Tack Coat Calculator
Convert a specified residual asphalt rate into distributor quantity and optional tank loads.
Tack Coat Calculator
Tack coat results
The distributor quantity is adjusted for both emulsion residue and added water.
Residual rate and distributor rate are different
The project specification may state a residual asphalt rate. The distributor applies a larger liquid volume because an asphalt emulsion also contains water, and the mixture may be diluted again before spraying.
This calculator first finds the residual binder required for the measured area. It then divides that amount by the supplier residue percentage and the share of undiluted emulsion in the final mixture.
The FHWA Tack Coat Best Practices technical brief recommends writing application requirements in terms of residual asphalt so the intended quantity is not confused with diluted or undiluted spray rate.
Confirm the specified rate, permitted dilution, calibration method, and surface condition with the project documents and emulsion supplier before spraying.
Keep tack coat separate from surface seal quantities
Tack coat bonds pavement layers. For driveway surface coating, use the sealcoat calculator. For hot-mix tonnage above the tack coat, use the asphalt calculator.
FAQ
Should I enter the residual rate or the distributor spray rate?
Enter the target residual asphalt rate from the project specification. The calculator converts it to the distributor rate after accounting for emulsion residue and added water.
What does undiluted emulsion share mean?
It is the portion of the final distributor mixture that is original emulsion. For a 70:30 mixture of emulsion and added water, enter 70%.
Where do I find the binder residue percentage?
Use the residue or evaporation residue listed on the emulsion supplier's data sheet. Do not assume that every tack coat product has the same percentage.
Does this calculator select a tack coat application rate?
No. Surface condition, pavement type, milling, absorption, and the project specification determine the target rate. This tool converts a specified residual rate into a quantity to apply.