How To Prevent Mould Growth In Building?

Preventing mould growth in buildings starts with controlling the conditions that allow it to grow and develop: identifying and repairing sources of water ingress, maintaining effective ventilation, monitoring humidity, drying wet materials promptly and using dehumidification hire where excess moisture cannot be removed rapidly enough.

The dangers of mould have prominently featured in the news in recent days, and this is a topic that everyone should be more aware of. The thought of being a victim to chronic exposure to black mould should be a concerning one. As energy bills soar and the need to cut back takes hold, businesses could be at greater risk of dampness increasing.

Ineffective moisture control has worrying implications for all of us, including those who work for you, so it’s important to ensure that humidity levels are kept within a range of 40-60%. Failure to do so increases the likelihood of people developing respiratory illnesses, skin dryness and eye irritation, but can also have an impact on your building’s structure and its contents.

Black moulds commonly found in UK buildings are Stachybotrys chartarum, Cladosporium and Alternaria fungi – all of which release specific toxins that are harmful to humans. Health concerns such as mycotoxicosis – effectively, mould poisoning – can cause side effects such as memory loss, rashes, persistent illness, shortness of breath and even death.

The most common way that mould develops is via moisture being present in a building. Thus, the most preventable technique to avoid mould in buildings is through targeted moisture control.

What Causes Mould in Commercial Buildings?

In a commercial or industrial building, damp rarely has a single cause. It is usually a combination of a slow leak behind a ceiling tile, a roof that lets in water during heavy rain, an extract fan that stopped working months ago, cold walls next to warm, busy rooms, or simply too much moisture in the air with nowhere to go.

What is condensation?

One big source of mould is condensation. Condensation is the process whereby water vapour in the atmosphere is returned to its original liquid state. When moisture in this form exists indoors, problems such as dampness and mould growth can occur. Although such conditions are easily treated using dehumidifiers, the problem is not uncommon.

Cleaning alone won’t stop it, because mould spores are always present. The risk is highest in basements, storerooms, changing rooms, plant rooms and warehouses, where the air barely moves and nobody spends long enough to notice the smell.

Construction and refurbishment work adds its own share. Fresh concrete, screed, plaster and paint all release large amounts of water as they dry, which is why mould sometimes appears on a brand-new wall within weeks of handover.

The useful question isn’t just “How do we get rid of this mould?” It’s “Why does this area stay damp enough for mould to grow in the first place?”

Finding that answer helps determine whether the appropriate response is building maintenance, better ventilation, some background heat, dehumidification, or a combination of all of these. If you treat the cause, you won’t be cleaning the same patch every winter.

Use Dehumidification to Control Excess Moisture

Our number one tip is to always keep humidity levels between a range of 40-60%, which is generally regarded as suitable for most applications. A dehumidifier will help you keep the level within these parameters.

Measure humidity before you act

Room RH reading	What it means	Suggested action
Below 40%	Drier than needed	Check equipment is not over-running
40–60%	Target range	Keep monitoring
Consistently above 60%	Mould risk at cold surfaces	Find the source; add dehumidification or ventilation
Visible condensation	Mould conditions already present	Dry the area, then hold RH in range

Simply increasing the indoor temperature will not alleviate the problem long-term, and this is costly and energy intensive.

Using dehumidification can also help accelerate drying times on time-limited construction projects. A desiccant dehumidifier, for instance, is perfect for drying sensitive materials and simultaneously maintaining a stable level of RH which in turn will prevent mould development.

Choose the Right Dehumidification Approach

Not every moisture problem requires the same type of equipment. The right solution depends on the building, temperature, moisture load, required drying rate and how the affected space is being used.

• Building dryers are a practical option for removing excess moisture from buildings during construction, refurbishment, flood recovery and general property drying.
• Refrigerant dehumidifiers are commonly used for general moisture control in enclosed commercial spaces operating at moderate temperatures.
• Desiccant dehumidifiers are particularly effective in colder or unheated environments and where lower or more tightly controlled relative humidity is required.

Not sure which option is right? See our guide on how to choose the right dehumidifier or our advice on speeding up drying times on construction projects so mould doesn’t appear after handover.

Keep your building properly ventilated

Don’t forget ventilation; a fan used on extraction mode will ensure the damp air in your building is transported outside. Many buildings lack a built-in exhaust or extractor fan, or have inadequate ventilation, but we can solve this issue with minimal fuss. We even offer customers the option of purchasing ventilation solutions for sale, enabling you to instil a pleasant working environment with fresh air constantly circulated.

Ventilation and Dehumidification Work Differently

Ventilation and dehumidification address moisture in different ways. Temporary ventilation hire introduces fresh air and removes stale or humid air, while a dehumidifier actively removes water from the air inside the controlled space.

Depending on the building and the weather outside, one method may be enough. Where the requirement is more complex, a combination of both usually works best.

Preventing mould through heating

Whilst many are tempted to save on heating costs this winter, one of the best mould prevention techniques is keeping the heating on – particularly when used in combination with drying, ventilation, or both. Experts suggest that the ideal room temperature is between 20-23°C as far as preventing dampness is concerned, and this can easily be achieved with our help.

Why Heating Alone May Not Solve the Problem

Heating hire can reduce the likelihood of condensation by increasing surface and air temperatures, but it does not remove the moisture itself.

This distinction matters in commercial buildings. Continuously adding heat to a moisture-heavy space without sufficient ventilation or dehumidification may improve conditions temporarily without resolving the underlying humidity problem.

For difficult sites, a more effective temporary moisture-control strategy may combine:

controlled heating + air movement + dehumidification

There are some quick fixes that can prevent or slow down mould growth, including keeping traditionally damp areas dry, regularly cleaning, and addressing any plumbing leaks or pipework issues as soon as they are detected.

After a leak or flood, begin drying as quickly as possible using appropriate water damage drying equipment.

However, to ensure a long-term fix, installing or hiring a purpose-built dehumidification heating or ventilation system can help eliminate mould growth and ultimately enhance your premises from a health and safety standpoint.

In listed buildings and museums, stable humidity matters more than heat; see our guide to tackling damp in older buildings.

Whether you are concerned about the health risk of mould in your facility, or the effect it can have on the building itself, it is important to remove mould as quickly as possible and take action to prevent it coming back.

Need Help Choosing The Right Drying Solution?

Our specialists can visit your site for a free survey. They’ll take humidity readings, find the source of the moisture, and recommend the right mix of dehumidification, heating and ventilation for the space. Equipment can be deployed the same day, with our team support available 24/7, 365 days a year.

If you’re reading this blog, you’re already in the right place! So, call us today on 0800 211 611 or complete an enquiry form, here.