NovaChip Ultra-Thin Overlay: Step-by-Step Construction Process

What Makes NovaChip Different

NovaChip is a polymer-modified ultra-thin hot-mix overlay, typically 20-30 mm thick, placed on a sound existing pavement that has already been crack-sealed and surface-prepared. It restores skid resistance and profile while adding structural depth only modestly. The process is unforgiving: temperature, tack coat rate and compaction timing must all be controlled tightly.

The 8-Step Construction Sequence

1. Pre-construction survey: Crack-seal all working cracks, patch potholes, mill isolated high spots; deck must be clean and dry.
2. Tack coat: Spray modified emulsified asphalt at 0.3-0.5 L/m² (residual). Allow it to break and turn brown before paving.
3. Mix production: Polymer-modified asphalt binder PG 76-22, gap-graded aggregate, 20-30 mm nominal max; plant temperature 165-175°C.
4. Hauling: Cover trucks to keep heat loss under 10°C per hour; paver start temp ≥ 155°C.
5. Paving: Use a high-density screed paver; lay 20-25 mm at constant speed (2-4 m/min); no hand-leveling on the surface.
6. Compaction: Break with steel-wheel rollers immediately behind paver while mat > 140°C; finish below 80°C. 2-3 breakdown passes, 1-2 finish.
7. Cooling and opening: Open to traffic only when mat temperature drops below 50°C; usually 30-60 minutes in warm weather.
8. Quality check: Core thickness, density (Gmm), smoothness (IRI) and friction test (BPN) before acceptance.

Key Temperature and Thickness Targets

Common Mistakes to Avoid

• Paving on wet tack coat or unbroken emulsion - causes slippage failures.
• Rolling too late once the mat cools below 100°C - you cannot compact cold asphalt.
• Too thick (> 30 mm) - defeats the purpose and causes shrinkage cracking.
• Placing NovaChip on a structurally failed road - it is a wearing course, not a structural repair.