What are the advantages and disadvantages of polyurethane rigid foam insulation decorative integrated panels?

Advantages of polyurethane rigid foam insulation and decorative integrated panels:

Efficient thermal insulation: Polyurethane hard foam has a low thermal conductivity (0.024 - 0.040W/m·K), which is one of the smallest thermal conductivity coefficients among industrial thermal insulation materials. Under the same thermal insulation requirements, the thickness of the building's outer envelope can be reduced and the indoor usable area can be increased. For example, compared with traditional indoor insulation materials, it can save about 2% of indoor area.

Excellent waterproof and moisture-proof performance: the closed cell rate is more than 90%, which is a hydrophobic material. It will not increase the thermal conductivity due to moisture absorption. The wall will not seep water. The water absorption rate is ≤3%. It can effectively prevent moisture intrusion and improve the humidity stability of walls and indoors.

Fire retardant and high temperature resistance: After adding flame retardant, it becomes a flame retardant self-extinguishing material with a softening point of more than 250 degrees Celsius. When burning, carbon deposits are formed on the surface, which can effectively isolate the spread of flames and does not produce harmful gases at high temperatures.

Rich decorative effects: The surface layer is mostly made of metal materials with rich colors, which can meet market customization needs, such as brick patterns, elastic paint patterns, wood patterns, cultural stones, marble patterns, corrugated patterns, etc. It not only maintains heat insulation, but also greatly improves the exterior wall decoration effect.

The construction is convenient and efficient: factory prefabrication is used to integrate the insulation and decorative functions. The construction is mainly based on the combination of bonding mortar pasting and mechanical anchoring. The density of anchor bolts reaches 6-8/㎡, which avoids wet work contamination. There is no need to deal with the old base layer during installation. The construction cycle is short and the efficiency is high. For example, in new building energy-saving projects and existing building renovations, the construction phase hardly affects normal offices and residences, there are no environmental problems caused by wet work such as cement, and the construction time is short and efficient.

Stable and reliable quality: High degree of factoryization makes quality control easier. It can effectively solve the problems of cracks, falling off and cracking that are easy to occur in insulation construction. The average life of the rigid foam polyurethane insulation structure can reach more than 30 years under normal use and maintenance conditions.

Lightweight, high-strength, safe and durable: with the same area and size, the weight is less than one-fifth of stone. The base wall has a high load-bearing safety factor, and the exterior surface has good strength, is resistant to acid, alkali and oil stains, is beautiful, and has good self-cleaning performance.

High overall cost performance: Although the unit price of rigid polyurethane foam is higher than that of other traditional insulation materials, the increased cost will be offset by a significant reduction in heating and cooling costs, and long-term maintenance costs are extremely low.

Disadvantages of polyurethane rigid foam insulation and decorative integrated panels:

Restricted by environmental conditions: the temperature during construction must not be lower than 5°C or higher than 40°C, the wind force must not be greater than level 3, and the relative air humidity should be less than 70%. In unfavorable climate conditions, poor foaming will have an irreparable impact on the future durability of the insulation system.

On-site construction is complex: The polyurethane system requires on-site machine spraying, which involves the coordination of a series of issues such as wires, cables, power supplies, scaffolding, and personnel, which brings many obstacles to the simplicity of construction. When the number of machines is limited, the construction efficiency will be affected, and when there is a lot of scaffolding construction, it is not easy to achieve continuity in details such as each layer and corners, and these node locations are precisely the key to ensuring the quality of the external wall insulation system.

Water vapor evaporation obstacles: Polyurethane materials are foamed closed-cell systems, and the use of on-site integral spraying construction will inevitably cause obstacles to the evaporation of water vapor in new walls in the future, resulting in a series of problems such as bulging, cracking, and leakage.

Poor later repairability: For the wall pipe holes, air-conditioning holes, etc. or holes that are reserved for the building at a later stage, the 'proud' on-site overall construction of polyurethane exactly reflects its poor later repairability and repairability. It is unimaginable that after the wall scaffolding is removed, the spraying machine still has to be moved to repair various parts and heights.

Flatness is difficult to control: The foaming process of polyurethane insulation boards is irregular, so it is completely impossible to obtain a smooth and flat insulation layer. However, the EPS system can achieve good flatness through grinding and trimming, thus laying a good foundation for the later finishing layer coating.

Insufficient bonding strength of the base layer: The polyurethane system needs to rely on the adhesion of the interface agent to the base layer and then to the interface agent. This fully illustrates the lack of direct bonding strength of the polyurethane material to the base layer during the foaming process. Interface agent is a thin coating material, which is relied upon for both the connection of the base layer and the application of anti-cracking putty. This shows that the polyurethane insulation system is divided into many layers, and the integrity and bonding strength of the system are extremely affected.

Thickness limitation: The maximum thickness of polyurethane can only reach 6cm, while EPS can reach 60cm. If a polyurethane insulation system is used, it is impossible to make a variety of decorative lines that meet the designer's requirements.

The height of pasted tiles is limited: Most areas stipulate that the height of polyurethane system wall pasted tiles is limited to low-rise buildings, while the EPS system has relatively more space.

Hidden dangers in node treatment: There is no flip-up net during the construction of the polyurethane system, which embeds hidden dangers for cracking and leakage of the wall in the future. The EPS system uses the overwrapped mesh construction method at key nodes such as cornices, deformation joints, balconies, and awnings, which really plays a role in waterproofing and preventing cracking of the system.

Difficulties in corner processing: When the polyurethane system is used to treat the corners of walls, due to the irregularity of foaming, it is impossible to achieve good right angles in the insulation layer. The only way to compensate is by applying putty in uneven thicknesses. This brings great hidden dangers to the corner's crack resistance, impact resistance, and wind pressure resistance.

Material aging problem: The aging phenomenon of polyurethane insulation board materials is greatly affected by ultraviolet rays and temperature, so it is easy to cause brittle cracks in parts such as window openings that are accidentally exposed to the outside world. What’s more worth mentioning is that after the polyurethane insulation layer is foamed and sprayed on the base of the wall, it may have to be left aside for several days before applying the protective layer due to factors such as climate, division of labor, and construction progress. During this period, the polyurethane plastic will become brittle and hard, posing hidden dangers to the ductility and service life of the insulation system in the future.