- What is the solar reflectance index?
Solar reflectance index (or SRI) is something that is used to measure how hot a surface can become when it is exposed to direct sunlight. Certain roofing systems sequester more heat than others, especially if they have a high SRI. This index measures both how much heat is emitted from the roof and how much is reflected away from the surface.
SRI is measured on a scale of 100 to zero, with a very reflective white roof being a 100 and a black surface (which absorbs the most heat) being a zero. Those with the highest SRI are coolest, and those with the lowest SRIs tend to be the hottest.
Why should I care about the SRI of my roofing material?
A high SRI means a cool roof that reflects sunlight and absorbs a minimal amount of heat from the sun. This is ideal, because less warmth absorbed means lower surface temperatures. Lower surface temperatures are better for the environment, especially in terms of global warming and the ozone layer. In cities, an excess of heat-absorbing building materials and roofing can cause a "heat island" effect, where areas are a few degrees warmer than surrounding suburban areas. This can cause damage to the environment.
Cool roofing keeps heat off of buildings and then protects the ozone layer. In addition, you spend less money on cooling and air conditioning needs when your roofing naturally reflects warmth. Keeping your building comfortable to lod in not only creates a pleasant environment for those inside, but it also preserves the energy needed to adjust temperatures accordingly.
Many roofing materials with high SRIs are also recyclable and easy to install without the use of caustic and toxic chemicals. This makes them much more beneficial for the environment than many conventional types of roofing (such as shingle).
What kind of roof offers a high SRI?
Luckily, there are lots of options when it comes to finding roofing that offers a high SRI. PVC roofing can be manufactured so that it offers a very high SRI. PVC roofing is not only a good pick for energy savings and environmental stewardship, but it is also reliably inexpensive and can be purchased in a variety of different looks to match your particular building needs.
To find out more about SRI and roofing, go online and search for manufacturers of environmentally sustainable, cool roofing systems.