Cool roof is cool!

Living in a tropical country like the Philippines with a 90M population and having the worst air pollution rate in the world, will burn you. The weather is becoming unbearable, it's just too hot. The average temperature is 25 C and it could rise to as high as 43 C in a typical summer day. It's like having a sauna bath 24 hours a day. Don't get me wrong, sauna is heaven, but can't have it for 24 hours. No way man.

When I was just 'dreaming' of a house, I setup three must-haves - storage, sunlight and air. Costs of energy bills in the Philippines is just way too expensive and is continuoulsy going up, so if I can avoid using electricity, I will do it. I have a lot of things in my mind like what kind of windows to use, where will they be positioned, but I will share those in a different day. Now, I just want to concentrate in the roof material, because I won't change roof everyday. Whatever will be installed now will be there for the next 20 years.

I'm now requesting for quotations for my roof, and came across a very interesting term - cool roof. That's exactly what I want! I want a roof that's cool and will make our lives cool.

What is a cool roof?



A cool roof reflects and emits the sun's heat back to the sky instead of transferring it to the building below. "Coolness" is measured by two properties, solar reflectance and thermal emittance. Both properties are measured from 0 to 1 and the higher the value, the "cooler" the roof

Why not?

• Lower cooling energy use and lower utility bills (calling Meralco!)


• Lower electricity demand(the maximum energy load, in megawatts, an electric utility experiences to supply customers instantaneously, generally experienced in summer late afternoons as businesses and residences turn up their air conditioners), raised electricity production costs, and a potentially overburdened power grid;


• increased occupant comfort, especially during hot summer monthsreduced air conditioning use, resulting in energy savings typically of 10-30%1


• Decreased roof maintenance because the roof lasts longer

In a nut shell, a cool roof can significantly reduce your cooling energy costs and increase your comfort level by reducing temperature fluctuations inside your home. Average energy savings range from 7%-15% of total cooling costs. It's quite common for Filipinos to include bulk insulation in constructing their homes. This insulation can be entirely replaced by roofing systems that reflect solar radiation and emission to the sky.

How to find out the solar reflectance of the different roofing types?

Solar reflectance or albedo is categorized below. The closer to 1, the cooler it is.

• Highly Reflective Roof - 0.60 - 0.70


• Coloured Paint - 0.15 - 0.35


• Corrugated Roof - 0.10 - 0.15


• White Paint - 0.50 - 0.90


• Tar & Gravel Roof - 0.03 - 0.18


• Red/Brown Tile Roof - 0.10 - 0.35

How will I achieve a cool roof?

• Paint it white or any 'cool' color


• Choose a roofing material with an albedo closest to 1 (as described above)

To know more, visit

http://www.coolroofs.org/