Crack Filler or Crack Sealer for a Commercial Asphalt Lot? How to Tell

Asphalt crack filler and crack sealer are different products for different cracks. Crack filler is a cold-applied material for narrow, stable cracks that barely move. Crack sealer is a hot-poured rubberized sealant, normally placed in a routed channel, for cracks that open and close with the seasons. A crack that has come through a few Ontario winters has usually moved, so it usually needs sealer, not filler.

Asphalt crack filler vs crack sealer at a glance

The two words get used loosely, and some quotes use them for the same line item. The products and the prep are different, so the first job is to find out which one a quote actually means. The table below follows the terms used in a Canadian national guide to crack treatment, which separates crack filling from crack sealing.

What asphalt crack filler is and when it works

Asphalt crack filler is the pourable black material most people picture: a cold-applied emulsion that goes into a hairline crack and dries. The pails sold as driveway crack filler work the same way. It is quick to apply and cheap, and the crack is not routed. It is blown clean with compressed air and the material is flushed in.

Filler works when three things are true. The crack is narrow, with the national guide putting the line at about 3 mm. The crack is young, meaning it formed in the last year or so. And it barely moves. A stable hairline in a lightly used corner of a lot fits. A crack across a drive aisle where plows and delivery trucks run does not.

Weather matters more with filler than people expect. The guide recommends cold-pour emulsion in late spring, in air above 15°C, though it can go down to 10°C. At 15°C the surface skins over in 15 to 45 minutes, but a full cure takes 8 to 12 hours, and rain or a freeze inside 24 hours can wreck it. So does asphalt crack filler work? Yes, on the right crack, for a short time. It stops working when the crack opens and closes under it.

What asphalt crack sealer is and why moving cracks need it

Asphalt shrinks in the cold. An active crack, typically wider than 3 mm in summer, opens 15 to 100 percent wider in winter, according to the same guide, and closes up again when the weather warms. That cycle repeats every year. Anything placed in the crack has to stretch and recover without pulling away from the walls.

Crack sealing is built for that. The crack is routed so the channel is at least as wide as it is deep, which gives the sealant a shape that stretches instead of tearing. The channel is cleaned and dried with compressed air or a hot-air lance, because sealant will not bond to dust or damp. A hot-applied rubberized sealant, heated until it pours, is then placed and finished. Clean, dry and hot is the whole recipe.

Hot-applied sealants are commonly specified to ASTM D6690, which has four types tested at different cold temperatures. Ask which type is quoted and whether it suits cold climates. Do not confuse crack sealer with sealcoat. Sealcoat is a thin protective coating over the whole surface. It slows oxidation and salt damage, but it does not fix structural failure and it does not replace a sealed crack.

How long crack filler and crack sealer last in Ontario

Nobody can promise a number, and a product label is not a promise either. What can be said comes from field studies in Canadian cities. The 2003 national guide reported that cold-pour emulsions used for crack filling typically fail after one or two winters. The guide put typical hot-pour sealant durability at two to seven years, well short of the six to twelve years its authors said a good sealant should deliver.

Plaza lots see slower traffic than city arterials, but plowing, salt and a winter that swings across freezing add their own wear. Treat the figures as a planning range. The useful test is February, not summer. Cracks are at their widest then, and sealant that is going to fail shows it. In summer, sealants can heal and look effective even when they are not.

Life depends on four things: how clean and dry the crack was, how well the product was chosen for cold, how much the crack moves, and how much traffic and plowing runs over it. A good plan has you walk the lot each spring, note which sealed cracks have opened, and touch them up. The same guide says crack treatment can extend pavement life by two to five years, but only on pavement in reasonable condition.

Which cracks get filler, sealer or neither

Use the crack, not the product name, to decide. Measure a few cracks in spring and look at how the pavement around them is doing.

The guide is blunt about the last two rows: treating pavement in poor overall condition is not effective. A lot with dense cracking across much of its area needs patching or resurfacing, and the asphalt patching methods guide explains how those repairs are chosen.

Timing in Ontario is a compromise. Cracks are mid-cycle in spring and fall, which is easiest on the sealant. Late summer to mid fall is a good window for sealing active cracks. Late spring can work if the pavement has dried out. Avoid damp cracks and early-morning dew in September and October, because moisture ruins the bond. Cold-pour filler belongs in late spring, as noted above. For a seasonal view, see the parking lot crack sealing guide and the pothole prevention guide.

How to read a crack sealing line item and avoid the wrong product

A single line reading crack sealing with a metre count tells you almost nothing. Ask for the following in writing so that two bids can be compared.

• Method: routed or not routed, and hot-pour or cold-pour. Rout and seal is crack sealing. Cleaning and flush-filling is crack filling.
• Material: what product and what specification, and whether it is made for cold climates.
• Prep: how cracks are cleaned and dried, and what happens if a crack is damp on the day.
• Which cracks: a width range, and what happens to cracks outside it. Wide, crumbling cracks should appear as a patching line item, not be quietly filled.
• Quantity and unit: linear metres, and whether the count is measured or estimated.
• Timing and closure: temperature and dry-weather conditions, cure time before traffic, and which stalls are blocked when.

Price follows the same list. Total crack length, crack width, routing, cleaning effort, the product used, traffic control around a busy plaza and the cost of getting a crew on site all move it. Bundling with patching or sealcoating can spread the set-up across more work, and the sealcoating guide covers that order of work. Cracks go first, sealcoat after.

D&D Commercial Services offers crack sealing with hot-poured rubberized sealant as part of its parking lot maintenance work. A free written estimate lists the scope, materials and timing, so you can see exactly what each crack gets.

Crack filler and crack sealer questions property managers ask

Does asphalt crack filler work?

It works on narrow, young, stable cracks, under about 3 mm, that barely move. On a crack that opens and closes with the seasons it tends to split or pull away. Cold-pour emulsion often lasts only one or two winters, so check treated cracks each spring and expect to touch them up.

How long does asphalt crack sealer last?

A national guide to crack treatment reported two to seven years for hot-pour sealants in Canadian cities. Results depend on prep, product, crack movement and traffic. Judge performance in February, when cracks are widest, and ask your contractor what they expect for your lot instead of relying on a single figure.

Can I use hardware-store crack filler on a commercial lot?

You can, but it is rarely the right product. Pail fillers are cold-applied emulsions meant for small, stable cracks. A commercial lot has plows, delivery trucks and salt, and most cracks that matter move. Hot-poured crack sealer in a routed, cleaned crack is usually the better match.

What does asphalt crack sealing cost?

Price depends on total crack length, crack width, whether routing is needed, how much cleaning each crack takes, the product used, traffic control and access. It is quoted by the linear metre. Ask for a written estimate that states the method and material, so the line items can be compared fairly.

Should cracks be sealed before sealcoating?

Yes. Seal cracks first, let the sealant set, then sealcoat. Sealcoat is a surface coating that slows oxidation and salt damage. It does not fix structural failure and will not hold a crack closed. Patching of failed areas comes before both.

Devon Moore, Operations Lead Founder & Operations Lead — D&D Commercial Services

Devon Moore is the founder and Operations Lead at D&D Commercial Services, delivering professional commercial property maintenance across Waterloo Region.