Mould is a perennial problem for landlords and homeowners in the UK. The damp climate and elderly housing stock of this island combine to create the perfect conditions for a build-up of excess moisture within properties. Unless steps are taken to improve ventilation in homes where condensation is a problem, damp and mould are the nearly inevitable consequences. Damp can be a serious issue in its own right—potentially causing structural damage—but from a health and wellbeing perspective, mould is the greater concern.
Many types of mould can form in a property, and many of them are harmless (although unsightly). However, ten common varieties of mould can cause health problems, and one of the most common of these—black mould, known to science as Stachybotrys chartarum—is also one of the most harmful.
Exposure to mould spores or fragments can could inflammation in the airways, congestion, tightness in the chest, coughing, wheezing, soreness, rashes and watering eyes. More seriously still, there is a strong link between mould-exposure and childhood asthma, according to the World Health Organisation.
The toxic spores of black mould have been shown to cause serious respiratory illness is vulnerable people. In 1994, ten children in the UK suffered bleeding in the lungs as a result of a single black mould outbreak, resulting in one death.
Children and babies are especially vulnerable to the effects of mould-exposure, but so are many other people, including the elderly, anyone with eczema or other skin problems, those with existing respiratory issues such as asthma, and people whose immune systems are weakened.
As soon as a mould outbreak is identified, it should be treated, but this comes with costs. Small outbreaks can be dealt with by residents or non-specialists, but NHS Choices suggest that this should only be attempted with mould caused by condensation, covering an area no greater than one square metre (three square feet). Mould outbreaks caused by rising damp or potentially contaminated water—or where the cause cannot be identified—should be tackled by a professional, as should outbreaks covering an area greater than a square metre. That means that, at a minimum, a large outbreak or an outbreak of unknown cause will entail the cost of hiring an expert. Further costs can rack up quickly: paint, wallpaper and furnishings may be stained or damaged, and in the case of serious outbreaks, it may be necessary for residents to spend a night or more in a hotel.
Where costs such as these have been incurred, your home insurance may pay out to cover them. It depends on your policy, the cause of the mould outbreak, and whether you as the property owners take reasonable steps to prevent the outbreak occurring.
The first issue your insurer will consider is the cause of your mould outbreak. Identifying the cause is also important in deciding how to tackle an outbreak.
A build-up of condensation causes most mould. Condensation occurs when moisture in the air—released by cooking, cleaning, laundry, or just breathing, or else introduced from outside— has nowhere to go. When warm moisture-laden air comes into contact with a cool surface, it forms droplets of water, and it’s in these conditions that mould thrives.
Condensation is often found on the interior of windows (as windows tend to be colder than the interior air of a property). Double-glazing can address this issue, but be aware that a double-glazed window provides no ventilation, which can itself contribute to the build-up of excess moisture inside your property.
Less familiar, but also common, is interstitial condensation, which occurs when moisture-dense air is able to penetrate a hollow space inside a wall, roof or floor. These cavities are likely to be at dew-point temperature, causing moisture from the warm air to condense. Interstitial condensation often underlies severe mould outbreaks, because the outbreak begins within the wall, where it is not visible. If you suspect you may have interstitial condensation in your property, you should act immediately: you may already be exposed to significant levels of mould spores.
Mould can also spring up where there are other sources of excess moisture, and these are potentially the most dangerous cases of all. Where mould might be caused by contaminated water—from a sewer pipe, for instance—immediately contact a professional.
When you first discover a mould colony, do not touch it or disturb it in any way. Contacting the mould is likely to release spores into the air, as well as fragments of the mould itself, which can also be harmful.
Second, identify the cause of the mould. If the primary cause is condensation, and the outbreak covers less than a square metre, you can attempt to remove it yourself. Otherwise, contact a professional.
Wear rubber gloves, goggles and a face mask to tackle a mould outbreak. Open any windows in the room, to help clear spores, but close doors, so that spores do not spread through the house.
You can buy specialised mould-removal products in most supermarkets. A mixture of one part bleach to four parts water will also do the trick—although be careful to prevent the bleach from contacting anything which might be stained by it.
Use a damp cloth to wipe away the mould. Afterwards, dry the affected area thoroughly, to discourage the mould from returning. Wrap all the cleaning materials you have used in plastic and throw them away when you have finished.
Bear in mind that if your mould problem is caused by condensation, it will almost certainly return, unless ventilation in your property is improved, ideally with the installation of a mechanical ventilation system.
If you have mould in multiple rooms, a large outbreak, or an outbreak of unknown cause, seek professional advice immediately.
Providing that your home and building insurance is up-to-date and paid for, and your policy protects you against mould outbreaks, you will be covered. However, few policies offer universal protection against mould, and a great many will not pay out for mould outbreaks caused by a preventable build-up of condensation—which is the cause of most outbreaks.
First and foremost, your insurer will want to determine the cause of the mould outbreak. Where the cause is unforeseeable damage, like a burst pipe, the chances are that you will be covered for the outbreak, as you would be covered for other damage caused by the leak.
However, where the cause is a “maintenance” issue, your insurer may refuse to pay your costs. Most condensation issues are regarded as maintenance issues since they tend to occur when a property or its contents are maintained at a sub-optimal level: for instance, when a showerhead is leaky or an extractor fan clogged or broken. If your property simply has insufficient ventilation, that too is likely to be regarded as maintenance issue by most insurers. In these cases, you may still be covered, but you should check the small print of your policy.
When purchasing home insurance, look out for specific mentions of mould: some policies have a clause specifically excluding mould from their scope. Although most policies will not offer universal cover against mould, most insurers will offer a mould-insurance clause as an optional extra (for a fee, of course).
All-in-all, prevention is the safest way to save the cost of mould removal. In the event of an outbreak, mechanical ventilation is more likely to pay for itself than your insurance premiums.
Rather than wait for an outbreak and hope that your insurer will pay for the costs, it’s best to tackle the problem of mould at its source. In most cases, this means tackling condensation.
Ultimately the only way to prevent the build-up of moisture in your property is to improve ventilation. You could open your windows more, although this has obvious downsides, especially on wet days. Extractor fan in moisture hotspots like the kitchen and bathroom help, as does making sure that bathroom and kitchen doors are kept closed when those rooms are in use.
The best solution—and the only one guaranteed to prevent serious mould outbreaks—is a properly-installed mechanical ventilation system.
Positive Input Ventilation (PIV) is an extremely cost-effective way to ventilate your home and prevent the build-up of condensation that leads to mould outbreaks. PIVs draw air from outside your home through a filter to a central unit, which then distributes that air throughout the property. Simultaneously, internal air is drawn out, moisture and all, and expelled into the air.
If you own a property which is afflicted by mould, installing an EnviroVent PIV unit may be a great money-saving solution for you. Contact us to discuss your damp problem and request a quote for a permanent solution.
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