Regular application of driveway sealant is essential for a driveway. Asphalt or blacktop driveways, which are the most common in homes everywhere, need to be sealed every few years. A good quality sealant will stand to wear and tear for several years. So if you use a high grade sealant, you will not find the need to reseal your driveway for 6 or 7 years. Driveway sealants are classified into 3 types: asphalt sealants, coal tar based sealants and acrylic sealants.
Asphalt Sealants
These sealants are quite popular on the market. Composed of asphalt, this is the simplest sealant solution available. Asphalt sealants are considered environmentally safe. They have very low levels of Volatile Organic Compounds (VOCs), which makes them relatively odor-free.
Asphalt sealants have a few drawbacks as well. They do not stand up to the elements very well and in most cases a reapplication of sealant may be needed after 3 years or so. Because asphalt sealants are petroleum based, they are sensitive to gasoline, kerosene and motor oil, which act as solvents on the asphalt. As a result, exposure to such materials will degrade the sealant quickly and result in stains and cracks. Asphalt sealants are prone to color fading, because they do not have a high level of resistance against ultraviolet rays. However, newer products on the market seek to overcome these shortcomings with the addition of polymers that enhance resistance to sunlight, heat, gasoline and motor oil.
Coal Tar Based Sealants
Made from coal tar, these sealants are more popular because of the high durability and resistance to fading, among other properties. Coal tar sealants have a high level of ultraviolet protection, which makes them resistant to color fading. Your driveway will remain black after several years of exposure to the elements. These sealants are also resistant to damage from gasoline and brake or transmission fluids. Coal tar sealants are more durable and resistant to daily wear and tear. The resistant to moisture is better as compared to asphalt sealants.
Coal tar sealants emit VOCs, which results in the emanation of odors during the sealing process. These products are not considered very environmentally friendly. There is also the risk of burning skin on contact, as these products are skin irritants.
Acrylic Sealants
Composed of polymers and acrylic emulsion, these sealants are totally synthetic. They have better performance characteristics that asphalt or coal tar sealants. Acrylic sealants repel water, resist sunlight and are affected by solvents. Many of these solvents even come with a 10 year warranty.
Choosing the Right Sealant
If you want a long-lasting sealant, go with acrylic or coal tar based sealant. If you want an environmentally friendly product, choose asphalt sealant. You must, however, be prepared for frequent reapplication. In general, the thickness of a sealant and the warranty period provided by the manufacturer are good indicators of quality. Never apply multiple layers of sealant on a driveway, especially if it is thick. Doing so will cause peeling and deformation. The best time to seal your driveway is during the hotter days of summer.
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