How does thermal insulation and waterproofing acrylic coating achieve "passive cooling" of buildings through high solar reflectivity?
Release Time : 2026-01-07
Against the backdrop of intensifying urban heat island effects and continuously rising building energy consumption, how to reduce building cooling load in a low-investment and sustainable manner has become an important issue in green building technology. Thermal insulation and waterproofing acrylic coating, as a multifunctional material integrating environmental protection, waterproofing, and energy saving, leverages its high solar reflectivity to construct an "invisible insulation layer" on roof and exterior wall surfaces, achieving a "passive cooling" effect without the need for mechanical refrigeration, providing an efficient and economical path for building energy conservation.
1. The Physical Mechanism of Solar Radiation and Building Heating
Approximately 53% of the solar spectrum is infrared radiation, 44% is visible light, and 3% is ultraviolet radiation. Traditional dark-colored roofs have an absorption rate as high as 80%–90%, converting a large amount of solar radiation into heat energy. This causes the surface temperature to reach over 70°C under the summer sun, continuously heating the indoor space through heat conduction, significantly increasing the burden on air conditioning. High-quality thermal insulation and waterproofing acrylic coatings, through their high-reflectivity formula, can directly reflect over 80% of solar radiation back into the atmosphere, significantly reducing heat absorption.
2. Achieving High Reflectivity: Synergistic Optimization of Materials and Structure
The core of thermal insulation and waterproofing acrylic coatings lies in their white or light-colored base combined with a functional filler system. First, high-purity titanium dioxide is used as the main pigment, possessing extremely strong visible light scattering capabilities. Second, special fillers such as hollow ceramic microspheres, hollow glass microspheres, or infrared-reflecting pigments are introduced. These micron-sized particles not only enhance the diffuse reflection effect of the coating but also block some infrared heat radiation penetration. Simultaneously, the continuous and dense film layer formed by high-quality acrylic emulsion ensures uniform distribution and firm coating of the fillers, preventing reflectivity degradation due to aging and peeling. Testing shows that the initial solar reflectivity of high-performance products can reach over 0.85, far exceeding that of ordinary coatings.
3. The Actual Effectiveness of "Passive Cooling": The Temperature Drop Chain from Surface to Interior
Actual measurement data shows that, under the same climatic conditions, the surface temperature of a roof coated with a high-reflectivity acrylic coating is 20–30°C lower than that of an untreated area. This temperature difference is gradually reduced through heat conduction, ultimately lowering the ceiling temperature of the top floor by 5–10°C, significantly improving thermal comfort. Research by the U.S. Department of Energy indicates that large-area application of high-reflectivity roofs can reduce building cooling energy consumption by 10%–30% in summer. The energy-saving benefits are even more pronounced for buildings without air conditioning or with intermittent air conditioning use.
4. Durability Guarantee: Maintaining High Reflectivity Over the Long Term
The decay of reflectivity over time is a major pain point in the industry. Dust accumulation, coating chalking, and mold growth all reduce surface brightness. To address this, advanced acrylic coatings enhance durability through a triple strategy:
- Dense cross-linked structure: High-quality acrylic emulsion forms a high-density cross-linked network after film formation, providing strong resistance to chalking and staining;
- Hydrophobic/self-cleaning technology: Addition of nano-silica and other additives gives the surface a slight hydrophobicity, allowing rainwater to wash away surface dust;
- UV stabilizer: Effectively resists UV aging, prevents yellowing and embrittlement, ensuring a reflectivity of 0.7 or higher over a service life of more than ten years.
5. Environmentally friendly and multifunctional integration: A green solution with multiple benefits in one coating
As a water-based environmentally friendly material, this coating is free of harmful substances such as benzene, formaldehyde, and APEO, meeting green building material standards. Simultaneously, its excellent elastic elongation can cover micro-cracks in the substrate, providing long-lasting waterproofing; its good weather resistance makes it suitable for various substrates such as concrete, metal, and asphalt. In energy-saving renovations of existing buildings, there is no need to demolish the old roof; direct application achieves an integrated upgrade of "waterproofing + heat insulation + energy saving," making construction convenient and cost-effective.
The "passive cooling" capability of thermal insulation and waterproofing acrylic coating is essentially the result of combining the ancient wisdom of "white reflection" with modern materials science. It consumes no energy, yet actively keeps heat away from buildings; though seemingly thin, it bears the heavy responsibility of reducing carbon emissions and improving the living environment. Driven by the dual-carbon goals, this simple yet efficient green technology is becoming an indispensable part of the energy-saving revolution in building facades.
1. The Physical Mechanism of Solar Radiation and Building Heating
Approximately 53% of the solar spectrum is infrared radiation, 44% is visible light, and 3% is ultraviolet radiation. Traditional dark-colored roofs have an absorption rate as high as 80%–90%, converting a large amount of solar radiation into heat energy. This causes the surface temperature to reach over 70°C under the summer sun, continuously heating the indoor space through heat conduction, significantly increasing the burden on air conditioning. High-quality thermal insulation and waterproofing acrylic coatings, through their high-reflectivity formula, can directly reflect over 80% of solar radiation back into the atmosphere, significantly reducing heat absorption.
2. Achieving High Reflectivity: Synergistic Optimization of Materials and Structure
The core of thermal insulation and waterproofing acrylic coatings lies in their white or light-colored base combined with a functional filler system. First, high-purity titanium dioxide is used as the main pigment, possessing extremely strong visible light scattering capabilities. Second, special fillers such as hollow ceramic microspheres, hollow glass microspheres, or infrared-reflecting pigments are introduced. These micron-sized particles not only enhance the diffuse reflection effect of the coating but also block some infrared heat radiation penetration. Simultaneously, the continuous and dense film layer formed by high-quality acrylic emulsion ensures uniform distribution and firm coating of the fillers, preventing reflectivity degradation due to aging and peeling. Testing shows that the initial solar reflectivity of high-performance products can reach over 0.85, far exceeding that of ordinary coatings.
3. The Actual Effectiveness of "Passive Cooling": The Temperature Drop Chain from Surface to Interior
Actual measurement data shows that, under the same climatic conditions, the surface temperature of a roof coated with a high-reflectivity acrylic coating is 20–30°C lower than that of an untreated area. This temperature difference is gradually reduced through heat conduction, ultimately lowering the ceiling temperature of the top floor by 5–10°C, significantly improving thermal comfort. Research by the U.S. Department of Energy indicates that large-area application of high-reflectivity roofs can reduce building cooling energy consumption by 10%–30% in summer. The energy-saving benefits are even more pronounced for buildings without air conditioning or with intermittent air conditioning use.
4. Durability Guarantee: Maintaining High Reflectivity Over the Long Term
The decay of reflectivity over time is a major pain point in the industry. Dust accumulation, coating chalking, and mold growth all reduce surface brightness. To address this, advanced acrylic coatings enhance durability through a triple strategy:
- Dense cross-linked structure: High-quality acrylic emulsion forms a high-density cross-linked network after film formation, providing strong resistance to chalking and staining;
- Hydrophobic/self-cleaning technology: Addition of nano-silica and other additives gives the surface a slight hydrophobicity, allowing rainwater to wash away surface dust;
- UV stabilizer: Effectively resists UV aging, prevents yellowing and embrittlement, ensuring a reflectivity of 0.7 or higher over a service life of more than ten years.
5. Environmentally friendly and multifunctional integration: A green solution with multiple benefits in one coating
As a water-based environmentally friendly material, this coating is free of harmful substances such as benzene, formaldehyde, and APEO, meeting green building material standards. Simultaneously, its excellent elastic elongation can cover micro-cracks in the substrate, providing long-lasting waterproofing; its good weather resistance makes it suitable for various substrates such as concrete, metal, and asphalt. In energy-saving renovations of existing buildings, there is no need to demolish the old roof; direct application achieves an integrated upgrade of "waterproofing + heat insulation + energy saving," making construction convenient and cost-effective.
The "passive cooling" capability of thermal insulation and waterproofing acrylic coating is essentially the result of combining the ancient wisdom of "white reflection" with modern materials science. It consumes no energy, yet actively keeps heat away from buildings; though seemingly thin, it bears the heavy responsibility of reducing carbon emissions and improving the living environment. Driven by the dual-carbon goals, this simple yet efficient green technology is becoming an indispensable part of the energy-saving revolution in building facades.