A cold-room floor must provide insulation, hygiene and enough strength for the real load.

In short: freezer floors need a continuous insulation and moisture-control design. A positive-temperature room may sometimes use a suitable building slab instead of a panel floor.

Omitting the panel floor is only acceptable where the slab is level, sealed, hygienic, load-bearing and thermally suitable. In the Frostbox range, the no-floor option applies to the specified 80 mm chiller configuration, not to every room.

For freezers, assess ground frost and possible frost heave. The solution may include an insulated panel floor or a designed building floor with vapour control and, where required, subfloor protection.

Select the finish for people, racks and vehicles. Never assume a floor suitable for shelving is suitable for a pallet truck.

How floor panels differ

Floor panels are built to the same sandwich principle as wall and ceiling panels but are reinforced and finished for load-bearing duty.

Reinforced structure — a steel or aluminium internal framework distributes point loads (pallet feet, shelving legs) across the foam core so it isn't crushed.
Anti-slip surface — a textured or chequer-plate finish reduces slip risk in a cold, often wet, environment.
Load ratings — MTH publishes three named floor types, not two. Pedestrian: 1,500 kg/m², reinforced: 3,000 kg/m², drive-in: 4,000 kg/m².
Traffic classes — pedestrian floors are for foot traffic and shelving. Hand pallet trucks and pallets need the reinforced floor; forklifts need the drive-in floor. A loading ramp is available where forklifts or pallet trucks enter the room.

Load-rating note: Match the floor to your real traffic, not just to the static weight of the goods. The published rating is a distributed load in kg/m²; wheels and pallet feet concentrate the same weight onto a far smaller area, so a load that looks safe per square metre can still exceed what the panel takes at a single point. If a pallet truck ever crosses the threshold — even occasionally, even empty — specify the reinforced floor rather than the pedestrian one.

When you need a floor panel — and when you don't

An insulated floor is essential for freezer rooms and for any room built directly over an unconditioned or heated space (e.g. on an upper storey, or above a boiler room). For freezers on a ground slab, floor insulation prevents the slab freezing (frost-heave risk); for rooms above an unconditioned or heated space, it blocks heat gain from below.

A floor panel may be omitted for some chiller applications sitting on a suitable insulated slab. In the Frostbox range, the "without floor" option is offered specifically for the Cold Room 80 mm configuration, where the existing floor is level, sealed, and thermally adequate.

Omitting the floor lowers cost and removes the small threshold step, but it shifts responsibility for floor insulation, levelness, and moisture sealing onto the building slab — so confirm the slab specification before choosing it.

Room type	Floor panel
Standard chiller on a sound insulated slab	Optional — Cold Room 80 mm "without floor" only
Meat/fish chiller, low-temp processing	Recommended
Any freezer	Required
Room over unconditioned / heated space	Required

With-floor vs floorless corner detail — two vertical wall sections with the same internal height H. A, insulated floor: the wall stands on an insulated floor of the same thickness t, with an anti-slip surface and a threshold at the door; external height H + 2 × t. B, cold room 80 mm only: the wall stands directly on the slab, no threshold; external height H + 1 × t; the slab must be level, sealed and insulated — responsibility passes to the building. Freezer card: always the set of 3 — insulated floor, pressure-equalisation valve, heater in the door frame and threshold. — With or without an insulated floor

Freezer rooms (BT): three things that are never optional

MTH calls the low-temperature version of the room BT — the freezer build, run at negative temperatures (in the Frostbox range −18 °C to −22 °C). The manufacturer's manual is explicit that a BT room is never installed without a floor, and that it must always be fitted with three things together:

A floor panel
A pressure-equalisation (compensation) valve
A heater on the door panel

Warning: These three are a set, not a menu. Do not install a BT (low-temperature) room without a floor. The "without floor" option exists for positive-temperature rooms only — in the Frostbox range, for the Cold Room 80 mm configuration.

Why the floor is mandatory

A freezer with no insulated floor cools the slab it stands on until the ground beneath is below freezing. Moisture in that ground freezes and expands, and the resulting frost heave lifts and cracks the slab — and the room standing on it. The floor panel is also the load-bearing element the room is engineered around, so leaving it out changes how the walls are supported, not only how the room insulates.

Why a pressure-equalisation valve

Every time the door opens, warmer, moister air enters the room. When the door closes, that air is chilled to freezer temperature within minutes — and as it cools it contracts. In a well-sealed, well-insulated box, the pressure inside therefore drops below the pressure in the room outside, and the difference presses on the whole door area at once.

The consequences are practical, not theoretical: the door can be effectively impossible to open for a period after closing, and the gasket, hinges, and panels are loaded in a direction they were not designed for. A pressure-equalisation valve — also called a compensation valve — is a small vented fitting through a wall panel that lets a little air pass in whichever direction is needed to level the two pressures, so the door stays openable and the envelope is not pulled on.

MTH requires the valve on BT rooms specifically. At chiller temperatures the temperature step the incoming air goes through is far smaller, so it contracts far less and the pressure difference stays negligible; at freezer temperatures it does not.

Why the door panel needs a heater

The door frame is where the coldest surface in the building meets warm, humid room air. At freezer temperatures, moisture from that air condenses on the frame and threshold and freezes there, so the gasket loses its seal or the door freezes shut altogether. A heater in the door panel keeps the frame above freezing so that ice cannot take hold; MTH's brochure lists a heating cable in the frame and threshold, for temperatures down to −25 °C, specifically to prevent icing.

If a freezer door in service is icing at the frame or sticking shut, the frame heater is the first thing to check — the frame should feel warm to the touch. See Ice on the door frame and Door freezing shut.

Requirements for BT rooms are taken from the MTH Algor installation and maintenance manual. Download the documents

Specifications reflect the MTH Algor panel system supplied by Frostbox. Load ratings and the "without floor" option are confirmed per configuration — contact [email protected].