to be vigilant about mold on our sofas, and even our outside pathway, especially during our wet season.

Even our books begin to rot away! I try and keep air circulating by leaving a wide gap behind furniture. Prevention is better than the cure.

A closed up house with fungus and mold can also be unhealthy due to the spores. Although no one likes a draughty house, having a source of fresh air, is beneficial.

Stella Kaye (author) from UK on October 06, 2015:

Thank you for reading my article, I'm pleased you found it useful.

RTalloni on October 06, 2015:

Some good food for thought here. SC has been in the news due to flooding, but the entire East Coast has developed a high humidity situation. Many are thinking through how to reduce indoor humidity right now and you offer some useful tips.

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