What Temperature Should a Coldroom Be?

Getting the temperature right in a coldroom is not just about food quality. It is a legal requirement for most commercial operations. Whether you are storing fresh produce, chilled meat, or frozen goods, the correct temperature range depends entirely on what is inside. But knowing the target is only half the battle. A room that cannot hold that temperature is just as much of a problem, and the causes are often hiding in plain sight.

How a Coldroom Actually Works: Removing Heat, Not Adding Cold

A common misconception, even among people who work with coldrooms regularly, is that a refrigeration system makes a room cold. It does not. What it actually does is remove heat from inside the room and transfer it to the outside environment.

Refrigerant circulates through the system, absorbing heat from the air inside the room as it evaporates in the evaporator coil, then releasing that heat outside as it condenses in the condenser unit. The room does not get cold. The heat gets moved.

This distinction matters practically for a few reasons:

• It explains why insulation is so critical. The refrigeration unit is constantly working against heat trying to get back in through the walls, floor, ceiling, and door. The better the insulation, the less heat ingress, and the less work the unit has to do. A room with degraded panels or a poorly sealing door is not just a bit leaky. It is actively undermining the refrigeration cycle.
• It explains why product load matters. Every warm item you put into a coldroom brings heat with it. The refrigeration unit then has to remove that heat before the room returns to its set point. A heavily loaded room with frequent restocking demands significantly more from the unit than the room volume alone would suggest.
• It explains why ambient temperature affects performance. On a hot summer day, the condenser outside is trying to dump heat into already-warm air. This reduces efficiency and can push a borderline-sized unit beyond its capacity, which is exactly when you notice your room struggling to hold temperature.

Understanding this helps when diagnosing problems and when specifying equipment. If the heat load going in exceeds what the unit can remove, the room will never reach its target temperature, regardless of how new the kit is.

Cold Storage Temperature Ranges by Product Type

Different products have different requirements, and mixing storage categories in a single room without understanding those ranges is a common and costly mistake.

Fresh Meat and Poultry

The recommended storage temperature for raw meat and poultry is 0°C to +2°C. At this range, bacterial growth is significantly slowed. Temperatures above +4°C put you outside safe handling guidelines under UK food hygiene regulations.

Fish and Seafood

Fish is particularly sensitive and should be stored as close to 0°C as possible, ideally between -1°C and +2°C. Crushed ice storage sits at around 0°C, and your coldroom should match this if you are holding fresh catch.

Dairy Products

Milk, cheese, and butter are typically stored between +1°C and +4°C. Hard cheeses can tolerate slightly higher temperatures, but soft cheeses and cream products need to stay at the lower end of this range.

Fresh Fruit and Vegetables

Most produce stores well between +2°C and +8°C, but some items such as bananas, tomatoes, and certain tropical fruits are damaged by temperatures below +8°C. If you are storing mixed produce, aim for +4°C to +6°C as a practical middle ground.

Beverages and Drinks

Chilled drinks are typically held between +3°C and +8°C depending on the product. Lager and wine are often stored at the lower end; soft drinks and water at the higher end.

Beer Cellars

Beer cellars are a specific case worth understanding separately. The industry standard for a pub or bar cellar is +11°C to +13°C, with +12°C widely regarded as the ideal. This applies to cask ale, keg lager, and most draught products. Serving temperature at the tap will differ, but the cellar storage temperature is what determines product condition and line quality.

Traditional beer cellars are often actual underground rooms rather than purpose-built insulated coldrooms. Stone or brick construction provides some natural thermal mass, which helps buffer temperature swings, but it is not a substitute for proper insulation. An uninsulated cellar in a building with poor thermal performance will struggle to hold a consistent temperature year-round, particularly in summer when ground temperatures rise and heat conducts through the walls.

Lining a cellar with insulated coldroom panels makes a significant difference. It reduces the load on the cooling unit, improves temperature stability, and protects product quality. If you are running a cellar cooler that is working hard to maintain temperature in warmer months, poor insulation is usually the first thing to investigate.

Cask ale is particularly sensitive to temperature variation. Even a few degrees above the target range will accelerate secondary fermentation and shorten the viable serving window considerably.

Frozen Storage: It Is Not One-Size-Fits-All

Frozen is often treated as a single category, but different products have meaningfully different requirements, and specifying the wrong temperature can affect product quality, compliance, and energy costs.

General Frozen Food Stock

The UK and EU standard for frozen food storage is -18°C or below. This applies to the vast majority of commercial frozen goods including ready meals, frozen vegetables, bakery products, and general ambient-frozen stock. It is the baseline you will see referenced in food hygiene legislation.

Ice Cream and Dairy Desserts

Ice cream is more demanding than most people expect. For optimal texture and to prevent the formation of large ice crystals, ice cream should be stored at -22°C to -25°C. At -18°C, ice cream is technically safe but will often be softer than ideal and more prone to quality degradation during repeated door openings.

Fish and Seafood (Deep Frozen)

Deep-frozen fish is typically held at -18°C to -20°C, but high-value or sushi-grade product is often stored at -40°C or below to preserve cellular structure and prevent freezer burn over longer storage periods.

Pharmaceutical and Medical Cold Chain

Pharmaceutical frozen storage is governed by strict regulatory requirements rather than general food safety guidelines. Common ranges include:

• -20°C (±5°C) for standard pharmaceutical frozen storage covering vaccines, biologics, and some reagents
• -40°C to -80°C for ultra-low temperature (ULT) storage for certain biologics, plasma, and mRNA-based products

It is worth noting that standard coldroom refrigeration units are not designed for pharmaceutical ULT storage. This requires specialist equipment and validated monitoring systems.

Why Your Coldroom Might Not Be Holding Temperature

Knowing the target temperature is one thing. Achieving and maintaining it consistently is another. If your room is struggling to hold temperature, the refrigeration unit is rarely the first place to look.

Degraded Insulation

Coldroom panels contain insulation, typically polyurethane foam, that degrades over time, especially in older rooms. As insulation loses its effectiveness, the refrigeration unit has to work harder to compensate. In some cases, it simply cannot keep up, particularly during warmer months or when the room is heavily loaded.

A Damaged or Poorly Sealing Door

The door is the most used and most abused component in any coldroom. A worn gasket, a misaligned strike, a sagging hinge, or a handle that does not pull the door fully closed can all result in cold air escaping continuously. We covered how to diagnose door problems in detail in our previous post on coldroom door faults.

If your room is old and showing signs of both insulation degradation and door wear, the refrigeration unit is fighting on two fronts. Upgrading the kit without addressing the fabric of the room first is a common and expensive mistake.

Refrigeration Sizing: It Is About Cubic Capacity, Not Just Floor Space

One of the most misunderstood aspects of coldroom specification is how refrigeration units are sized. Floor dimensions get quoted frequently, such as a 3m x 3m room, but what actually matters to the refrigeration unit is the cubic capacity: length x width x internal height.

A room with high ceilings holds significantly more air volume than a low-ceilinged room with the same footprint, and that volume directly affects the load on the refrigeration unit. Specifying a unit based on floor area alone can leave you with an undersized kit that runs continuously, struggles to pull down to temperature, and wears out prematurely.

The other factor often overlooked is product load: how much warm product you are introducing into the room at any one time. A room that is being restocked with ambient-temperature goods several times a day has a very different refrigeration demand than one that is loaded once and left.

If you are unsure whether your current unit is correctly sized for your room, it is worth reviewing the cubic capacity and your typical loading pattern before assuming the unit itself is at fault.

Summary: Temperature Ranges at a Glance

Not Holding Temperature? Start with the Room, Not the Unit

If your coldroom is not reaching or maintaining its target temperature, the most productive place to start is an inspection of the room itself, covering door seals, hinges, handles, and panel condition, before looking at the refrigeration kit. In many cases, a relatively small repair makes a significant difference.

If you are specifying a new room or upgrading an existing one, browse our range of coldroom refrigeration units and monoblocks or get in touch for advice on sizing for your specific application.