Mould Growth

While generally an all year round problem, mould growth can become more of a problem towards the autumn and winter months so now is the best time to start prevention measures. Before we get into those, it’s important to know the science bit about how it grows and what exactly mould is. Mould is a type of fungi that occurs completely naturally in nature and its main function is to help with the decomposition of organic matter such as leaves. Going by that definition, it obviously has no use indoors. They reproduce through spores that float around in the air and only grow into visible colonies when they spend enough time on a suitable surface containing moisture and nutrients.

Materials that are used in the building of most homes like plywood and carpets are fantastic for mould to take hold of so the key to prevention is moisture. Excess moisture appears after flooding, plumbing leaks, buildings that are too airtight so moisture can’t escape, not enough ventilation near ovens and showers resulting in condensation and general high humidity levels. Condensation also occurs when air gets colder and it loses its ability to retain moisture.

The most common one out of those for Irish homes is probably condensation. It’s an internal problem arising from moisture that can’t escape. To prevent condensation and in turn contribute largely to the prevention of mould you should:

• Have a good ventilation system in place – extractor fans in bathrooms, exhaust fans in cooking and laundering areas and open windows 
• Dry windows and windowsills when you notice condensation forming 
• Insulate cold surfaces well in order to keep central heating low to stop build up on windows, walls and floors 
• Try to keep carpets and rugs away from water sources like sinks and showers 
• Dry washed clothes outside as much as possible 
• Air cupboards and wardrobes frequently 

If mould is already a problem in the home, the best thing to do is get rid of what’s already there and then take preventative measures. Mould killing sprays can be bought in most local supermarkets and these are effective in removing small growths, although a mixture of water and bleach can also help. If on walls or skirting boards, fungicidal paint can be used after the clean up to prevent a recurrence of the problem. For larger growths it is recommended to call a professional mould remover. Certain materials like insulation and carpets can’t just be treated, they need to be removed and replaced.

If you spot the beginnings of mould growth (black pinpricks) take action immediately. While not generally toxic, mould can be an irritant and can contribute to respiratory problems.

*Information sourced from the CDC, the Canadian Centre for Occupational Health & Safety, A Guide to Dealing with Mould and Condensation produced by Stockport Homes (it has some interesting illustrations showing how much excess moisture can be produced by ordinary activities), Dover District Council and general knowledge remembered from years of studying home economics and biology!