What is a Cool Roof?
A cool roof is a roofing system that has been designed or treated to reflect more sunlight and absorb less heat than traditional roofs. This reduces the amount of heat transferred from the sun into the building below, resulting in lower indoor temperatures and reduced energy costs for cooling. Cool roofs can also be made from materials that have a high solar reflectance index, meaning they reflect sunlight and absorb less heat. In some cases, cool roofs may also be designed or treated to have a higher emissivity rating, allowing them to radiate heat away from the building more efficiently. Cool roof products can vary greatly in terms of material composition, performance characteristics, and cost. Detailed information on how cool roofs can reduce energy costs can be found on the Environmental Protection Agency’s website. In addition, many states and municipalities offer incentives for homeowners to install cool roofs to reduce their environmental impact.Types of Cool Roofs
Cool roofs come in a variety of colors, textures, and materials. They are typically made from reflective materials or coatings that reflect sunlight and absorb less heat than traditional roofs. Here are a few of the most common types of cool roofs available:- Single-ply membranes – Single-ply membranes are usually made from synthetic rubber compounds, such as ethylene propylene diene monomer (EPDM), or other materials like thermoplastic polyolefin (TPO). These roofs are often installed in large strips and then sealed together with adhesive or mechanical fasteners. They’re lightweight, flexible, and resistant to weather and ultraviolet light.
- Metal roofs – Metal roofs are long-lasting and durable, making them a great option for any home or commercial building. They come in a variety of colors and textures, plus they reflect sunlight better than other materials. The downside is that metal can be noisy when it rains or hails.
- Built-up roofs (BUR) – BUR roofs are constructed from layers of asphalt and a reinforcing fabric, such as glass fiber. They’re usually covered with gravel or stone chips to protect the asphalt. BUR roofs can last up to 20 years and are often used in commercial buildings due to their fire-resistant properties.
- Modified bitumen membranes – Modified bitumen membranes are a type of roofing material used on low-slope roofs. It is made from asphalt and other materials such as rubber or plastic that have been modified to make them more durable and waterproof.
- Spray foam roofs – Spray foam roofs can deliver high levels of insulation and air-sealing, making them an effective solution for a cool roof. The foam layer forms a continuous barrier against outside elements and provides an R-value that helps to lower energy bills in the summer months. Moreover, spray foam roofs are lightweight, so they don’t require additional reinforcement of the roof structure.
- Photovoltaic roof systems – Photovoltaic (PV) roof systems are becoming increasingly popular as a cool roof solution. PV roofs are highly reflective and designed to convert sunlight into electricity, which can be used to power a building or home. The PV roof systems can also generate additional energy savings by providing shade and reducing the amount of heat absorbed into the building.