Whether it’s parking lots or parking garages, walkways or sidewalks – to get the most out of any pavement investment, remaining on time with maintenance is key.
If properly installed, concrete and asphalt should show minimal signs of damage for the first 3-5 years. Following this period, the pavement’s service life will be determined by how well it is maintained.
Regular maintenance can extend pavement life and improve surface performance, and preserving the pavement’s condition is far more cost effective than repairs or replacement.
As Pavement Ages, it Passes Through a Series of Phases
Properly installed asphalt and concrete will age slowly, and property owners can expect 30+ years from well-installed pavement – but it does eventually transition from excellent to poor condition. This process is gradual, to the point that the owner may not notice it occurring. This is especially true just after installation, as asphalt and concrete should show few signs of wear or damage within the first five years of their service life.
Around the five-year mark, pavement may start taking on enough wear that it’s no longer considered to be in excellent condition. Cracks, discoloration, a pothole here or there – it’s at this point where minor repairs can put off major issues.
If Performed Early in its Life Cycle, Pavement Maintenance Can Delay Expensive Repairs
This pavement life cycle (and how on-time maintenance can extend it) has been visualized many times. One diagram, produced by the University of Minnesota for Transportation Studies, shows the following:
- Pavement spends the first 70+ percent of its life in excellent to fair condition.
- Pavement deteriorates quickly past this point, moving from fair to very poor condition over the last 30 percent of its lifespan.
- For every dollar invested in keeping pavement in fair to good condition, it will save $4-5 in repairs made to the pavement when it is in fair to very poor condition.
There’s a strong financial incentive to invest in pavement preservation and regular maintenance. Doing so will not only extend the life of any pavement projects, it will also protect the company from sudden, budget-busting repairs or replacement.
The Asphalt Life Cycle: How it Ages and How Maintenance Extends its Performance
Asphalt should last decades before full-depth replacement is needed. To extend its life that far, though, the pavement must be kept on its recommended maintenance and preservation schedule. That includes:
- Sealcoating – New asphalt should be sealcoated right after installation and every 2-3 years thereafter, depending on how much traffic the pavement receives.
During sealcoating, an asphalt emulsion is applied to the asphalt’s surface, either with push brooms, hand-held sprayers, or a skid-mounted sprayer. The sealcoat is a low-viscosity fluid that seeps into the asphalt’s surface layers and forms a protective layer over them. This top layer protects the asphalt from UV rays, rain, dust, and some chemical spills.
It has a second benefit of bonding the surface-level aggregate together, making it slightly more resistant to cracking and potholes.
- Crack filling – Asphalt cracks facilitate water intrusion into the pavement, so the sooner they’re filled, the better. Pavement contractors typically do this by melting rubberized asphalt and depositing it within any cracks. Once this compound cures, it provides excellent protection against moisture and dust and also flexes with the pavement, so the crack is slower to widen or spread.
- Pothole patching – Potholes must be addressed as soon as they appear, as their presence indicates base problems. If the rest of the pavement is still in fair or better condition, patching the potholes with new asphalt is a cost-effective way to spot treat it.
During patching, the failed areas of pavement are cut and extracted out. The underlying base is reconditioned and stabilized, the exposed surfaces are tacked and a new asphalt hotmix is rolled into the patch. This patch will be ready for vehicle traffic within 24 hours.
- Overlaying, chip seal and other surface treatments – When asphalt reaches middle age or so, more extensive forms of resurfacing may be needed. While more expensive than crack or pothole repairs, overlays, chip seals and other surface treatments can extend the pavement’s life by several years.
During an overlay, the existing asphalt surface is milled to a depth of 1-2 inches, depending on how thick the new overlay will be. Any base issues are identified and corrected, then new asphalt is rolled over the existing pavement.
During chip sealing, asphalt binder is sprayed on the pavement surface and aggregate pressed into it. Chip sealing is recommended for lower traffic roads.
There are other surface treatment options, such as fog sealing, slurry sealing and crack sealing. The best choice depends on several factors that an asphalt contractor will be best qualified to assess.
With these asphalt preservation tasks on the schedule, the pavement’s flexibility and structural integrity can be protected and therefore extend its service life.
The Concrete Life Cycle: How Maintenance Benefits the Pavement’s Long-Term Condition
One of concrete’s advantages over asphalt is its low-maintenance engineering. Concrete has few maintenance needs, but when it does require attention, it’s usually because there’s a problem that necessitates repair. There are a couple of concrete maintenance routines that can improve the pavement’s lifecycle, including:
- Surface and joint sealing – Sealing the concrete’s surface will greatly slow moisture and dust intrusion, and it’s essential for any concrete that will be regularly exposed to water. Sealants include silicones, silanes, and others, and they generally do the same thing – penetrate into the concrete and cure. Sealants essentially take up the spaces that water would find, keeping that water from causing damage.
Concrete joints impart flexibility into the pavement, but they can become major access points for water if they aren’t sealed every 5-10 years. Polymer sealants are a common option and may include polysulfide or polyurethane-based products.
- Crack repairs – Concrete cracks, like asphalt cracks, are emerging weak spots in the pavement that must be addressed if they’re showing signs of widening or spreading. Concrete cracks are addressed using patching compounds, epoxies, latex, or other sealants.
Commercial crack repair may involve routing the crack before sealing it to create a uniform surface for the sealant. It may also involve stitching the crack or drilling out plugs for deeper grout or epoxy injections.
These repair methods aren’t considered a structural fix, but they will slow the onset of more severe forms of damage.
The above maintenance routines will minimize water intrusion into the pavement, protect the pavement from thermal stresses, and isolate minor areas of damage before they compromise the entire slab.
Performing Pavement Maintenance Now Means Reducing Future Repair Costs
Many property owners think of pavement maintenance in terms of cost, but it’s really a type of investment. By investing in lower cost forms of pavement preservation, property owners extract more overall value from their parking lot, access road, walkway, or any other paved area. Regular concrete or asphalt maintenance can save thousands of dollars down the road and provide many more years to the pavement’s life.
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