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For modern construction projects, to use the right building materials is very important, cause buildings require excellent thermal performance--Once the insulation cannot be guaranteed, it may greatly increase energy consumption and operational costs. The sandwich panel—it is usually composed with two metal sheets with insulated core material in between. As is known to all, the sandwich panel is the perfect building material for thermal insulation—so it gives the best insulation performance with structural strength at the same time.   First of all, There are 3 core material of sandwich panel: EPS, rock wool, and PU—each have unique advantages for specific applications. EPS panels provide cost-effective insulation for warehouses and cold storage. Rock wool panels offer superior fire resistance for industrial plants and commercial buildings. PU panels gives the highest thermal efficiency for temperature-sensitive environments. Propanel, just focus on supplying all types of sandwich panels, gives customers the best solution also professional advice at the same time.   Secondly, each core material provides different levels of insulation effectiveness and additional advantages:   Core Material Thermal Conductivity Key Advantages Best Applications EPS 0.032-0.038 W/m·K Lightweight, Cost-effective Warehouses, Distribution Centers Rock Wool 0.035-0.042 W/m·K Fire-resistant, Sound-absorbing Industrial Plants, Public Buildings PU 0.022-0.024 W/m·K High efficiency, Best thermal insulation Cold Storage, Pharmaceutical Facilities The low thermal conductivity values—especially PU's exceptional performance—directly translate to reduced heating and cooling costs, preventing energy loss through walls and roofs.   Thirdly, good installation also ensures insulation - if panels are installed incorrectly - gaps can form - which can lead to the development of cold bridges. Professional installation according to Propanel specifications is important to achieve the advertised R-value and energy savings.  

For a good cold room, using the right insulation system is very important—cause the entire refrigeration efficiency depends on how well the structure keeps cold air inside. Energy loss not only increases electricity consumption but also affects product freshness and storage stability. Insulated sandwich panels are the key solution to keep consistent temperature and reduce energy waste effectively.   The PU sandwich panel is the most common and efficient insulation material used in modern cold storage construction. It is made of two layers of pre-painted steel sheet with a polyurethane (PU) insulated core in between. PU foam has one of the lowest thermal conductivity levels among building materials, meaning it minimizes heat transfer between the inside and outside of the room. Propanel (propaneltech.com) focuses on manufacturing high-performance PU cold room panels, providing customers with stable insulation, long lifespan, and fire-resistant performance at the same time.   Before selecting insulated panels, it is important to match the panel thickness with the target temperature of the cold room. The following table shows the general recommendation: Panel Thickness (mm) Storage Temperature (°C) Typical Application 75 mm +10°C to +5°C Food processing, air-conditioned room 100 mm +5°C to -5°C Chiller room, fruit and vegetable storage 150 mm -5°C to -20°C Frozen meat, dairy storage 200 mm -20°C to -40°C Deep freezer, ice cream cold room   Proper installation and sealing of the PU sandwich panels are equally important. Gaps, uneven joints, or unsealed corners may cause cold air leakage—resulting in continuous energy loss and compressor overload. That’s why Propanel emphasizes professional installation guidance and precise joint systems to ensure the panels fit tightly, keeping the cold room fully sealed.  

For successful international shipping, to use the correct loading method is very important, because sandwich panels need to be carefully packaged, loaded and transported--Once the loading procedure goes wrong, it may cause product damage and financial losses.   First of all, to make sure that the container condition meets transportation standards is the first step. Propanel will conduct a thorough inspection of the container before loading operations begin. If the container floor has protruding nails or sharp objects - the panel surfaces will get scratched easily - this can cause quality problem, finally leading to customer dissatisfaction.   Secondly, packaging and weight distribution calculations must be done before actual loading. It is recommended to use pallets to protect the bottom layer. Never load above the recommended height - otherwise damage may occur - ultimately resulting in the product being damaged and unable to be installed correctly.   Thirdly, security measures should be strictly done before loading. Key points such as angle brackets, protective plates, tension adjustment of straps, and filling of gaps between stacks require experienced workers to handle them according to standard operating procedures. Appropriate inflatable bags or air cushions should fill the empty space and prevent unnecessary movement of the container in rough sea conditions.  

For a good cold room, to use the right way to finish the installation is very important, cause the cold storage room requires excellent sealing performance--Once the sealing performance cannot be guaranteed, It may greatly increase energy loss and spoilage of goods.    The cold storage sandwich panels—it is usually composed with 2-layer pre-painted steel sheet with polyurethane(pu)/polyisocyanurate(pir) insulated core material. As is known to all, the pu/pir is the best thermal insulation building material—so it gives the best cold storage performance with B1 fireproof at the same time.    First of all, ensuring that the quality of the cold storage composite panels is good is the top priority. Propanel, just focus on supplying the pu/pir cold room sandwich panels, give customers the best solution also best price at the same time.   Secondly, ground site preparation and inspection must be done before installation. If the foundation is uneven - the panels won't line up properly - this can cause gaps to appear, ultimately allowing cold air to escape.   Thirdly, node connections are easily handled improperly. Nodes such as column edge connections, wall corner connections, and suspended ceiling points require professional personnel to connect them according to professional instructions. Improper operation can cause cold bridge phenomenon, finally leading to energy loss and damage to the cold storage panels.

The fastest construction time for a standard single-story warehouse using sandwich panels can be reduced to 6 to 14 days. The higher the degree of prefabrication, the simpler the structure, and the more experienced the construction team, the shorter the construction period will be. Conversely, the construction period will be longer accordingly.   Sandwich panels are custom-made products according to the building design dimensions. On-site construction only requires splicing and installation. Compared to traditional concrete structures, this eliminates processes such as masonry and cementing, saving at least 40% of the construction time.   Furthermore, simpler building structures result in faster construction. For example, single-story warehouses without complex spans are the fastest to construct; while multi-story warehouses and workshops, or those requiring provisions for crane beams, will have a construction period of 15-25 days due to the need for additional steel frame structures.   A well-organized and skilled professional construction team can typically install at least 120 square meters of sandwich panels per day, further shortening the construction cycle.

Fire-resistant sandwich panels are composed of two layers of outer panels (usually color-coated galvanized steel, aluminum, or stainless steel) and a layer of fire-resistant core material (such as rock wool, glass wool, or fire-resistant polyurethane) bonded together with a high-strength adhesive.   The outer panels provide strength to the sandwich panel, preventing deformation and collapse at high temperatures. They also protect the core material from direct contact with flames or high-temperature smoke, thus acting as a firebreak.   The core materials, such as rock wool, glass wool, and fire-resistant polyurethane, are inherently non-combustible or flame-retardant. They do not produce open flames or release large amounts of flammable gases when exposed to high temperatures, preventing flames from penetrating the panel and thus preventing the spread of fire.   Different fire-resistant core materials can be selected based on different building fire protection requirements. For industrial buildings (factories, warehouses, etc.), civil buildings (residential buildings, office buildings, etc.), and public buildings (hospitals, shopping malls, amusement parks, etc.), non-combustible rock wool or glass wool sandwich panels should be used. For temporary buildings, polyurethane sandwich panels with flame-retardant properties or EPS sandwich panels with a B1 rating can be selected.  

Sandwich panels can be used in high humidity environments. Sandwich panels are usually constructed of a double-layer steel plate and a layer of core material, which can achieve a good moisture-proof effect by selecting a core material and a steel plate with moisture-proof performance, and by the correct sealing installation method. High humidity environments (such as coastal buildings, food factories, cold storage) need to prevent moisture penetration and corrosion. The steel plate serves as the outer defense line. Galvanized/aluminum zinc coated steel plates (with PVDF or polyester coating, salt spray resistance, rust resistance) are preferred, avoid un-coated steel plates or ordinary plywood (easy to rust, Water-absorbent layer); the core material needs to avoid porous water-absorbent types (such as ordinary EPS foam, untreated rock wool), choose closed-cell or hydrophobic models ——polyurethane (PU, closed-cell rate exceeds 90%, less water absorption), extruded polystyrene (XPS, high density, moisture-proof), this type of core material can prevent moisture from intruding and losing heat preservation or mold, and breeding bacteria.    At the same time, when the sandwich panel is installed, the joints and screw holes of the sandwich panel need to be sealed with weather-resistant sealant (such as silicone glue, butyl tape) to prevent moisture from penetrating through the gaps; 50-100mm ventilation gap can be reserved for enclosed spaces (such as walls) to reduce internal condensation water; stainless steel screws or galvanized screws are selected, and waterproof gaskets are used avoid formation after rusting “tidal channels”. Meanwhile, check the panel coating regularly for breakage, sealant cracking, etc. If small defects are found, repair them promptly to prevent the vulnerability from expanding.   Currently sandwich panels are widely used in various high humidity environments, such as food/aquatic processing plants, cold storage/cold chain warehouses, factory buildings in rainy areas in the south, and underground space/civil air defense engineering with their excellent moisture-proof and impermeable properties, high-quality thermal insulation/insulation, corrosion resistance, and the ability to be installed quickly.

Metal roof panels can usually be installed on top of existing roofs. This “roof installation” scheme is relatively common in industrial plants, warehouses, and renovation of old buildings.   The metal roof panel itself is light in weight, with a conventional weight of 10-30 kg/㎡, which is much lower than the weight of the concrete roof (200-300 kg/㎡), and if the existing roof (such as concrete roof, steel roof) is structurally sound, it can carry additional loads without substantial reinforcement. And different corresponding solutions can be selected for different original roofs: the concrete roof is fixed with galvanized C-shaped steel purlins + expansion bolts, the old metal roof is connected with aluminum alloy keels (lightweight) + waterproof gasket screws, and the wooden roof is anti-corrosion Purlins can avoid damaging the original structure and are flexible.   If the existing roof waterproofing layer is intact and only slightly defective, it can be installed directly after cleaning. There is no need to remove the old roof, eliminating the cost of demolition and garbage removal. The construction period is more than 50% shorter than “demolition and reconstruction”. It is suitable for buildings that need to be quickly restored to use (such as factories and warehouses), with low cost and short construction period. At the same time, the metal roof panel also protects the original roof。At the same time, it can isolate rain, snow, and ultraviolet rays, extend the service life of the old roof base (such as concrete and wooden keels), and reduce the frequency of repair of the original roof. And General metal roof panels have low thermal conductivity, good thermal insulation performance, good fire protection performance, high safety factor, fire protection, wind resistance, and corrosion resistance (such as aluminum-magnesium-manganese plates, galvanized color steel plates), which can improve the overall disaster resistance of the roof. ability.   Overall, if the original roof structure is intact and the load-bearing capacity is sufficient, the installation of metal roof panels is a cost-effective renovation plan.

Good Quality Control Sandwich panel is the best choice for factories and warehouses in many industries. The panel is combined by two metal sheets with rock wool or eps/pu, pir foam in the middle. The production uses high-pressure combination process that makes panels strong enough for heavy industrial use. We have a strict testing of each panel before packing and loading.   Good Fire-Proof Performance Rock wool sandwich panel has a very good fire proof performance for industrial buildings. With 50mm thickness rock wool core, it will have 60 minutes of fireproof time. While the thickness increases to 100mm, and you get 120 minutes of fireproof time. This kind of sandwich panel will give people enough time to escape while on a fire.   Good Noise Control There is lots of loud machinery and equipment noise at some Industrial sites. As professional acoustic sandwich panel supplier, Propanel’s rock wool sandwich panels can keep down noise levels obviously. Rock wool noise-absorbing sandwich panel can effectively absorb noise and provide workers with a healthier working environment.   Energy-saving and Cost-saving  Although the initial cost may seem high, sandwich panel saves money in the long run. It’s insulation advantages reduce energy costs. The panel has anti-rust, anti-mold, and anti-pest performance with only common treatment. Most panels have 20 to 30 years life time and only needs basic cleaning work. Quick installation of less construction work also saves money for the project.

Sandwich panels can be customized for design and size to meet exact project specs for sure.    Common sandwich panel’s thickness varies from 30mm to 300mm, and lengths from 400mm to 12000mm. Factories use automated cutting for precision during production. Quality checks test thickness fittings and core density to ensure standards. While the core materials of sandwich panel also allow custom options: EPS for light weight, rock wool/glass wool for sound control and fire safety, and PU/PIR for better insulation. As professional rock wool panel china manufacturer as well as china cold storage panel manufacturer—PROPANEL, is engaged to give the best products to customer.   The metal surface layers include steel sheet, aluminum plate, or stainless-steel sheet... Inspections verify material bonds and fire ratings with lab tests.   The paint types of metal surface offer customization: PE for basic protection, HDP for higher durability, SMP for higher weather resistance, and PVDF for longer color life. Panels go through roller coating in production for even finish. This step follows strict color matching. Final quality detection uses visual and machine scans to confirm paint adhesion and thickness.   Special shapes sandwich panels like triangles or circles satisfy unique needs. Molds shape panels during manufacturing for custom fits. These handles curved or angled designs. Production ends with load tests and seal checks to confirm strength. Such special quality control ensures panels perform in all kinds of buildings’ roofs or walls.

Discover PROPANEL Sandwich Metal Roofing Systems PROPANEL sandwich metal roofing systems are a good choice for Large Projects. Made with a strong metal exterior and an insulating core, these panels resist extreme weather like heavy rain or strong winds. Whether it’s a warehouse or a factory project, PROPANEL gives a long-lasting solution that you can wait for.   Why Choose Sandwich Panels for Your Roof? Sandwich panels from PROPANEL bring more than just strength. The design has better heat insulation, making buildings super energy-efficient. This means lower heating and cooling bills for your building. The insulation also cuts down noise, perfect for busy industrial spaces. With PROPANEL, you get a roof that saves money and keeps things comfortable inside.   Easy Installation with PROPANEL One big advantage of PROPANEL sandwich metal roofing is how simple it is to install. The lightweight panels fit together quickly, saving time on big projects. No need for professional tools or long times—contractors will love how fast they can get the job done. PROPANEL’s prefab building material system means your roof is up and ready without any trouble.   PROPANEL: Built for Efficiency and Strength What makes PROPANEL so good for the building? It’s the combination of insulation and easy installation (prefabricated steel building materials). These sandwich roof panels keep buildings cooler in summer and warmer in winter, giving strong against for extreme weather. From storage rooms to large workshops, PROPANEL offers a reliable, low-maintenance roofing option that both better performance and value.

Compared with old-style single metal roof system’s definitely noisy, the modern insulated sandwich metal roof panels stepping in – they're right one that replace noisy metal into the quiet protection.    The Secret: Insulated Core Technology The key is what inside the middle of the sandwich panel. Each core material tackles noise differently while delivering bonus benefits.  ·Rock wool cores sandwich roof panels are the acoustic champions – those dense mineral fibers absorb sound waves, cutting rain noise by up to 40dB while providing Class A fire protection.  ·EPS cores sandwich roof panels offer the budget-friendly solution. Lightweight and affordable, reduce noise compared to single metal roof.  ·Then there's PU sandwich roof panels– the premium performer. With superior density and 0.02-0.024 W/(m·K) thermal values. The closed-cell structure blocks both sound transmission and heat transfer.   Real-World Sound Performance Single metal roofs noise is 55-60 DB during heavy rain – that's conversation-level noise disrupting sleep. Propanel's insulated metal sandwich panels drop this to 25-30 DB – quieter than a whisper!   Why Propanel Delivers Quiet Comfort Propanel insulated metal roof sandwich panels means to use noise-reduction technology. These panels install quickly while creating peaceful indoor environments that last decades. The quickly insulation stops both sound and energy waste.