How to Deter Mould Growth in Your Cool room

The discovery of mould in your coolroom can strike fear in any business owner. Most coolrooms are used to store food, and obviously, food and mould don’t mix. Even if your coolroom is used to store non-food items like flowers, cosmetics, or technology, eliminating and preventing mould needs to be a top priority. 

Mould has a detrimental effect on all kinds of goods, and if health inspectors find mould in your coolroom you risk being closed down and suffering damage to your company’s reputation. How can we deter mould from growing in the first place? As experts in commercial refrigeration in Perth, the team at All field have a few recommendations you can implement for your coolroom. 

Why does mould grow in coolrooms? 

Before we can start talking about how to prevent mould, it’s important we understand why mould can start to form in coolrooms in the first place. 


Invariably, mould grows because there is moisture present—without moisture, mould cannot grow. While impossible to completely irradicate all moisture in a cool room, a coolroom that is functioning and operated as should not have enough moisture present to allow mould growth. 

Moisture in a coolroom can take the form of dampness, condensation, and humidity. A common cause of high moisture within a coolroom is broken or poorly maintained components of the room. Coolrooms that are not working optimally can allow excess moisture to develop and will lead to mould growth if the conditions are right. 


Mould cannot grow if the temperature within a coolroom is not within a particular range that allows mould growth. Most common moulds cannot grow if the temperature is below 4°C, so you should always ensure your coolroom is below this temperature (if possible for your goods). 


Mould thrives in dark conditions. This is because UV light—present in sunlight—destroys mould. Coolrooms obviously rarely receive sunlight because they are windowless rooms that only briefly receive natural light when the door is open. 

How can I deter mould growth in my coolroom? 

Deterring mould growth in a coolroom involves mitigating the causes of mould growth mentioned above—moisture, warmer temperatures, and darkness. 

#1 Ensure all sealing is in order  

Condensation forms in a cool room whenever warm air enters the room—the warm air mixing with the cold air in the coolroom causes condensation to form on the walls and the goods in the coolroom. Warm air can find its way into your coolroom if the sealing around the door is cracked or damaged. 

Coolroom door seals need to be replaced periodically—usually every few years. If you notice the sealing around your coolroom door is cracked or otherwise damaged, it’s crucial you get it sorted out immediately. 

#2 Keep time the door is open to a minimum 

As mentioned, condensation forms due to warm air entering the coolroom. This will occur whenever the coolroom door is open. Of course, the door needs to be open sometimes—usually multiple times throughout the day as goods are moved in and out of the coolroom. However, the duration that the door is open should be kept to an absolute minimum to limit the amount of warm air that enters. 

Never leave the door ajar during deliveries or as goods are being moved—close it after entering or exiting every time. If prolonged work must be done inside the coolroom, the door should still be closed—coolrooms can be opened from the inside. 

If a person is concerned about becoming trapped inside a coolroom, they should first check the internal opening mechanism is functioning as it should with another staff member outside the coolroom. Another staff member should set a twenty-minute alarm so they are reminded to check on the person working in the coolroom, and appropriate PPE (thermal clothing) should be worn when staff are working in the coolroom. 

#3 Check for damage to the walls, ceiling, and floor 

Coolrooms with good build quality are generally very durable, but damage to a coolroom should be routinely checked for. Perforations to the insulated panel walls are the most common type of damage. If a vacuum-sealed panel is punctured, it will no longer function as intended and could lead to increased moisture and warmth in the coolroom. Check around the entire coolroom interior for scratches, dents, and perforations, and repair any damage you find as soon as possible. 

#4 Immediately clean spills 

The presence of food and drink spills in the coolroom can facilitate the development of mould. Any spills should be cleaned immediately after they occur or are spotted. Also, routinely move stock around in the coolroom so that no spills go undiscovered.  

#5 Stay away from wooden shelving 

Wood is porous and it will absorb spills, condensation, and general moisture. Wooden shelving can create the perfect environment for mould growth. Metal shelves are far superior to wood shelves when it comes to deterring mould since it’s very difficult for mould to grow on a non-porous surface, and spills can be easily cleaned. 

#6 Clean the coolroom regularly 

Regular cleaning will help to kill any mould that begins to develop in your coolroom. Especially important is to clean the seals around the door. Your business should have a routine cleaning process in place. All coolrooms should be thoroughly cleaned at least once a week, and you may choose to clean your coolroom more often than this. 

#7 Use a UV light 

As we discussed earlier, mould thrives in dark conditions—which is unfortunately the exact conditions of a coolroom. UV light destroys mould and bacteria and so the installation of a specialist coolroom UV light is a viable way of deterring mould growth. 

#8 Check the temperature 

Common moulds are unable to grow when temperatures are below 4°C and therefore, in almost all circumstances, coolrooms should be set to temperatures below this. Read the built-in thermometer of the coolroom, but also periodically compare this to a portable thermometer so you can ensure your coolroom thermometer is functioning correctly. If it isn’t, the temperature of your coolroom could be higher than you think it is. 

Does your business also require commercial air conditioning in Perth? Find out more about our design and construction services for commercial air conditioning. 

#9 Routinely look for mould 

Mould can develop quickly, and once it does, the spores can end up contaminating other surfaces and even the air in the coolroom. Checking for mould routinely will prevent the spread of mould. The whole coolroom should be checked over for signs of mould, but some areas are more vulnerable to mould growth. 

Areas vulnerable to mould include the seals around the door—here, the temperature may be higher than the rest of the coolroom and the rubber material is more conducive to mould growth. Concrete can develop mould, so the walls of coolrooms that use concrete should be checked routinely. Paper in a coolroom can become a breeding ground for mould, so the presence of paper packaging should be kept to a minimum. Also, ensure expired food and other goods are discarded straight away—mould particularly thrives on food. 

#10 Clean and service the refrigeration systems 

Along with regular cleaning of the coolroom itself, the refrigeration systems—such as the condensing unit, evaporator, and compressor—need to be regularly cleaned and serviced. If mould is present in these systems, mould spores can quickly become airborne and contaminate the entire room. 

Additionally, if the refrigeration systems are not functioning correctly, the coolroom can suffer from poor ventilation which is a leading cause of condensation, potentially resulting in mould growth. Cleaning and servicing the refrigeration systems are best left to professionals like us at Allfield otherwise you risk damage to the systems as well as leaving mould behind.  

Learn how to detect common indications your coolroom needs repairs. 

What if my coolroom already has mould? 

In the case that you discover mould has developed in your coolroom, immediate action is necessary. The presence of mould generally means there is a problem with a coolroom, and you should arrange a service with a reputable refrigeration services team like Allfield. This will mean you can identify the problem in your coolroom so that mould doesn’t continue to grow. 

After you have arranged your service, it’s time to eliminate the mould. To do so, a deep and thorough cleaning is in order that will remove all mould and mould spores. First, remove all goods and check them for mould. You may need to waste these items. Then, clean every single surface within the coolroom—floor, walls, ceiling, and shelves. Use a vacuum to remove debris and particles. You’ll want to use a suitable chemical solution that states it can be used to kill mould and bacteria in combination with an abrasive scrubber.  


Never get complacent about mould in your coolroom. As soon as you spot it, sort it. Even better is to actively deter mould growth so that you never have to deal with mould in your coolroom. Following the above advice will go a long way in preventing in killing mould in your coolroom. The best thing you can do for your coolroom is regularly maintaining and service it through a reputable refrigeration services team such as Allfield Refrigeration & Mechanical Services

Speak to Allfield today to arrange for coolroom servicing, upgrading, and commercial refrigeration repairs Perth. 

1800 265 337