If you are in the market to put a new roof on your home, you know there are a lot of options on the market to choose from. While you may first be drawn to your choice of materials based on how they look, you will also want to choose materials that will be energy efficient. By choosing the right materials, you will be able to reduce the amount of heat your home absorbs, which will allow you to reduce your energy consumption. One of the options that you may want to consider are cool roofing materials. Not only will they help you achieve your energy reduction goals, but they will also look good and save you money while they do it.
What Is A Cool Roof?
Any time you go outside on a hot sunny day, you quickly feel the hot rays of the sun. The longer you are outside, the warmer you become. Your roof is no different, with the exception that it constantly remains in the sun. To remain cool it needs special materials that will reflect the sun's rays, as well as reduce the amount of heat that your roof will absorb. You will find these materials in a cool roof.
Cool roofing materials offer two different measurements to determine the potential coolness of your roof. These two measurements are:
- Solar Reflectance - This is the amount of sunlight that is reflected from your roof and back into the atmosphere.
- Thermal Emittance - This is the ability of the roof's surface to radiate absorbed heat.
Both of these measurements are evaluated on a scale from 0 - 1 with the higher number being the best choice. Another method for evaluating coolness is a combination of both of these measurements. This is called the Solar Reflectance Index (SRI).
SRI uses a different scale of measurement, with the perfect value coming in at approximately 122. You will never find a roofing material with a rating this high, since stainless steel only has an SRI of 112.
What Types Of Roofing Materials Can Be Cool?
Unlike other types of roofs in which you have to choose between shingles, tiles, or various types of metals, you can find cool roofing materials in a wide range of roofing products. Some of these products include:
Highly reflective types of roofing paints - Although metal roofing materials make great solar reflectors, they tend to absorb and not emit thermal heat. By using a highly reflective roofing paint, you can increase the amount of solar heat that is reflected, as well as the amount that is emitted. This will allow your metal roofing materials to become cool.
Highly reflective roofing shingles or tiles - Many roofing tiles are constructed from light colored glazed slate, clay, or concrete. Although these materials are naturally reflective, additional surface treatments applied to these materials can increase their natural properties, which in turn will allow them to qualify as cool materials.
There are also a wide variety of shingles that have been created and treated with special coatings that allow them to exhibit cool properties. While many of these shingles used to be only available in white, or other light colors, more color choices have arrived on the market.
Special roofing membranes - These are often white or light colored reflective bituminous waterproofing membranes that will offer you the advantages of waterproofing your roof along with creating a cool roof. These are most commonly applied under other roofing materials but may be used as an outer coating on flat roofs.
Special roofing coatings - Cool roof coatings can be found in two different types. These are factory applied and field applied. As the name implies, coatings that are factory applied are spread over the roofing materials prior to the materials coming onto the market. Those that are field applied can be spread over the roofing materials on-site and can be used on a new roof or on an existing roof.
These are only a few of the materials available to assist you in creating a cool roof. As technology changes you will see more choices arrive on the market. Before you commit to another roofing material, do your research and see if a cool roof would work for you. Not only will these roofs help you save money by reducing your energy cost, there may even be rebates available in your area that will help to offset the cost of applying your roof. You can find a list of some of the current rebates available here, but there may be others available through rebates found through your state or local energy company.
For more options and information and more about this topic, contact professional roofing contractors in your area.