Roofing granules are UV-resistant and reflect sunlight to increase your roof’s water resistance. They also protect your asphalt shingles from freezing and enhance the water resistance of your roof. Here’s a guide on how to apply roofing granules. Before you begin, make sure you have a bare surface that is clean and dry. Apply a layer of primer before applying a base coat.
Roofing granules are UV-resistant
It is very important to choose a roofing granule that is UV-resistant, and this is often determined by the base rock. Some of the materials used for roofing should be highly reflective, while others should have very low solar reflectance. Roofing granules should be rounded or cubical in shape, not flat or elongated. Round granules are better because they have higher granule loading on the coated surface of a roof panel, and cubicles are more efficient at minimizing shading.
Roofing granules are UV resistant by reflecting incident radiation. In addition, they are typically colored with organic or inorganic pigments. The color intensity depends on the type of pigment and the amount used. During manufacturing, granules are subject to rigorous tests for UV-resistance and durability. This includes color fixation tests that ensure that the pigmentation adheres to the stone granule.
3M is one of the largest manufacturers of granules for shingles. Founded in 1929, 3M acquired Wausau Abrasives and entered the asphalt granules market in the 1970s. In the 1980s, the company patented an algae-resistant granule that was called Scotchguard. It marketed 3M Cool Roofing Granules in 2006.
Roofing granules with UV coating layers can include an inert mineral core particle and a UV coating layer that encapsulates the mineral particles. The UV coating layer should cover a significant portion of the surface area of the particles and provide adequate UV opacity. Moreover, roofing granules with UV-resistant coatings can be used for bituminous roofing products.
Roofing granules are made of crushed stone or minerals. They improve the performance of shingles and help them last longer. Their UV-resistant coatings are also excellent at reflecting sunlight and infrared radiation. This is important in hot climates, as reflective granules keep the home cooler. These factors make it possible to choose a roofing granule that offers UV-protection.
The present invention provides a method for preparing roofing granules that are near infrared reflective and have high opacity to solar ultraviolet radiation. These granules can be made from conventional coating pigments, and are made with a high-temperature calcination process. Ferro Corporation of Cleveland, Ohio, produces these granules by utilizing high-temperature calcinations.
They reflect sunlight
Solar reflective roofing granules are generally white in color and can be made from conventional coating pigments. They should have a particle size of less than #425 mesh and a percentage of aluminum oxide that is more than 90 percent. They should also have a concentration near the outer surface of the granule. Here are some common types of reflective roofing granules. The type of roofing granule you select depends on how much reflective power you want to achieve.
Typical industrial-grade roofing granules have limited coating coverage and a patchy surface. This means that solar heat will pass through the mineral particles and will be absorbed in part. Because crushed minerals have a high surface roughness, they tend to absorb significant amounts of solar heat. Additionally, they contribute to the “heat island” effect. Moreover, improving solar reflectance is more challenging when the color space is darker.
The primary roofing granules of the present invention will have a plate-like or flat shape. This allows for a high total surface reflectance contribution as well as an enhanced spectral reflectance. Conventional roofing granules typically have irregular shapes, which result in significant losses in solar heat reflectance. By comparison, solar heat-reflective roofing granules are coated with a solar heat-reflective material.
Solar reflective granules can be manufactured with a similar color aesthetic to standard non-solar reflective shingle granules. These shingles can closely match the color of traditional shingles while meeting the ENERGY STAR(r) requirements for residential cool roof systems. If you’re planning to install solar reflective roofing granules, it may be wise to seek the advice of a professional roofing contractor.
Roofing granules can be made from a variety of mineral sources. Typically, they involve quarrying or crushing the rock and then drying, coloring and curing it. Typical solar reflectance is about 70 percent. Solar reflectance can also be increased by applying a white pigmented latex coating. Various manufacturers have developed products with similar solar reflectance as conventional roofing granules.
They protect asphalt shingles from freezing
Applied to an asphalt shingle roof, granules are graded particles of material that prevents the shingles from absorbing UV rays and weathering. They also look better on a roof than black asphalt. As shingles age, their granules tend to shed, resulting in bare or shiny spots. If this happens, it’s time for a new roof.
As asphalt shingle roofs age, they lose granules. While this is inevitable, excessive granule loss can lead to a bald patch on the roof. The granules also may collect in the gutter system and erode the roof’s integrity. For these reasons, you should have your shingle roof inspected by a professional annually.
When it comes to applying roofing granules to protect asphalt roofs, it’s important to know what each granule does and why it’s needed. Glass and organic shingles have a unique set of properties, so it’s vital to read the specs before purchasing them. Glass shingles must comply with a specific set of standards. Likewise, asphalt shingles and roof coverings that are coated with asphalt are more resistant to freezing temperatures.
In freezing climates, a shingle’s body is exposed to direct sunlight. The exposed shingle substrate begins to absorb water, causing a dripping problem. Aside from breaking individual shingles, they may also suffer from a freeze-thaw cycle. As a result, nails may break or become looser. If granules are applied to asphalt shingles, a contractor should apply them using asphaltic cement that’s recommended by the manufacturer.
Although the ENERGY STAR certification does not require asphalt shingles to have a thermal emittance value, they’re often listed on specification sheets. When choosing products based on thermal emittance, consider your climate. In sunny climates, high thermal emittance might be a better choice. In colder climates, a lower SRI rating will do.
They enhance roof’s water resistance
Roofing granules are made from ceramics and minerals that are resistant to ultraviolet light. These granules enhance water resistance and shingle performance. Additionally, the reflective coating of granules helps in lowering the interior temperature of the home. In areas with hot summers and cold winters, this can reduce the heat gain and thus lower utility bills.
When applying a waterproofing membrane on a roof, its elongation must be sufficient to accommodate any movement in the structure. For example, if a building has two slopes that meet in a “hip,” the shingles will be insufficiently protected and water will seep in, causing the roof to leak. Furthermore, an improperly installed roof valley can cause a major roof leak.
However, when applying granules, roofers look for signs of significant granular loss. To determine whether the granule loss is due to hail, foot traffic, or other factors, the roof should be inspected by a professional. The roofer can assess the problem and apply the appropriate solution. In the event of substantial granular loss, it may be necessary to replace the entire roof.
Bituminous waterproofing membranes need to be adhered firmly to the surface of the roof. Self-adhesive bituminous membranes can be applied with a blowtorch and are best if firmly laid over filler material. In order to maximize the water resistant ability of the bitumen waterproofing membrane, it should have a high elongation percentage.