With our harsh climate here in Quebec, asphalt is subjected to enormous stresses. Under the influence of freeze/thaw cycles and water infiltration, it tends to crack, swell and buckle. Is this kind of damage irreparable? Not necessarily. If the defects are well delineated and affect only a limited area, you can correct them yourself, or hire a contractor to do the work. Here are some tips to help you choose the right repair option.
First aid for asphalt
When cracks or other damage appear in your driveway or other asphalt structure, the earlier you take action to fix the problem, the longer the repair job will last. Every new crack provides another path for water to infiltrate the pavement—and water is the chief enemy of asphalt. To prevent more extensive deterioration, there are simple actions you can take, depending on the nature of the problem.
Small crack (less than ¾ in.)
- Fill the crack with rubberized asphalt emulsion-based crack sealer and allow to dry.
- The mix will need to be more or less liquid depending on the dimensions of the crack.
Major crack (More than ¾ in.) or pothole
- Fill the crack using cold-mix asphalt specially designed for this type of repair work.
- Prepare the surface according to the manufacturer’s instructions, and then pour the product into the cavity.
- Compact manually.
- For better results, finish levelling the asphalt by placing a board on top of the repaired surface and rolling over it with your car.
More extensive damage? Call in the specialists
If the damage is over a wide area or the defects are significant, it’s best to hire a specialized contractor, who will use suitable equipment and products, including hot-mix asphalt. Essentially, the contractor will take the following actions:
- Mark off the surface to be repaired. This zone should extend slightly beyond the actual area of damage.
- Cut along the markings with a special saw, which will make it easier to remove the damaged asphalt, prevent the undamaged pavement from being altered by the repair job, and allow for a neater patch.
- If needed, spread granular material (e.g., gravel) and compact it.
- Heat the edges of the existing asphalt so that it will properly fuse with the hot repair mix.
- Lay the hot-mix asphalt to a compacted thickness of at least 2 in.
If the job involves repairing slight dips—e.g., ruts resulting from the weight of a parked vehicle—removing the asphalt may not be the solution. The best course of action may be to apply a layer of tack (glue) and then lay asphalt on top to fill the depression.
Resurfacing: giving new life to asphalt
Even if best practices are followed, any asphalt coating will deteriorate eventually. After 20 years, the surface will often become so rough that it’s nearly impossible to sweep. Can simple resurfacing suffice to repair it? Yes, on some conditions:
- The granular base must be of good quality. Look for cracks, potholes or swelling in the asphalt: if there are none, or only few instances, this is a good indication that it is.
- The drainage slope must have been maintained over the years.
- The ground level and the adjacent building must allow room for the extra layer of asphalt.
Only a qualified, experienced contractor, taking into account the condition of the existing asphalt coating, can tell you whether resurfacing is a worthwhile, durable option. If so, the contractor will perform the following steps:
- Clean the surface to be covered.
- Apply a tack coat to enable the new coating to bind properly to the existing pavement.
- Spread a new layer of quality hot-mix asphalt to a compacted thickness of at least 2 in.
Is this type of repair good for the long haul? Certainly. You’ll have a thicker layer of asphalt laid over a base that has benefited from several years of compaction—in other words, optimum conditions!