Mould in the attic: common causes
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Mould in the attic is usually caused by excessive humidity over a period of time. When it relative humidity rises above 75% RH creates favourable conditions for microbial fouling. Read more about how to treat and get rid of black and white mould in your attic.
Black mould is a common problem in attics. The mould itself is not always dangerous, but it acts as a clear indicator that the moisture environment is unfavourable - which can pave the way for more harmful mould species. White mould, like black mould, is an umbrella term for mould species, but is characterised by its light colour.
Common species of black mould are:
- stachybotrys
- Aspergillus
- Penicillium
- Fusarium
- Cladosporium
It is therefore wise to inspect the attic at least once a year. If mould growth is detected in time, it is often possible to easily remedy the problem and prevent its recurrence.
How does mould affect the indoor environment?
If black mould is allowed to grow freely, mould spores can spread to the rest of the house via the air. In some cases, this can cause discomfort to people who are sensitive. In other words, mould growth in the attic is not only a structural problem, but can also affect the way the air is perceived in the home.
Common signs of problems:
- Stale odour from the wind which spreads down into the dwelling
- Visible growth on the wooden parts of the attic, e.g. on roof trusses or rafters
- Discolouration on plastic film or insulation
How to remove mould in the attic
Black and white mould can be treated with an agent such as Mould-free, which is applied with a pressurised syringe.
- Spray on the product and let it work as instructed
- Work the surfaces with a brush to remove the mould properly
- Check result with UV lamp - repeat if necessary
However, in some cases, replacement of the infested material should be considered if the mould has penetrated and risks affecting the functioning or life of the building. Consult a professional.
Prevent future mould problems
After you have removed the mould, it is important to prevent its recurrence. Plastering and sealing the attic properly is a good start, but it is rarely enough. In fact, it can a tight wind without active moisture control lead to trapped moisture and significantly worsened conditions.
Installing an attic dehumidifier
To ensure long-term protection, we recommend installing a attic dehumidifier. This keeps the humidity at a safe level all year round - regardless of temperature changes or ventilation conditions. If you've already plastered and sealed your attic, you've done the hardest part - adding a dehumidifier is a simple but crucial step.
Also consider installing the control panel in an easily accessible place downstairs in your home. This way, you can easily monitor its operation and recognise any climate alarms in good time.
