Hot-pour rubberized sealant
Kitchener Asphalt Paving Pros fills and seals cracks in asphalt driveways, parking lots and private roads with hot-pour rubberized sealant, melted on site and pressed into clean, dry cracks. It is the least expensive repair we offer and the one that saves the most later, because every open crack is a path for water into the base.
Homeowners usually book driveway crack sealing as a single visit, often just before a sealcoat. Property managers, condo corporations and plaza owners book us each spring or fall to seal the new cracks that every winter opens across their lots.
Over 14 seasons we have sealed cracks on Kitchener clay, sandy Waterloo lots and gravel-based rural lanes. The driveways that reach their full 15 to 25 year life are almost always the ones whose cracks were sealed early.
Causes
Asphalt cracks here because it is a flexible material asked to survive hot summers, deep cold snaps and wet clay. Five causes account for almost every crack we seal.
Soil changes which causes dominate. On the sandy Waterloo Moraine under west Kitchener and Waterloo, cracks are mostly thermal; on the clay till found across much of Kitchener, settlement and frost add to them.
Sun and air dry out the asphalt binder, turning the surface grey and brittle. Brittle asphalt develops fine surface cracks long before it carries any structural damage.
Asphalt shrinks in a cold snap, and when it cannot shrink any further it splits straight across. These transverse cracks open in January and close in July, every year.
Water that gets into a crack freezes, expands and widens it. Our asphalt repair guide covers how that cycle turns a crack into a pothole.
Backfill beside new foundations, old utility trenches and soft clay pockets settle over time, and the asphalt cracks above them. Settlement cracks often follow the line of the trench or garage wall.
Where no curb, lawn or stone shoulder holds the edge, tires push it outward and cracks form a few centimetres in from the side.
Know the difference
Crack filling suits cracks that barely move between seasons; crack sealing suits working cracks that open and close with temperature. Filling places material into a cleaned crack, while sealing first routes the crack into a uniform reservoir so the sealant can stretch without tearing.
Most driveways need both: sealing for the transverse thermal cracks and filling for the rest. We mark each crack on site and price the two separately.
| Feature | Crack filling | Crack sealing |
|---|---|---|
| Crack movement | Little or none between summer and winter | Opens in cold, closes in heat (a working crack) |
| Routing | None; cleaned and dried only | Routed to a reservoir about 19 mm by 19 mm (3/4 in) |
| Material | Hot-pour rubberized sealant; cold-pour emulsion only for hairline cracks | Hot-pour rubberized sealant, ASTM D6690 type |
| Finish | Squeegeed flush or a narrow band | Filled flush or with a thin overband across the edges |
| Expected life | About 2 to 4 years | About 3 to 5 years, often longer |
| Typical use | Longitudinal, block and settlement cracks | Transverse thermal cracks and reflective cracks in overlays |
Identify your cracks
Each crack pattern points to a different cause, so the pattern tells us the treatment. Use these four descriptions to identify what is on your driveway or lot.
Hairline cracks are surface shrinkage and can be filled, then protected by a sealcoat. Thermal cracks run straight across the pavement every few metres and widen each winter, so they are routed and sealed once they reach about 6 mm (1/4 in).
Cracks running lengthwise often follow a paving seam or a weak, unsupported edge. We seal them and, where the edge is moving, add compacted stone along the side so it stops spreading.
An overlay laid over cracked asphalt often shows the old cracks again within a few years. They move like thermal cracks and are sealed the same way; our asphalt resurfacing page explains how prep reduces them.
Cracks joined into small blocks like reptile skin mean the base underneath has failed. Sealant cannot hold broken pieces together, so we quote full-depth asphalt patching instead, or replacement if the area is large.
Materials
We use hot-pour rubberized crack sealant that meets an ASTM D6690 type specification, the standard for hot-applied joint and crack sealants on asphalt and concrete pavement. It is a blend of asphalt, polymers and rubber that stays flexible well below freezing and sticks to the crack walls as they pull apart.
The sealant is melted in an oil-jacketed melter-applicator. Hot oil circulating around the kettle heats the sealant evenly without scorching it, and an agitator keeps the blend consistent from the first crack to the last.
Hardware-store bottles and tubes of cold-pour filler are water-based emulsions that shrink as they dry. They sit in the crack as a thin, stiff skin that pulls away from the walls the first time the crack opens in a cold snap, which is why they rarely last a season.
Our process
Clean, dry crack walls are what make sealant stick, so most of the process is preparation. These are the six steps on every crack sealing job.
We walk the surface, mark which cracks are working and which are stable, and measure the total linear footage for the quote.
A crack router cuts a clean, square reservoir along each working crack. The extra width gives the sealant room to stretch without tearing when the crack opens.
A hot-air lance blasts out dust, sand and loose stone and dries and warms the crack walls. Sealant poured into a damp or dusty crack lets go within months.
Sealant is pumped from the melter through a heated wand and fills each crack from the bottom up, so no air is trapped underneath.
On lots, a thin overband across the edges seals the crack shoulders. On plowed surfaces and driveways we often finish flush, so blades and shovels slide over it.
The sealant firms as it cools, and the surface is ready to drive on within 30 to 60 minutes.
Timing
Spring and fall are the best times for crack sealing, roughly April to early June and September to October. Cracks are about halfway between their widest and narrowest then, and the pavement is usually dry.
Fall booking also suits property managers, since the cracks sealed in October are the ones that would otherwise become April's potholes.
Pricing
Crack filling a typical residential driveway costs $250 to $600 before HST. Commercial hot-pour crack sealing runs $1.00 to $2.50 per linear foot, with routing priced as an extra.
| Job | Typical price | What changes it |
|---|---|---|
| Residential driveway | $250 to $600 | Total crack length, width and how many need routing |
| Commercial hot-pour sealing | $1.00 to $2.50 per linear foot | Crack width, density and traffic control |
| Routing | Extra, quoted per foot | Number of working cracks |
Yearly programs keep each visit small, because only the cracks that opened since last year need sealing. Waiting three or four years means paying for all of them at once, plus the patches where water got in.
FAQ
These are the crack questions we get most often on driveway and lot visits.
Cracks wider than about 25 mm (1 in) are cleaned, packed with backer material or clean sand to within a short depth of the surface, then topped with hot-pour sealant. If the edges are crumbling or the crack has sunk, it is no longer a crack and needs asphalt patching.
Routed hot-pour sealant usually lasts about 3 to 5 years, and filled cracks about 2 to 4. Cold-pour bottle fillers from a hardware store often fail within a single winter.
Yes. Sealcoat is a thin film that does not bridge cracks, so we seal them first and then apply coal-tar-free sealcoating over the whole surface.
Yes, as black lines on grey asphalt, which some owners like and some do not. A sealcoat over the whole driveway afterward makes the surface one even colour.
You can fill hairline cracks with a cold-pour product, but it will need redoing most years. Working cracks need routing, a hot-air lance and hot-pour sealant to last, which is equipment most homeowners do not own.
Fall booking
September and October are the last reliable weeks to seal cracks before the freeze, and the slots fill quickly. Book a visit and we will measure your cracks and price filling and sealing separately in writing.