What CRS-2 Means on a Chip Seal Job

CRS means cationic rapid setting. The 2 is a higher viscosity grade used so the binder stays in place under cover stone. It breaks quickly so stone can be seated sooner than with a slow-setting tack. CRS-2 is a distributor-truck material, not a crack filler. The chip size has to match the shot.

Open free asphalt tonnage calculator →

Break the code the way the quote uses it

CRS-2 is a chip-seal binder code, not a brand of driveway coating. CRS means cationic rapid setting. Cationic describes the emulsion chemistry the supplier is using. Rapid setting means the emulsion breaks quickly, so cover stone can be seated and traffic can return sooner than it would with a slow-setting tack such as SS-1h. The 2 is a higher viscosity grade, chosen so the binder stays put under the stone instead of running off a crowned road. You will see it on a distributor truck, sprayed, then covered with chips and rolled. It is not a crack filler from a tube, and it is not hot-mix asphalt. This article explains the code. It does not give a shot rate or a DIY method for spraying binder.

Why the stone and the binder are one system

The chip size has to match the binder shot or the stone will not lock. Too little binder for the stone and the cover leaves, which you hear in the wheel wells. Too heavy a shot and the surface can bleed and shine. The match is a crew and supplier decision based on the stone and the pavement, not a number to copy from a blog. When you read a quote, ask which emulsion, which chip size, and whether they will sweep loose stone after the seal has seated. Ask what happens at driveways and intersections where tires turn. Rapid setting is what lets them move traffic back sooner. It does not mean the fresh seal can be spun on in the first minutes. Follow the crew's return-to-traffic timing rather than inventing one.

How CRS-2 differs from the asphalt tons

A chip seal is a surface treatment. It is not inches of hot mix, and you should not convert CRS-2 gallons into the ton formula. Hot-mix tons, if you overlay later, are area times inches over 12 times 145 pounds per cubic foot divided by 2000, a planning estimate, with the plant ticket as the real weight. The chip-seal quote should speak in emulsion and stone, not in those tons. If a proposal says CRS-2 and also says asphalt tons, ask which line is the seal and which line is hot mix. They are different materials. Sweeping and traffic control matter while the chips are fresh, because loose stone breaks glass. Bald spots later mean the stone did not lock, which is a reason to call the crew back to look, not a reason to paint driveway sealer over the chips.

A practical sequence

Read CRS as cationic rapid setting and 2 as the viscosity grade.
Ask which chip size is paired with the CRS-2 shot.
Treat it as a distributor operation, not as crack filler or driveway sealer.
Keep chip-seal quantities separate from hot-mix tons and the plant ticket.

The mistake to skip

Copying a blog shot rate and treating CRS-2 like a product to spray from a can.

Questions people ask

Is CRS-2 the same as SS-1h?

No. SS-1h is slow setting and is used for tack and light fog, where the emulsion needs time to wet a surface. CRS-2 is rapid setting and higher viscosity so it can hold cover stone on a chip seal and break quickly. The codes are not interchangeable. Ask which one is in the quote and what it is supposed to do. Neither code is a thickness of pavement.

Can I fill cracks with CRS-2?

CRS-2 is a chip-seal emulsion handled from a distributor, not a tube of crack filler. Pouring or spraying it into cracks is not the job it is named for, and this article does not give an application method. Crack sealing is a different product and a different tool. If the quote says CRS-2, expect cover stone and a crew, then a sweep of loose chips.

As an Amazon Associate, AsphaltTons.com earns from qualifying purchases. Product links below are sponsored.