Commercial Cold Rooms & Monoblock Units: UK Buyer's Guide 2026

Caterzone supplies commercial cold rooms and monoblock refrigeration units to UK restaurants, butchers, hotels, and food producers, and the cold room is the one purchase where getting the specification wrong is genuinely expensive to undo. A cabinet can be swapped in an afternoon. A cold room is built into your building.

This guide covers how modular panel cold rooms are constructed, the difference between monoblock and split refrigeration, what horsepower actually means in kilowatts, how to size a room against your delivery pattern, the UK regulations that apply — F-gas, EHO temperature control, and anti-entrapment door safety — and the real running costs. Browse the cold room and monoblock range as you read.

What is a modular cold room and how is it built?

A modular cold room is a walk-in refrigerated space assembled on site from prefabricated insulated panels, rather than built as part of the fabric of the building. The panels lock together with cam-locks so a room can be erected in a day, extended later, or dismantled and moved when a lease ends — a genuine advantage for tenanted UK sites.

Each panel is a sandwich: two sheets of coated steel bonded to a rigid polyurethane or PIR foam core. Core thickness is the number that matters. A 60mm core is adequate for a chiller in a temperate back-of-house area, 80mm to 100mm is the normal choice for a chiller in a warm kitchen, and 100mm to 120mm is standard for freezer rooms because the temperature difference across the panel is far greater.

Rooms are supplied with or without an insulated floor. A floor panel is the simpler option and gives a fully sealed box, but it creates a 100mm step that needs a ramp for trolleys and pallet trucks. A floorless room sits on a sealed, insulated screed and gives you a flush entrance — better for trolley traffic, but it must be specified with the building work rather than retrofitted.

Standard footprints start around 1.5m x 1.5m x 2.2m high and step up through 1.5m x 2.1m, 1.8m x 1.8m, 1.8m x 2.4m, and 2.1m x 2.1m. Because panels are modular, non-standard lengths are usually possible.

What is the difference between a monoblock and a split refrigeration system?

A monoblock is a single self-contained refrigeration unit that hangs on or through the cold room wall or ceiling, with the compressor, condenser, and evaporator all in one casing. A split (or remote) system separates the condensing unit — sited outside or in a plant area — from the evaporator inside the room, joined by pipework charged by an F-gas engineer.

Monoblocks win on installation. They arrive pre-charged and factory-tested, drop into a cut-out in the panel, and need only a power supply and a condensate drain. There is no site pipework and no gas charging, which typically saves several hundred pounds and a day of engineer time. Wall-mounted versions hang through the wall; overhead versions sit on the ceiling and suit rooms where wall space is tight.

Split systems win on heat and noise. A monoblock dumps its condenser heat straight into the room it sits in, so a monoblock cold room inside a hot kitchen fights the ambient temperature all day and works harder for it. A split system puts that heat outside. Splits are also quieter in the room and can serve larger volumes than a single monoblock sensibly can.

For most UK restaurants, takeaways, and small producers with a room under about 15m³ in a reasonably ventilated area, a monoblock is the right answer. Above that, or where the plant sits in a hot kitchen with no external wall, price a split.

What does 1hp mean, and what size unit do I need?

Horsepower is trade shorthand for compressor size, not a precise measure of cooling. As a working conversion, 1hp is about 0.75kW of compressor input and delivers roughly 1.5kW to 2.5kW of cooling duty at chiller temperatures, depending on the refrigerant and the evaporating temperature.

What matters is duty against room volume, insulation, ambient temperature, door openings, and — the one operators forget — the pull-down load from warm deliveries. A room that receives a chilled delivery of 200kg at 8°C every morning has a bigger peak load than the same room holding stable stock.

As a rough guide for a chiller at +2°C to +12°C in a UK kitchen with 80mm panels: 1hp suits roughly 5m³ to 8m³ (a 1.5m x 1.5m or 1.5m x 2.1m room), while 1.5hp covers roughly 8m³ to 14m³ (1.8m x 1.8m up to 2.1m x 2.1m). Freezer rooms need substantially more duty for the same volume — expect to move up a size compared with a chiller of identical dimensions.

Always let the supplier confirm duty against your actual room, ambient, and product load. An undersized unit never reaches temperature on a hot August afternoon, which is precisely when your EHO inspection is least welcome.

Chiller or freezer room — which do you need?

Chillers and freezer rooms use the same panels but different unit ratings, defrost strategies, and door hardware. A chiller monoblock is rated +2°C to +12°C and is set in practice to hold 0°C to 5°C, comfortably inside the UK legal maximum of 8°C for chilled food. A freezer monoblock is rated −25°C to −2°C and is set to hold −18°C or colder.

Freezer rooms need heated door frames and heated drain lines to stop ice bridging the seal, and they need scheduled defrost cycles. They also need more insulation, which eats internal space: a 1.8m x 1.8m external footprint with 120mm panels gives noticeably less usable floor than the same footprint at 60mm.

Most UK sites are better served by a generous chiller plus separate freezer cabinets or a chest freezer than by a small freezer room, unless frozen stock genuinely runs to pallets. Frozen volume is easier to distribute across cabinets than chilled volume, because chilled stock needs daily walk-in access.

Cold room and monoblock cost comparison

Option	Typical spec	Suits	Guide price
1hp wall monoblock	+2°C to +12°C, 450x880x730mm	Replacing plant on an existing chiller	£1,589.95
1hp overhead monoblock	+2°C to +12°C, ceiling mounted	Rooms with no spare wall	£1,565.95
1.5hp wall monoblock	+2°C to +12°C, 600x860x750mm	Larger chillers, warm plant areas	£1,678.95
1.5hp freezer monoblock	−25°C to +2°C	Walk-in freezer rooms	£1,764.95
1.5m x 1.5m room + 1hp	2.2m high chiller, complete	Cafés, small restaurants	£3,403.95
1.8m x 2.4m room + 1hp	2.2m high chiller, complete	Hotels, butchers, producers	£4,050.95

Budget separately for delivery and offload, a competent electrical supply, a condensate drain, and — for a floorless room — the insulated screed. Shelving is almost always extra and almost always needed.

How do you size a cold room against your business?

Size the room around your delivery cycle, not your daily usage. If you take a chilled delivery twice a week, the room must swallow the whole delivery on day one with room to work, not merely hold an average day's stock.

A practical method: count the gastronorm pans, crates, and boxes you hold at your fullest point of the week, then allow 0.4m to 0.5m of shelf depth on three walls with a 700mm to 800mm clear walkway down the middle. A 1.5m x 1.5m room gives roughly 4.5 linear metres of usable shelving across four tiers. A 1.8m x 2.4m room gives around 8 linear metres and takes trolleys and full crates comfortably.

As a rough starting point, a 60 to 80 cover restaurant taking two chilled deliveries a week is usually well served by 1.5m x 2.1m. A busy 150 cover hotel kitchen, a butcher, or a producer running cook-chill batches normally needs 1.8m x 2.4m or larger.

Leave headroom. Every operator who buys the smallest room that fits today's stock is buying a second fridge within eighteen months, and the marginal cost of one extra panel bay is far lower than the cost of a second refrigeration system.

What UK regulations apply to a walk-in cold room?

Four sets of rules matter, and one of them is a life-safety issue.

Door safety. Every walk-in cold room and freezer must have a door that can be opened from the inside, even when locked from the outside, plus an internal safety release. Freezer rooms should also carry an internal alarm push. This is not optional refinement — people do get shut in, and in a freezer room that is a genuine emergency. Test the release at every service visit and record it.

F-gas. Systems containing fluorinated refrigerants must be leak-checked by a certified engineer at defined intervals once the charge reaches 5 tonnes CO₂ equivalent, with records retained. Most small monoblocks sit below that threshold, but the obligation to prevent leakage and to use certified engineers for any work on the circuit applies regardless of charge. Increasingly, small monoblocks use R290 (propane), which is efficient and low-GWP but flammable — it carries charge limits and installation conditions, so it must be sited and serviced accordingly.

Food temperature control. Chilled food must be held at 8°C or below in England, Wales, and Northern Ireland; most operators set 0°C to 5°C to leave a margin. Frozen stock should be held at −18°C or colder. You need monitoring and records — a calibrated digital thermometer with a daily log at minimum, or a continuous monitoring system with alarms for a room holding high-value stock.

Electrical and installation. Monoblocks up to about 1hp often run on a 13A supply, but larger units and freezer plant frequently need a dedicated circuit. Have the supply confirmed by a qualified electrician, PAT test plug-connected equipment, and keep commissioning paperwork with your HACCP file.

What does a cold room cost to run and maintain?

A 1hp chiller monoblock draws roughly 0.75kW to 1.1kW when the compressor is running, and typically runs 40% to 60% of the time in a well-insulated room. That is somewhere around 8kWh to 14kWh a day. At a commercial rate of about 25p per kWh, expect roughly £2 to £3.50 a day, or £700 to £1,300 a year. A freezer room of similar size will run appreciably higher.

Three things move that number more than anything on the data plate. Keep the condenser clean — a dust-blocked condenser can add 20% or more to running cost and is the single most common cause of a room drifting warm. Keep the door discipline tight, because a strip curtain and a properly adjusted door closer pay for themselves quickly. And keep the room stocked but not packed, because airflow around the evaporator matters more than operators expect.

Service the system twice a year, check door seals and the safety release monthly, and clear the condensate drain regularly. A well-maintained modular cold room will run for 15 years or more, and the panels usually outlast two sets of refrigeration plant.

Frequently asked questions

How much does a commercial cold room cost in the UK?

A complete 1.5m x 1.5m x 2.2m chiller with a 1hp monoblock costs around £3,400, and a 1.8m x 2.4m room around £4,050. Monoblock units bought separately run from roughly £1,566 for a 1hp chiller unit to £1,765 for a 1.5hp freezer unit. Add delivery, electrical work, and shelving.

Do I need planning permission for a cold room?

An internal modular cold room is normally a fit-out rather than a building alteration, so planning permission is rarely needed. An external cold room, or one requiring a condensing unit mounted outside, may need consent — particularly on a listed building, in a conservation area, or where noise could affect neighbours. Check with your local authority before ordering.

What temperature should a walk-in cold room be set to?

Set a chiller to hold 0°C to 5°C. UK law requires chilled food at 8°C or below, so a 5°C setpoint gives working margin for door openings and deliveries. Set a freezer room to −18°C or colder. Log the temperature at least daily with a calibrated thermometer and keep the records with your HACCP paperwork.

Can I install a monoblock cold room myself?

Panels can be assembled by a competent fitter, and a pre-charged monoblock avoids the need for site gas charging. The electrical supply, however, must be installed and certified by a qualified electrician, and it is worth having a refrigeration engineer commission and log the unit. Self-installation without commissioning records commonly complicates warranty claims.

How long does it take a cold room to reach temperature?

An empty, correctly sized chiller typically pulls down from ambient to 5°C in two to four hours. A freezer room takes eight to twelve hours to reach −18°C. Always pull the room down and confirm it holds temperature over a full 24 hours before loading stock, and never load a warm room with a chilled delivery.

Is a cold room cheaper to run than several upright fridges?

Usually yes, per litre of storage. One correctly sized refrigeration system is more efficient than four separate cabinets with four compressors, and a walk-in wastes far less air on door openings per unit of stock. The trade-off is upfront cost and floor space, so cold rooms pay off where storage volume is genuinely high.

Where to buy cold rooms and monoblock units in the UK

Caterzone supplies complete modular cold rooms and standalone monoblock refrigeration units for UK kitchens, with delivery nationwide from Northampton. Browse the cold room and monoblock collection, or start with the 1.5m x 1.5m cold room with 1hp wall-mounted monoblock at £3,403.95 for a café or small restaurant, step up to the 1.8m x 2.4m cold room with 1hp monoblock at £4,050.95 for a hotel or butchery, and for a plant replacement specify the 1.5hp wall-mounted monoblock unit at £1,678.95. For frozen storage, the 1.5hp freezer room monoblock is £1,764.95.

To plan the rest of your cold chain, read our guide to sizing commercial refrigeration and our under-counter fridge versus walk-in comparison. To size a room against your delivery pattern, call Caterzone on +44 7787 069044 or email info@thecaterzone.co.uk.