ADA / Illinois Accessibility Code
Federal Americans with Disabilities Act and Illinois Accessibility Code regulate accessible parking — stall counts, dimensions, slopes, signage, and detectable warning surfaces. Compliance is required at all commercial properties open to the public.
Aggregate Base
The crushed stone layer beneath the asphalt. Distributes load to the sub-grade. Standard for commercial: 6 to 12 inches of CA-6 aggregate, compacted to 95% standard Proctor density.
Alligator Cracking
Interconnected cracks resembling alligator skin. Signals sub-base failure. Can’t be patched — requires full-depth reconstruction of the affected area.
Asphalt Emulsion
Asphalt suspended in water with emulsifier additives. Used for tack coats, sealcoating (when blended with mineral fillers and additives), and crack sealing in some products.
Binder Course
The lower layer of asphalt in a two-lift pavement system. Coarser and denser than the surface course. Provides structural strength.
CA-6
Illinois aggregate gradation — graded crushed stone used as parking lot base aggregate. Specified by the Illinois Department of Transportation.
Catch Basin
Inlet structure connecting the parking lot to the storm sewer. Has a frame and grate at surface, walls of precast or cast-in-place concrete, and pipe connection to the storm system.
Coal Tar Emulsion
Sealcoating product based on refined coal tar. Excellent chemical resistance to oil and gas. Restricted in some Chicagoland municipalities for environmental reasons.
Compaction
The process of densifying asphalt or aggregate with rollers. Standard target: 92 to 96% of theoretical maximum density for asphalt, 95% standard Proctor density for aggregate.
Crack Sealing
Hot-pour rubberized polymer applied to asphalt cracks to prevent water infiltration. The highest-ROI pavement maintenance treatment.
Detectable Warning Surface (Truncated Domes)
Federally-required surface treatment with raised dome pattern at locations where pedestrian routes cross vehicular traffic. ADA requirement for compliance.
Fire Lane
Designated emergency-vehicle access route in a parking lot. Marked with red paint, signage, and lettering (‘FIRE LANE — NO PARKING’). Width and lettering specified by local fire marshal.
Full-Depth Reconstruction
Complete removal and replacement of asphalt and aggregate base. The most expensive repair but produces a 20- to 30-year service life.
Geotextile Fabric
Synthetic fabric placed between sub-grade and aggregate base to separate fine soils from aggregate, distribute load, and reinforce weak sub-grade. Common in industrial and high-load applications.
IDOT Pre-Qualification
Illinois Department of Transportation certification that a contractor meets technical, financial, and execution standards for state DOT projects. A credibility marker for commercial contractors.
Mill-and-Overlay
Partial-depth resurfacing — milling 1.5 to 2 inches of failed surface and paving a fresh layer on top. Half the cost of full reconstruction. Service life: 12 to 18 years.
MUTCD
Manual on Uniform Traffic Control Devices. Federal standard for traffic signs, signals, and pavement markings. Referenced in commercial parking lot striping requirements.
Polymer-Modified Binder
Asphalt binder enhanced with polymer additives for improved high-temperature performance, low-temperature flexibility, and durability. Used in heavy-traffic commercial mixes.
Saw-Cut Patching
Pothole repair method using a saw to cut a clean rectangular perimeter, then excavating, filling with hot-mix asphalt, and compacting. Permanent repair when done correctly.
Sealcoating
Thin protective coating applied to asphalt surface. Extends pavement life by protecting against UV, oil, water, and freeze-thaw damage. Recommended every 2 to 3 years for commercial properties.
Sub-Grade
The native soil beneath the aggregate base. Foundation of the pavement system. Sub-grade failure is the #1 cause of pavement collapse.
Surface Course
The top layer of asphalt in a two-lift pavement system. Smoother and denser than the binder course. The driving surface.
Tack Coat
Asphalt emulsion applied between layers of asphalt to ensure bonding. Critical for mill-and-overlay and for long-term lift integrity.
Thermoplastic Striping
Pavement marking material applied hot from a kettle. Lasts 3 to 5x longer than paint. Required for many municipal and DOT pavement marking applications.
Wheel Stops
Precast concrete blocks placed at the front of parking stalls to prevent vehicles from over-running the stall line. Common at properties with heavy turnover.
Get a Free Commercial Paving Estimate
Need help with a commercial paving project? Every estimate is free, on-site, and itemized. Most on-site estimate within 48 hours, with on-site estimate within 48 hours. Use the form on this page or call (630) 555-PAVE.
Get a Free Commercial Paving Estimate
Need help with a commercial paving project? Every estimate is free, on-site, and itemized. Use the form on this page or call (630) 555-PAVE.