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Tips - Optimum Standards and Specifications

Optimum Standards and Specifications

Based upon various cities, counties and MDOT specs,and on average loads and soils

 Sub-base    6 inches     21-AA limestone  
 Base    2.5"    20-A asphalt  
 -    2.5"    20-AA asphalt  
 -    2.5"    20-A recycled asphalt  
 Top    1.5"    36-A asphalt  

For maximum life (approximately 15-20 years) and reduced repairs. "Reduced thickness usually means reduced life."