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Walk-in Freezer primarily uses PU/PIR sandwich panels, which offer excellent thermal insulation and superior waterproofing and moisture resistance. Different panel thicknesses are suitable for different temperatures and application scenarios. Generally, the thicker the panel, the better the insulation performance.   For walk-in freezer units with different temperature requirements, different PU/PIR sandwich panels can be selected:   1. -18℃ ~ -25℃ cold storage: 150mm PIR sandwich panels can be used for storing various aquatic products, meat products, and frozen foods;   2. -25℃ ~ -30℃ deep-temperature cold storage: 180mm and above PIR sandwich panels can be used for long-term storage of high-end seafood and meat, as well as freezing of ice cream and dairy products;   3. -30℃ ~ -40℃ ultra-low temperature cold storage: PIR sandwich panels with a thickness of 200mm or more must be used for long-term storage of deep-sea aquatic products, high-end seafood, and high-end beef and mutton.   4. Deep cryogenic storage at -40℃ and below: Requires 250mm thick PIR sandwich panels for the long-term preservation of vaccines, plasma, biological samples, viral strains and other biomedical and research materials, special industrial materials (such as aerospace materials and chemicals) and rare agricultural and insect specimens.

The cold storage sandwich panels are generally refers to the PU/PIR sandwich panels,which has best thermal insulation performance,are widely used in various low-temperature roofs and walls.   Common applications as below:   1. Various cold storage systems: ambient temperature cold storage, low temperature freezing storage, constant temperature and humidity warehouses, pre-prepared food warehouses and kitchens, etc.   2. Food factories and workshops: fruit and vegetable preservation and processing workshops, poultry slaughterhouses, aquatic product processing workshops;   3. Various cold chain logistics warehouses: logistics park cold storage, ambient temperature cold chain warehouses, low temperature cold chain warehouses, cold chain distribution centers, etc.   4. Agricultural products and aquaculture: crop seed storage warehouses, low temperature mushroom storage warehouses, agricultural product storage warehouses; low temperature aquatic and seafood storage warehouses, etc.;   5. Pharmaceuticals and chemicals: vaccine cold storage, pharmaceutical storage cold storage, low temperature sterile laboratories, biobanks, low temperature chemical storage, explosion-proof cold storage, etc.;   6. Commercial and mobile cold storage: container mobile cold storage, refrigerated trucks, supermarket cold storage rooms, frozen warehouses, etc.

Sandwich panels, used for walls and roofs, are widely used in various steel structure factories, large warehouses, clean rooms, logistics warehousing, and cold storage facilities due to their excellent thermal insulation performance, high strength, good waterproof performance, light weight, easy installation, and short construction period. The significant advantages of sandwich panels are as follows:   1. Excellent thermal insulation performance: Sandwich panels typically use EPS, rock wool, and polyurethane as insulation core materials, providing excellent insulation performance without the need for additional insulation layers;   2. High structural strength, wind resistance, and strong corrosion resistance: Sandwich panels use color-coated galvanized steel sheets as the base material, resulting in high structural strength and good wind resistance. The surface can be coated with highly weather-resistant and fluorocarbon coatings, offering good corrosion resistance and aging resistance;   3. Excellent sound insulation and fire resistance: Different sandwich panel core materials can be selected to meet different application requirements. For example, large logistics warehouses can choose Class A fire-resistant rock wool core materials; large computer rooms can choose glass wool core materials with good sound insulation; and cold storage can choose polyurethane core materials with better thermal insulation performance.   4. Good sealing and waterproofing: Sandwich panels are generally sealed with tongue and groove joints and sealant, resulting in good waterproofing performance.   5. Lightweight, quick construction, and short construction period: Compared with traditional wall panels, sandwich panels are lighter and suitable for light steel structures and roof and wall renovations. They can be directly assembled on-site, simplifying construction, shortening the construction period, and greatly reducing labor costs.   6. Beautiful appearance and high cost performance: The surface of sandwich panels is made of color steel plate, which can be designed and selected in different colors, making them beautiful and elegant. Furthermore, color steel plates have a long service life, are easy to maintain, and offer high overall cost performance.  

Insulated wall panels are composite wall panels made of two layers of rigid plates (such as metal plates, cement plates, etc.) and one layer of insulation core material (such as EPS, PU, rock wool, glass wool, aluminum honeycomb, etc.).   Traditional walls are generally made of bricks and cement mortar or poured concrete.   The specific differences between the two are as follows:   1. Construction methods: Insulated wall panels can be directly installed on steel structures without additional insulation; traditional wall have complex construction processes, requiring separate insulation after the wall is built.   2. Construction cycles: Insulated wall panels are integrated panels that can be directly installed; the construction cycle is short, generally about 4 weeks for a small factory to complete installation; traditional wall have complex construction processes and a long construction period, generally several months for a small factory to complete.   3. Weight: Insulated wall panels are generally lighter, suitable for light steel structures and renovation of old houses; traditional wall are very heavy, placing high demands on the load-bearing capacity of the foundation and beams.   4. Significant differences in thermal insulation performance: The core material of insulated wall panels is a high-insulation material, providing excellent insulation; traditional wall, being cement concrete, have poor insulation performance and require separate insulation.   5. Structural strength and waterproofing performance: Insulated wall panels have waterproofing treatment at the joints, resulting in better waterproofing and wind resistance; the insulation layer of traditional wall is prone to peeling off, and inadequate waterproofing can easily lead to water seepage and cracking.   6. Different application scenarios: Insulated wall panels are mostly used in prefabricated modular houses, steel structure factories, large warehouses, clean rooms, cold storage, etc.; traditional wall are mainly used in residential buildings.

Start with fire safety. In the US, the International Building Code (IBC) sets the rules. Foam plastic insulation like polyurethane or PIR must pass big tests like NFPA 285. This test checks if flames spread on walls. If it fails, you can’t use it on some buildings. In Europe, EN 13501-1 rates materials from A1 (non-combustible) to F. Rock wool usually scores A1. PIR often scores B-s1,d0, meaning good fire safety and low smoke. Always get test reports from your supplier that prove the panels meet your local code. Energy codes matter too. The International Energy Conservation Code (IECC) tells you how much insulation you need for your climate. Cold places need thicker panels or higher R-values. Some codes also want you to stop air leaks between panels. That means you must seal panels well during installation. Codes may require U-factors, which measure total heat loss, not just R-value.   Follow installation rules exactly. Most codes say you must install panels like the manufacturer says. This means using the right fasteners, sealants, and edge details. If you stack panels, stagger the joints so heat can’t sneak through.   Different panel types have special rules. Insulated metal panels (IMPs) have their own code sections now. The IBC added clear rules for IMPs on outside walls. Canada’s National Building Code covers IMPs too, especially for low-rise commercial buildings using polyurethane or PIR cores.   Codes change by location, building type, and height. A warehouse in Florida and a school in Chicago follow different rules. Work with someone who knows the codes. Propanel (propaneltech.com) has 15+ years of experience. They help you pick the right core—PIR for insulation or rock wool for fire safety—and give you the test reports you need. This makes inspections easier.   Building codes aren’t just rules to slow you down. They keep people safe and buildings working well. Learn what applies to your project. Choose panels that meet those rules. Install them right. Doing this now saves you big problems later.  

A sandwich panel has three layers. Two outer skins made of steel, stainless steel, or aluminum. A core in the middle that insulates. The core material depends on your needs. Use polyurethane (PU) or polyisocyanurate (PIR) for good temperature control. They have very low thermal conductivity (around 0.020 W/m·K). Use rock wool if you need fire resistance. It won’t burn and works over 1000°C. EPS is cheap and light but not good with fire or moisture. The panels lock together with tongue-and-groove edges and cam locks. This pulls them tight and seals air and water out. No mortar or bricks needed. They fit together like puzzle pieces for a clean finish.   Where to use them? Almost anywhere. Industrial buildings use them for walls and roofs because they go up fast and keep heat in or out. Warehouses need big insulation, and sandwich panels deliver without costing too much. Cold storage is a top use—meat plants, ice cream warehouses, and pharma cold rooms all need steady temperatures, and these panels do that.   Agricultural buildings use them for animal shelters and crop storage. They are easy to clean and keep animals comfortable. Commercial buildings like malls and supermarkets use them for walls and partitions. Food plants like them because the smooth surfaces don’t hide bacteria and stand up to daily washdowns without rusting.   They also work in unexpected places. Mobile homes and prefab houses use them because they are light but strong. Sports centers, construction offices, and military bases use them for quick, tough buildings. Some panels are made for clean rooms in hospitals or electronics factories where dust is a problem.   Sandwich panels adapt to your needs. Need fire safety? Use rockwool. Need thin walls with strong insulation? Use PIR. Building cheap and temporary? EPS is fine. The steel skins can be painted any color, textured, or coated for extra protection.   Propanel (propaneltech.com) has made PU and PIR panels for over 15 years. We know every project is different. We don’t just sell panels and leave—you get help building something that lasts.  

Cold storage panels are prefabricated materials made for keeping spaces cold. They have two strong outer layers with thick foam inside. The outside is usually steel or aluminum. The inside is foam that blocks heat. The panels fit tightly together with special edges and locks to stop air leaks. You should care because these panels save money. Without them, keeping things cold costs a lot. --First, they save energy. Cold rooms run compressors all day. If walls leak, compressors work harder and bills rise. Good panels have very low heat transfer. A 100mm panel works better than a thick regular wall. --Second, they protect your products. Food, medicine, and flowers need steady cold. These panels keep temperature steady and stop drafts and moisture. --Third, they last long. Steel outer layers resist damage and rust. Foam inside does not soak water or grow mold. Panels are modular, so you can move or add to your cold room later. --Fourth, they stay clean. Smooth surfaces have no cracks for germs. You can clean them with strong chemicals without damage. Some have extra germ protection. --Fifth, they install fast. Traditional building takes weeks. Panels go up in days. That means less downtime and faster profits.   Propanel (propaneltech.com) makes PU and PIR panels that work well in real use. They help you choose the right panel for your needs. Cold storage is not guesswork. Build it right the first time.

Let's start with energy bills. Sandwich panels cut energy use by 2-5% compared to regular walls. That saves you money over 15 to 50 years. They cost less over time because they keep heat in better. Some tests show sandwich panels perform 30-50% better at keeping temperature stable. For places like cold storage, this means lower electric bills every month. Installation costs matter too. Sandwich panels go up fast. They cut labor costs by 40-60% compared to bricks or blocks. No waiting for mortar to dry or bad weather delays. Jobs that took months now take weeks. The faster you finish, the faster you start making money.   Durability is strong with sandwich panels. If you install and care for them right, they last 25-35 years. After 10 years, they still keep 92% of their insulation power. Traditional walls lose insulation when wet or moved. Rock wool cores resist fire and heat. PIR cores resist moisture and keep their value. Galvanized steel stops rust early. You’re buying a wall that works for decades.   Maintenance is simple and cheap. You need to clean, check seals, and inspect edges once a year. It costs about $1.20 to $3.00 per square meter yearly. Doing this saves you 38% of total costs over 20 years. Skipping maintenance can cause early failure and big repair bills. In humid places, neglect can mean repainting or replacing panels in 8-10 years instead of 25. That’s not saving money. It’s risking it.   Resale value is better with sandwich panels. Buyers want energy-efficient, strong buildings. Inspectors notice this too. If you need to move or reuse panels, many can be taken down and used again. Some panels from the 1990s still work well today. This is a smart, long-term investment.  

The Sandwich panels are widely used in food processing factories due to their excellent thermal insulation, good moisture and water resistance, corrosion resistance, and excellent fire resistance.     1. Excellent thermal insulation performance. Generally, the thermal conductivity of PU/PIR sandwich panels is between 0.020 and 0.024 [W/(m·K)], providing good thermal insulation and effectively controlling indoor and outdoor temperatures to ensure food freshness.   2. Seamless splicing during assembly ensures good sealing, reducing the risk of bacteria and mold growth and enabling dust-free workshops.   3. The core material used in sandwich panels has a high closed-cell rate, is non-absorbent, and offers excellent waterproof and moisture-proof performance, ensuring food freshness.   4. The color-coated steel plates used in sandwich panels have high structural strength, strong load-bearing capacity, and good corrosion resistance.   5. Sandwich panels generally have a fire rating of B1 (PIR sandwich panels) or A (rock wool sandwich panels), offering excellent fire resistance and making them more suitable for high-temperature food processing workshops;   6. Sandwich panels are produced in modular form, requiring only on-site installation and splicing, resulting in simple construction, short construction period, less dust, and high cost-effectiveness.

Currently, common sandwich panel include EPS sandwich panel, PU/PIR sandwich panel and rock wool sandwich panel.   Generally speaking, the thicker the sandwich panel, the better the insulation effect. PU/PIR has the best thermal insulation performance, rock wool has the best fire resistance, and EPS has the highest cost performance，but no fireproof.   Due to the different properties of the core material, the application of sandwich panels with different core materials is also different, as detailed below.   Thickness EPS Sandwich Panel PU/PIR Sandwich Panel Rock wool Sandwich panel 50mm Suitable for interior wall partitions in ordinary workshops and factories where insulation requirements are not high, as well as prefabricated houses, temporary houses, temporary buildings on construction sites, and general storage. Suitable for roofs and walls of warehouses at normal temperatures, as well as steel structure exterior walls and roofs. Suitable for interior walls and partitions of ordinary factory buildings with high fire protection requirements and general insulation requirements, as well as walls of simple warehouses and temporary buildings. 75mm Suitable for industrial buildings with no strict temperature requirements, such as general warehouses, logistics warehouses, steel structure workshops, and livestock farms. Suitable for general cold storage and insulation, constant temperature workshops (such as electronics, packaging, light industry, etc.), food processing plants, beverage plants, pharmaceutical and electronics cleanrooms, etc. Suitable for general warehouses, logistics centers, office buildings, workshops, and showrooms. 100mm Suitable for walls and roofs of large factories and warehouses, stadiums, markets, and large steel structure buildings, etc. Suitable for industrial buildings, cold storage (0-5℃), food processing workshops, cold chain warehouses, etc., where high insulation and fire protection requirements are needed. Suitable for high-standard factories, cleanrooms, hospitals, schools, public buildings, etc. 150mm Suitable for buildings with high insulation requirements but limited budgets, such as ordinary factories and warehouses in cold regions. Suitable for high-end constant temperature and humidity workshops, pharmaceutical warehouses, low-temperature cold storage (-18℃), cold chain logistics centers, dairy, meat and seafood processing workshops, etc. Suitable for public buildings with strict fire protection requirements, large warehouses, long-span factories, and buildings with extremely high requirements for thermal insulation/sound insulation, such as concert halls.     In short, 50mm sandwich panels are suitable for interior walls, simple interior partitions, etc.; 75mm sandwich panels are suitable for ordinary factories and warehouses, etc.; 100mm sandwich panels are suitable for food factories and low-temperature cold storage, etc.; and 150mm sandwich panels are suitable for low-temperature cold storage and high-standard buildings, etc.

PU, PIR, and Rock Wool are currently common core materials for sandwich panels. Due to differences in density, thermal insulation performance, water absorption, fire resistance, applicable temperature, and price, their applications also differ.     A detailed comparison is as follows:   Performance Index PU Sandwich Panel PIR Sandwich Panel Rock wool Sandwich panel Thermal Conductivity W/(m·K) 0.022-0.024 0.020-0.022 0.040-0.043 Heat preservation effect High Highest Low Flame-retardant grade B2 B1 A Waterproof Better Better Normal Soundproof Good Good Best Applicable temperature -180℃~+120℃ -180℃~+150℃ -200℃~+700℃           Based on the above, we found that PIR sandwich panels offer the best thermal insulation, followed by PU sandwich panels, with rock wool sandwich panels performing the worst. However, rock wool sandwich panels have the best fire resistance and good sound absorption. Therefore, we recommend PIR sandwich panels for cold storage, PU Sandwich panels for general factories and high-temperature cold chain applications, and rock wool sandwich panels for theaters and large warehouses with high fire resistance and sound insulation requirements.

There are many types of sandwich panels, and common mistakes when choosing industrial sandwich panels include:   1. Focusing solely on price and selecting panels incompatible with the core material. EPS sandwich panels are the cheapest and generally only used in ordinary factories. PU/PIR sandwich panels are chosen for cold storage, while rock wool sandwich panels are chosen for large logistics warehouses.   2.Confusing roofing and wall panels. Wall panels cannot be used directly for roofing. Roofing requires high-strength roofing panels with corrugated peaks to withstand strong winds and rain/snow.   3.Ignoring the density of the core material. Generally, EPS density ranges from 10kg/m³ to 20kg/m³, which can be selected based on different insulation requirements; Rock wool density ranges from 80kg/m³ to 140kg/m³. It is generally not recommended to use less than 90kg/m³ for walls and less than 100kg/m³ for roofs.   4.     Ignoring the thickness requirements of the sandwich panel steel plate The thickness of the top and bottom plates of the sandwich panel can be determined according to the strength requirements of the building. Common thicknesses are 0.4mm to 0.8mm.   5.Ignoring the zinc coating thickness requirements of the sandwich panel Generally, the thicker the zinc coating, the better the corrosion resistance. Industrial buildings typically require AZ100 or AZ150.   6.Ignoring the color coating requirements of the sandwich panel steel plate PE coating can be used in ordinary environments, while PVDF coating can be used in coastal or highly corrosive environments.   7.Incorrect calculation of sandwich panel length, leading to excessive splicing It is recommended to provide CAD drawings. Our technical engineers will calculate the accurate number and length of panels to avoid errors.   8.Ignoring panel load-bearing capacity and span The panel thickness needs to be calculated based on the purlin spacing, load, and wind force of the industrial building to avoid placing orders blindly.