An asphalt overlay is an additional layer of asphalt that covers imperfections in existing asphalt. Asphalt overlays are commonly applied to driveways, parking lots, and pavement that have minor damage like light cracking, mild deterioration, or slightly sunken areas. The process of overlaying asphalt commonly includes a leveling out of the old asphalt's shape, ensuring a smooth, even surface on which to add additional layers.
After the minor imperfections in the original asphalt have been filled in, butt joints are typically utilized to ensure the base layer remains level. This guarantees the asphalt overlay will match the height of doorways, garage thresholds, roads, sidewalks, and curbs. A special primer is then applied to the surface; this primer acts as the glue that secures the second layer of asphalt to the first. At this point, crushed stone may be necessary to further ensure a level asphalt overlay design. Once the stone has been compressed and graded, the paving begins. Asphalt concrete overlay is poured over the original layer, primer, and crushed stone. The butt joints make certain the asphalt meets the perimeters of the area and remains level. Once it is dried, the overlay has a sleek, smooth appearance that is free of defects.
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When preparing to administer an asphalt concrete overlay, it is important to bear a couple of considerations in mind. First, it is important that the damage on the original layer not be too deep. If it is, the second layer will simply seep into the cracks and indentations of the foundation, and the problem will remain unsolved. Second, drainage of the area to be paved should be considered. All surfaces need to have runoff for excess water, and, if this step is overlooked, water could rush unchecked into homes, garages, yards, and streets.
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There are special products currently on the market that are specifically designed to enhance the appearance of an asphalt overlay. One such product is a mat-like covering that is installed over the original layer before the asphalt pavement overlay is put down. Made of special fibers, this layer is designed to absorb excess water and maintain a smooth appearance, prolonging the life and appearance of the overlay.
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While an asphalt overlay may be necessary to repair a damaged surface, there are ways to avoid having to invest in this process in the first place. Maintaining a level surface by regularly filling in cracks and potholes is one of the most important. Guaranteeing that proper drainage areas are installed, or creating additional exit routes for excess water, also helps to avoid the need for an overlay in the future.