Insulated panel sizes are standardised at an effective width of 950 mm to 1,150 mm (about 37.4 to 45.3 inches), a length cut to order up to 15 m (49.2 feet), and a core thickness of 50 mm to 200 mm (2 to 7.9 inches) depending on the core material. The three most common panel types in industrial cold storage construction in Vietnam are EPS, PU and Rockwool, each with a different thermal conductivity and temperature application.
From 20 years of advising on and installing more than 500 cold storage and freezer projects, the engineering team at Tan Long finds that the most common mistake investors make is choosing panel thickness on price rather than on the store’s actual operating temperature. That mistake raises electricity costs by 15% to 30% a year through continuous heat loss through the walls.
This article gives the standard size tables for each panel type, a comparison of technical specifications, guidance on choosing thickness by cold store temperature, and an analysis of how the joint design affects real insulating performance.
What an insulated panel is and how it is built
An insulated panel is an advanced building material made as a flat board with a distinctive three-layer structure. The two faces are powder-coated aluminium-zinc alloy coated steel 0.3 mm to 0.6 mm thick, tightly enclosing the insulating core between them. This sandwich structure gives the product structural strength, insulation and complete water resistance at once.
In refrigeration system design, panel size determines the heat loss calculation and the best use of the installation space. The steel facing protects the panel mechanically and against chemical corrosion, while the central core (PIR, PU or EPS) determines the insulating performance and fire behaviour. Panels connect through a tongue-and-groove or Z-lock joint system, forming a tightly sealed whole that eliminates thermal bridging at the junctions.
In cold storage construction, panels are the perfect replacement for traditional brick walls. Being 7 to 10 times lighter and 3 to 4 times faster to erect, choosing the right panel size for the scale of the project saves on materials and significantly improves the building’s insulation.
Depending on the required storage temperature, Tân Long’s engineers will recommend the appropriate core — PIR insulated panels for deep-freeze rooms or EPS panels for chill rooms — for reliable performance and the lowest possible energy use.
Insulated panel sizes by core material
In industrial construction, panel size is set strictly by the production line standard and the particular requirements of each project. The effective width is normally fixed by the machine, while the length is cut to suit the project drawings and the core thickness is the parameter the investor chooses to optimise thermal performance.
EPS panel sizes (white foam)
EPS panels have two faces of powder-coated aluminium-zinc alloy coated steel 0.3–0.6 mm thick. The core is EPS (expanded polystyrene) foam at a density of 8–20 kg/m³.
| Parameter | Size |
|---|---|
| Effective width | 950 mm or 1,150 mm (37.4 in / 45.3 in) |
| Overall width | 1,000 mm or 1,200 mm |
| Length | Cut to order, maximum 15 m (49.2 feet) |
| Core thickness | 50mm, 75mm, 100mm, 125mm, 150mm, 170mm |
| Core density | 8–20 kg/m³ |
| Thermal conductivity λ | 0,033–0,038 W/(m.K) |
| Facing thickness | 0,3–0,6mm |
This panel type is typically used for cold storage for produce, fruit and vegetables (above freezing), or as wall cladding for workshops and modular offices. It is the most cost-effective material in the basic insulation segment.
PU (polyurethane) panel sizes
Compared with EPS, panel size PU differs slightly in effective width to guarantee a completely tight fit when the joint system is installed. PU has the lowest thermal conductivity and is the usual choice where insulation requirements are demanding.
| Parameter | Size |
|---|---|
| Effective width | 1,000 mm or 1,100 mm (39.4 in / 43.3 in) |
| Overall width | 1,050 mm or 1,150 mm |
| Length | Cut to order, maximum 15 m (49.2 feet) |
| Core thickness | 50mm, 75mm, 100mm, 125mm, 150mm, 200mm |
| Core density | 36–42 kg/m³ |
| Thermal conductivity λ | 0,020–0,024 W/(m.K) |
| Facing thickness | 0,3–0,6mm |
Insulating around 40% better than EPS at the same thickness, PU insulated panels are the first choice for seafood freezing rooms, pharmaceutical stores and flagship cold storage projects holding deep-freeze temperatures from −18°C to −25°C. At Tân Long we always recommend that investors calculate panel size carefully in terms of thickness, to reduce compressor running costs over the long term.
Rockwool (mineral wool) panel sizes
Where fire safety requirements are demanding, panel size Rockwool is manufactured to meet current fire certification. The product comprises two powder-coated aluminium-zinc alloy coated steel faces enclosing a mineral wool core at a density of 32 kg/m³ to 120 kg/m³.
| Parameter | Size |
|---|---|
| Effective width | 950 mm or 1,150 mm (37.4 in / 45.3 in) |
| Length | Cut to order, maximum 15 m (49.2 feet) |
| Core thickness | 50mm, 75mm, 100mm, 125mm, 150mm, 175mm, 200mm |
| Core density | 32–120 kg/m³ |
| Thermal conductivity λ | 0,033–0,045 W/(m.K) |
| Temperature range | Up to 750°C |
| Fire rating | EI 30, EI 60 or EI 90 depending on thickness |
Using the correct panel size in mineral wool secures an EI 30, EI 60 or EI 90 fire rating depending on core thickness. It is mandatory for chemical plants, transformer rooms and cold storage construction projects requiring fire safety to TCVN standards. However, because its thermal conductivity is higher than PU, Rockwool is not usually the choice for deep-freeze rooms.
Glasswool (glass wool) panel sizes
Alongside fire performance, panel size Glasswool is usually specified to optimise sound absorption. Its fine, resilient glass fibre structure gives better acoustic performance at low frequencies.
| Parameter | Size |
|---|---|
| Effective width | 950 mm or 1,150 mm (37.4 in / 45.3 in) |
| Length | Cut to order, maximum 15 m (49.2 feet) |
| Core thickness | 50mm, 75mm, 100mm, 125mm, 150mm, 175mm, 200mm |
| Core density | 32–120 kg/m³ |
| Thermal conductivity λ | 0,030–0,044 W/(m.K) |
In restaurants, studios and noisy production areas, Glasswool panel partitions improve the working environment considerably. Glasswool is also more affordable than premium Rockwool.
XPS and acoustic panel sizes
For particular applications such as floors or areas of extremely high humidity, panel size XPS (extruded polystyrene) is the specification to note. XPS panels have an effective width of 950 mm or 1,150 mm and a maximum length of 15 m. XPS core thicknesses are 50 mm, 75 mm and 100 mm, with a density of 36–40 kg/m³. XPS resists moisture better than EPS, making it suitable for cold store floors exposed to high humidity.
Acoustic Rockwool panels have an effective width of 1,160 mm (45.7 inches) and a maximum length of 15 m. Core thicknesses are 50 mm, 75 mm and 100 mm, with a core density of 100 kg/m³ and a facing thickness of 0.3–0.5 mm. The higher core density compared with ordinary Rockwool improves sound absorption.
Summary comparison of insulated panel types
The table below compares the four common panel types directly against the technical criteria that matter most when specifying for cold storage.
| Criteria | EPS Panel | PU Panel | Panel Rockwool | Panel Glasswool |
|---|---|---|---|---|
| Thermal conductivity λ (W/m.K) | 0,033–0,038 | 0,020–0,024 | 0,033–0,045 | 0,030–0,044 |
| Core density (kg/m³) | 8–20 | 36–42 | 32–120 | 32–120 |
| Standard thicknesses (mm) | 50–170 | 50–200 | 50–200 | 50–200 |
| Effective width (mm) | 950 / 1.150 | 1.000 / 1.100 | 950 / 1.150 | 950 / 1.150 |
| Fire resistance | Low | Medium | High (up to 750°C) | Medium to high |
| Sound insulation | Medium | Medium | Good | Good |
| Moisture resistance | Medium | Good | Poor when wet | Poor when wet |
| Operating temperature range | 0°C to +30°C | −40°C to +100°C | −50°C to +750°C | −50°C to +250°C |
| Cold storage applications | Cool storage | Freezer rooms, chill rooms | Plant rooms, fire protection | Sound insulation |
| Relative cost | Lowest | Medium to high | Medium | Low to medium |
How to choose panel thickness by cold store temperature
This is the most important question in cold store design. Panel thickness directly affects the initial investment, the annual electricity cost, and the ability to hold a steady temperature inside the store.
The core principle: the lower the operating temperature, the larger the difference between inside and outside, the greater the heat loss through the walls, and the thicker the panel has to be to compensate.
Guide to choosing panel thickness by store temperature:
| Warehouse type | Operating temperature | Recommended PU panel | Equivalent EPS panel |
|---|---|---|---|
| Air-conditioned room | +18°C to +25°C | 50mm | 75mm |
| Chill room for vegetables | +2°C to +15°C | 75mm | 100mm |
| Chill room for fresh meat | 0°C to +4°C | 100mm | 150mm |
| Cold store for seafood | -5°C to -10°C | 100mm–125mm | 150mm–170mm |
| Freezer store for food | -18°C to -22°C | 150mm | Not recommended |
| Deep-freeze rooms (IQF freezing) | -25°C to -35°C | 200mm | Not recommended |
| Industrial blast freezing tunnels | -35°C to -45°C | 200 mm (double wall) | Not recommended |
With cold storage operating at −18°C in southern Vietnam (average outdoor temperature 32°C, or 89.6°F) faces a temperature difference of 50°C (122°F). At that difference, a 150 mm PU panel has a heat transfer coefficient of U ≈ 0.146 W/(m².K), keeping heat loss within the design allowance.
Choosing a 100 mm PU panel instead of 150 mm to save on materials means the refrigeration plant has to make up roughly 30% more heat load, equivalent to 20–25% more electricity every year for the life of the store.
Panel joints: the factor that decides real insulating performance
Many investors focus on panel thickness but overlook the joint system, which in practice is the most common weak point in the insulation. An open or badly fitting joint creates a thermal bridge, where heat passes quickly from outside into the store.
There are three common joint types:
- Tongue & groove: The most common joint, quick to install, suitable for office and workshop partitions where a completely airtight seal is not required. The gap at the joint runs from 0.5 to 1.5 mm.
- Z-lock: The Z-shaped lock design gives a tighter joint than tongue and groove, reducing thermal bridging at the contact point. It suits cold stores from −18°C to −25°C and cleanrooms with strict temperature control.
- Camlock: A mechanical lock fitted inside the panel applies even clamping force along the whole joint. It is the tightest option, used on deep-freeze rooms at −35°C and industrial blast freezing tunnels. It costs more, but heat loss at the joint is 60–70% lower than with a conventional tongue-and-groove joint.
Advantages of insulated panels over traditional brick walls
In 20 years of design consultancy on industrial refrigeration system, Tân Long has found six core advantages of insulated panels over traditional building materials in cold storage:
- Light weight: Panels weigh 10–25 kg/m² depending on type, 8 to 20 times lighter than a brick wall (roughly 200–300 kg/m²). Foundations and steel frames can be significantly lighter, saving 15–25% of the structural cost.
- Fast erection: A team of four can install 80–120 m² of panel in an 8-hour working day. Bricklaying and rendering runs at 15–20 m² per person per day with a team of four. Panels cut a cold store programme from 3–4 months to 4–6 weeks.
- Superior insulation performance: A 100 mm PU panel has a heat transfer coefficient of U ≈ 0.22 W/(m².K). A 200 mm (7.9 inch) brick wall rendered both sides is U ≈ 1.8–2.0 W/(m².K). The panel insulates 8 to 9 times better.
- Flat, sealed surfaces that are easy to clean: Powder-coated galvanised steel surfaces are non-absorbent and do not harbour bacteria, meeting HACCP and BRC hygiene standards for food cold storage.
- Long design life: Operated correctly, insulated panels have a design life of 20–30 years. Aluminium-zinc alloy coated facings (AZ150) resist corrosion in a cold, humid environment better than ordinary galvanised steel.
- Demountable: Panels can be taken down and reused elsewhere when a cold store is extended or relocated, preserving the value of the investment.
Applications of insulated panels in industrial refrigeration
Insulated panels form the envelope of cold stores, freezer rooms and blast freezing tunnels, but their use goes well beyond cold storage alone. Below are the main applications Tân Long has delivered in practice:
- Industrial food cold storage: This is the core application. Cold stores for seafood, meat and export fruit and vegetables need a PU panel envelope from 100 mm to 200 mm with Z-lock or camlock joints, holding −18°C to −25°C.
- Cleanrooms for food and pharmaceutical production: PU panels with a white powder-coated steel face meet ISO 14644 hygiene requirements for cleanrooms from ISO 7 to ISO 5.
- Food production workshops: Partitions between preparation, processing and packing areas use 75 mm EPS or 75 mm PU panels with a light-coloured, easily cleaned surface, meeting HACCP requirements.
- Laboratories and research centres: Rooms holding biological samples, vaccine research facilities and blood banks requiring ±0.5°C control use 100 mm–150 mm PU panels together with purpose-made cold room doors.
- Pharmaceutical and medical cold storage: Storing vaccines (+2°C to +8°C) and freeze-dried pharmaceuticals (−20°C to −80°C) in line with GDP (Good Distribution Practice) requires PU panels from 100 mm to 150 mm.
Combining panel walls with properly specified insulated cold storage door turns the whole envelope into a continuous insulating shell. After the panel joints, the cold room door is the second weakest point in the insulation if the wrong type is chosen or it is badly fitted.
How to store insulated panels correctly
Installed insulated panels last a long time if the store is operated and maintained properly. Many installations, however, fall below 10 years because of the following common mistakes.
- Avoid mechanical impact on the panel surface, particularly during forklift movements. A heavy knock crushes the core locally, creating a cold spot where condensation then forms. Fitting stainless steel corner guards at vulnerable points is an effective precaution.
- Clean panel surfaces with clean water or a neutral detergent twice a month. Do not use strongly acidic or alkaline chemicals (pH < 4 or pH > 10), which strip the powder coating.
- Check the joints between panels every 6 months. If a gap or separation appears at a joint, inject PU foam to seal it and apply purpose-made tape immediately. A 1 mm gap along a 10 m joint causes heat loss equivalent to 1 m² of panel missing entirely.
- Store uninstalled panels under cover, out of direct sunlight and away from high humidity. Stack them flat on a level rack; do not stand them on edge, because the core warps over time.
Insulated panel sizes are standardised at an effective width of 950 mm to 1,150 mm, a length cut to order up to 15 m, and a core thickness of 50 mm to 200 mm. Choosing the right type and thickness is the most important technical decision in cold store design, affecting electricity costs directly across the building’s 20–30 year life.
PU panels are the standard for industrial cold and freezer stores thanks to a thermal conductivity of λ = 0.020–0.024 W/(m.K), the lowest of the common panel types. EPS panels suit chill rooms and general construction. Rockwool panels are used where fire performance is the first priority.
Tân Long has more than 20 years of experience advising on, designing and installing industrial refrigeration systems on over 500 projects in Vietnam, including cold stores for Kyokuyo Vina Foods, Lotte F&G, C.P. Vietnam and Frescol Tuna. Our engineers are ready to advise and calculate the exact quantity, type and thickness of panel for your project.
- Contact us for free advice: Hotline: (+84) 933 357 058 (Mr. Thinh)
- Email: info@tanlongvn.com
- Monday to Saturday: 8:00 AM to 5:30 PM
Frequently asked questions about panel sizes
What is the effective width of a panel?
The standard effective width is 950 mm (37.4 inches), 1,000 mm (39.4 inches) or 1,150 mm (45.3 inches) depending on the panel type and manufacturer. The overall width is 50–100 mm greater to form the overlapping joint.
What is the maximum panel length?
The maximum length is usually 15 m (49.2 feet), limited by transport on an articulated truck. The length is cut to suit the project, minimising waste and avoiding unnecessary joints.
How thick does a panel need to be for a −18°C cold store?
A freezer store holding food at −18°C to −22°C needs PU panels at least 150 mm (5.9 inches) thick on the walls and 150 mm–200 mm on the ceiling and floor. EPS panels would need at least 200 mm, but are not recommended because they insulate less well.
Is EPS or PU better for a cold store?
PU panels outperform EPS panels in cold storage at any temperature, with a thermal conductivity 35–40% lower. At the same 100 mm thickness, PU reduces heat loss considerably better than EPS. EPS suits chill rooms only (+2°C to +15°C) and projects where the priority is keeping initial material costs down.
What temperatures can a panel withstand?
PU panels withstand −40°C to +100°C (−40°F to 212°F). Rockwool panels withstand up to 750°C (1,382°F) and are used where fire protection standards require it. EPS panels are unsuitable above +80°C because the foam core starts to deform.
How much does an insulated panel cost?
Panel prices vary by type, thickness and supplier. For a current price list and technical advice matched to your project, contact the Tân Long team directly for an accurate quotation.
Frequently asked questions about insulated panel sizes
What is an insulated panel?
It is a three-layer board — two steel facings sandwiching an insulating core — used to build the envelope of cold stores, cleanrooms and workshops needing insulation.
What should panel thickness be based on?
Mainly on the store’s operating temperature range: the colder the store, the greater the difference from ambient, and the thicker the panel needs to be to reduce cooling losses and prevent condensation on the outside of the envelope.
Can a thinner panel be chosen to save money?
No. The extra cost of a thicker panel is a one-off, whereas the cooling losses from a thin panel are paid in electricity every month for the life of the store — usually far more than the initial saving.
How does the panel joint affect the quality of the store?
The joint determines how tight the seal is. A poor joint creates a thermal bridge and lets moisture into the panel core, reducing its insulating value and causing condensation and icing at the joint.
What advantages do insulated panels have over a brick wall?
Fast erection, light weight so less structural load, far better insulation at the same thickness, a smooth surface that is easy to clean, and the ability to dismantle and relocate when needed.
Does Tân Long supply and erect cold storage panels?
Yes. Tân Long supplies panels with matched accessories and erects the envelope, together with a complete refrigeration system.
