How the Cool paint on roof works/(Heat Reflective paint) ?

Heat Reflective paint/Cool paint is a Heat Reflective Paint and this paint  has been designed to reflect more sunlight and absorb less heat than a standard roof.  Its application reduces roof temperature and correspondingly reduces room temperature. In the case of air-conditioned spaces, the power consumption is reduced due to the lowered temperature gradient across the slab. 

Just as wearing light-colored clothing can help keep you cool on a sunny day, cool paint material that is designed to reflect more sunlight and absorb less heat than a standard roof.
Cool Paint  is made of highly reflective type of paint by emissivity aqueous coating based on acrylic- resins. It is an eco-friendly paint which upon application to cementaceous, asbestos or MS roofing, increases the emissivity of that surface, which results in reflection of heat energy.
Apart from this the non-conductive properties it also provides insulative effectiveness through its uniformity.

Application of Cool Paint:

1. Cleaned ores to be washed with water, Bleaching Powder (If Required)
2. Stir the paint thoroughly before each use.
3. Apply first coat with brush on the cleaned & washed surface.
4. Apply second coat after o gap of minimum 3 to 4 hours.
5. Ensure that the coated area does not come in contact with water for atleast 2 hours.
6. After completion of full coating, it should be allowed to cure.
7. It can be applied by spraying, roller or brush, making it a very simple-labour product that is easy to apply and can replace bulky conventional and standard insulation materials, and can enhance or replace those existing materials.

Benefits of cool paint:

• Ultraviolet and Infrared Resistant – Continuous rejection of solar heat resulting in drastic reduction of roof heat. Increase in temperature due to heat radiation from the roof is stopped, keeping the coated area comfortable even in peak summer afternoons.
• Reflecting UV and IR rays back to the atmosphere.
• Eliminates the necessity for false ceiling.
• Can be coated on any roofing material / side walls.
• Prevents Island effect.
• Helps in reducing the emission of greenhouse gasses and global warming.
• In warm, moist locations, cool roof surfaces can be more susceptible to algae or mould growth than hot roofs. Some roof coatings include special chemicals that prevent mould or algae growth for a few years.
• Contains no solvents, cleans up with water. No toxic substance included.

Selection of Good Cool Paint:

1. Good cool paint has SRI Value 121-123
   Solar Reflectance Index (SRI): Incorporates both solar reflectance and thermal emissivity in a single value. SRI measures the roof’s ability to reject solar heat. The good cool paint has SRI value of 122.
2. VOC ( volatile organic compounds) for cool paint should be between 1.2- 1.34gm per liter.
3. It should not have any type of solvents and zero toxic substances.
4. A good cool paint should be waterproof, dustproof and resistant to fungus formation during monsoon.