TIPS FOR A BETTER ASPHALT OVERLAY
Before applying an overlay, repair damaged or distressed areas in the existing pavement.
A pavement overlay is the application of a layer of bituminous paving to an existing paved surface. This adds structural capacity and smoothness of ride all while improving the exterior appearance of your property. Other benefits include enhanced safety because tripping hazards are minimized, improved dust control, and reduced maintenance time.
When an asphalt pavement surface deteriorates to the point of needing repair, an asphalt overlay is an effective solution. The thickness of an overlay is typically 1 1/2 to 3 inches. The amounts of traffic, existing pavement condition, as well as an individual customer’s needs are considered in determining thickness. The existing asphalt surface may be milled if grades need to be maintained or altered. Milling is a process by which a machine is used to plane the pavement surface to an appropriate depth before it is covered with the new overlay.
Most any project is a candidate for overlay if the existing base is stable and the asphalt pavement is structurally sound. Contact us for answers pertaining any asphalt overlay questions you might have.
Hall Brothers Inc: Asphalt Manufacturer
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Asphalt maintenance – investment or expense?
Asphalt Restoration Technology of Florida, Inc.
“Wherever the road takes you, Asphalt Restoration Technology will be there!”
One of the biggest areas overlooked during budgeting is asphalt maintenance. We look at it every day and yet, when time comes for sealcoating or overlays, we never seem to have budgeted enough, or worse, we don’t even begin to know what to do about the problems anyway.
In an effort to assist property managers and board members, I offer the following terminology in order to familiarize them with asphalt maintenance:
- Asphalt – This is usually the material that your parking lots are made of. It consists of tars, oils, sands, bituminous matter and rock. The original asphalt cap could be as thick as three inches or as thin as one inch.
- Ponding – This is an area where water puddles due to the lack of drainage or the inability to drain properly.
- Unraveling – When the tars, sands, oils and finites begin to dissolve and disappear, your asphalt is left exposed and crumbly.
- Potholes – These are the areas of your asphalt that have deteriorated to the point that the asphalt has been removed or washed away and your subbase is exposed. This, if not taken care of immediately, will continue to grow in size and can do more damage if neglected over a period of time. Potholes occur for reasons such as standing water, high traffic, sealcoat breakdown, gouges and even sinkholes or washouts.
- Cracking – Cracks occur due to numerous reasons from the settling of your asphalt, reaction to sealcoating or just plain old age. Crackfilling is used to seal cracks in your asphalt that are about a fourth of an inch in width. The cracks are routed to a uniform depth and then a hot rubberized material is injected into the crack and leveled. This is usually done prior to an overlay or after your property has been sealcoated or rejuvenated.
- Sealcoating – Sealcoating is a water-based coal/tar emulsion that is applied to your asphalt to protect it as well as give it an aesthetically appealing look. Asphalt sealcoating is sprayed on or squeegeed on, depending on the contractor. Either method is acceptable.
Sealcoating should be applied every one to three years and at times can last longer. Because asphalt sealcoating is water-based, it will eventually fade or peel away as it ages, leaving your property streaky and patchy looking. Signs of sealcoating will be darkened edges and faded travel paths more evident at entrances and turn areas. This is visually unattractive and will only get worse until the next coating is applied.
Another thing to consider is that your asphalt and sealcoating expand and contract at different levels causing the sealcoating to crack and begin pulling apart at the asphalt underneath. As it ages and through weathering, these cracks will begin to grow and join together and will have to be addressed as they will eventually become potholes. They can also cause a complete breakdown of your asphalt cap if not properly maintained. In addition, another downfall of sealcoating is that because it sits on top of your asphalt, it usually takes away the natural resistance of the peaks and valleys caused by the rock and tars. As a result, your property actually becomes more slippery and conditions are better for hydroplaning.
- Rejuvenation – Over time, the tars and oils that surround the rocks that make up your asphalt eventually begin to dry up and evaporate. When this occurs, the rock that makes up the binder becomes exposed causing early stages of deterioration. If left untreated, the rock will eventually become loose and a complete overlay will be needed.
Pavement Dressing Conditioner (PDC) Rejuvenator treatment is an oil-based product that is applied tountreated asphalt in order to reinstate the tars and oils that are lost due to weather and oxidation and will immediately stop the aging process. PDC penetrates and it will expand and contract with your asphalt thus avoiding the cracking that occurs with water-based sealers. Because it is absorbed, it does not alter the surface, making the asphalt more skid resistant when compared to water-based sealcoating. PDC rejuvenator is fuel-resistant and water-resistant as well. It is recommended to apply PDC every three to five years but it has been known to last up to seven years. Most rejuvenators cannot be applied over previously water based sealcoated properties, as the oil-based product cannot penetrate water-based sealcoats. Most rejuvenators are typically applied to asphalt areas that have never been treated of within eight months of curing for new overlays.
- Overlay – There are a couple of different types of overlay. The most inexpensive is applying a one-inch overlay asphalt cap that is put on top of your existing pavement. Most major areas of deterioration will be repaired prior to this type of overlay. This procedure will give your asphalt a brand new look and can be maintained for years to come with properly scheduled maintenance. If you are overlaying on top of previously sealcoated area that has cracks, these crackswill in time rise to the top of your new overlay. Some properties take precautionary measures by having the larger cracks filled prior to the overlay and this procedure is highly recommended.
Another type of overlay is when the contractor will mill out and remove the old asphalt down to the subbase. He will then level and compact this area (subbase) and apply two to three inches of asphalt and roll and compact it to the proper density. This is very beneficial if your property was previously sealed and was experiencing great levels of deterioration in the form of potholes, cracks, and unraveling. This new look will allow you to start over and have the opportunity to start over and to make more educated decisions about maintenance in the coming years.
In order to protect yourself and your decisions, I recommend to all boards and property managers that you make sure the business you are using is registered through the state of Florida. You can check this out by going to www.Sunbiz.org, which is the website for the state of Florida, Division of Corporations. In addition, always remember to get three estimates, ask for references, confirm they have general liability insurance as well as workmen’s compensation and confirm who will be performing the work. There is a limited amount of licensed applicators for the rejuvenation process. Some of the products available do not have the testing or data information regarding their product. If they don’t have it, beware!
Your asphalt doesn’t have to be a funnel for maintenance dollars. With the right maintenance and treatment, your pavement can be an investment rather than an expense.
Article written by Connie Lorenz currently President of Asphalt Restoration Technology of Florida.
Asphalt pavement is utilized in a variety of different applications because of its durability, cost-effectiveness, simplicity of construction, and strength. It is the material of choice for parking lots across the nation because asphalt withstands heavier loads and, when combined with proper asphalt maintenance, lasts for many years.
In order to maximize the life of your asphalt parking lot, it is important to develop a pavement management plan involving routine inspections and ongoing preventative maintenance. The following are common asphalt maintenance procedures for parking lots:
Asphalt Repair & Patching
Patching is a common asphalt repair on areas of pavement with potholes. Potholes occur when water seeps into pavement through unsealed or improperly sealed cracks. When the water freezes, it expands and enlarges the crack. When the ice under the pavement melts, a void is left. Surrounding pavement falls into the void and forms a pothole.
Asphalt Repair Procedure
This process consists of filling the affected areas with hot or cold asphalt mix, depending on the season and/or site location. Detailed specifications on asphalt repair are available for download in our Technical Specs library.
Asphalt Removal & Replacement
As asphalt pavement progresses through its performance lifecycle, its appearance diminishes over time. Fine hairline cracks spread and deepen within the asphalt. Without ongoing maintenance, water may enter through cracks and holes may form, undermining the substrate. In this case, the most effective form of repair is to remove and replace the deteriorated area.
This process consists of several important steps to ensure that the repair is performed properly. Detailed specifications are available for download in our Technical Specs library.
The cost for asphalt removal & replacement depends upon the geographic location, the amount of grading and substrate work required, and other site-specific factors.
In more severe cases of asphalt failure, a long-term and cost-effective solution is to resurface the asphalt pavement (also referred to as overlay). If you notice grade depressions (standing water on the pavement) and/or large sections of alligatored areas (interconnecting cracks forming a series of blocks resembling an alligator’s skin), it is a good idea to have your pavement resurfaced.
Asphalt Resurfacing Procedure
This process consists of several steps including preparing and cleaning the area prior to performing work, leveling asphalt of low areas, grinding of all transitions, adjusting of all drainage structures, and many other steps unique to each site. Detailed specifications on asphalt resurfacing are available for download in our Technical Specs library.
Geotextile Reinforced Resurfacing – An option that may be included with asphalt resurfacing is Petromat. Petromat is a non-woven, petroleum-based geotextile fabric used to retard reflective cracking between the existing pavement and the newly installed asphalt surface. This fabric acts as a waterproofing membrane, while also adding structural support and strength.
Leveling Binder – In low areas, hot asphalt is installed at various depths to adjust pitch to proper grades while increasing parking lot strength.
Butt Joint/Grinding – In areas requiring the resurface to tie into other existing surfaces (i.e., concrete, etc.) asphalt is removed along the perimeter to allow proper depth of asphalt on the edge.
Infrared Asphalt Repair
Infrared asphalt technology is an effective solution for critical repairs. This unique method blends hot-mix asphalt right in with the original and then compacts the area to create a seamless restoration. If you notice potholes–especially in high-traffic areas, pavement heaving or uneven surfaces surrounding catch basins (this is a common problem resulting after several freeze-thaw cycles), or rough surfaces in drive lanes or parking stalls, it is a good idea to consider infrared repair.
Infrared rays allow deep penetration asphalt repair and reclaiming without causing burning, scaling, or separation of the asphalt from the aggregate. Additional benefits include: cost savings, as the project is completed with fewer raw materials; time savings, as this repair option takes less time than traditional asphalt resurfacing; seamless repairs, as the patch bonds to existing surface and produces no joints for water to penetrate; and fewer traffic interruptions, as the patch can be driven on almost immediately. For more information about this unique option, please contact us.
Asphalt Maintenance Facts
As soon as freshly laid hot asphalt pavement mix begins to cool, the aging process begins.
When oxygen in the air and water combine with asphaltic binder of the pavement, a chemical change takes place. At first, this process is necessary for the pavement to become hard and firm. Later, if this process is not arrested, a complete deterioration of the asphaltic binder will take place and reduce the pavement to a layer of loose stone.
Enemies of a parking lot include: gas, oil, sun oxidation, salt, water penetration, and hot or cold weather.
Protect Your Investment
In addition to routine inspections and ongoing maintenance, sealcoating asphalt pavement with a coal tar or asphalt-based emulsion slows pavement deterioration by protecting against the enemies of a parking lot. However, for maximum benefit, sealcoat needs to be applied approximately 12 months after the initial application and then on a regular basis, about every 24 to 48 months, thereafter.
Rose Paving co. – Bridgeview, Illinois