1. Home ›
2. Save Electricity ›
3. Insulation ›
4. Reflective roof top coatings can make a home energy efficient by reducing air conditioning load

Reflective roof top coatings can make a home energy efficient by reducing air conditioning load

Air conditioning is the biggest paint point for most people concerned about their high electricity bills in summers. On Bijli Bachao we get a lot of visitors looking for help on Air Conditioners. In one of our previous posts we mentioned how using ceiling fan with an air conditioner can help. On response to it, some of the visitors said that ceiling fan should not be used with air conditioner because it will push down hot air from the ceiling. Please refer to our article explaining how higher thermostat setting with ceiling fan can give the same comfort at lower electricity consumption. The air conditioning need in a room largely depends on the heat transfer between the room and the outside environment. Heat transfer from roofs is a major component if the roof is exposed to sun. Reading an article on Firstpost, an idea stuck to us and we did our research on the same. And here is the outcome:

Single Family Homes receive a lot of heat from the ceiling

Ceilings can be hot in summers, but not for those living in apartments (not the top floor). But for most single-family homes or apartments at the top of the building, the ceilings face direct sun. Most construction materials are good conductors of heat. That means a room that is directly facing heat from top remains very hot. Thus to cool it, a lot of energy is required by any air conditioner to cool it. If your electricity bills are high and you have rooms that have ceilings that that are exposed to the sun, then getting the right insulation for the ceiling should be your first target. This is especially important for people living in areas that have hot and dry climate, as sun’s radiance levels are very high in such regions.

Reflective Roof-Top Coating can reduce ceiling heat.

Several researches (link and link) have shown that external colors of a building have significant impact on cooling load of the building. A white reflective roof coating can potentially reduce up to 60% of heat coming in from the ceiling. But the results vary in different situations. With various experiments, researchers have found savings to vary from 20% to 60%. Typical rooftop reflective coating paints are made of acrylics, hypalon, neoprene, silicone, urethane and hybrid materials. A quick search on google can provide a list of companies that make and supply reflective rooftop coating paints. Please note that the efficiency of the paint goes down with each passing year, so regular maintenance of the paint is a must to achieve maximum saving.

Other benefits of Rooftop coatings.

Rooftop coatings not only prevent extra heat from entering a house, but have many other benefits too:

• It can increase the life of the roof by 15 years or more.
• Dense cities with lot of swellings in a small area have tendencies of getting heated up significantly. If houses have reflective rooftops, then the amount of heat waves can be reduced.
• In general it can add to greening by reducing waste and saving electricity.

Here is a short video for tips to buy the best air conditioner in India

Source of Information

http://www.environmentaljournal.org/1-3/ujert-1-3-4.pdf

http://www.fsec.ucf.edu/en/publications/html/FSEC-PF-293-95/