Concrete vs asphalt parking lot cost: the same lot, the same scope

The asphalt side uses the resurfacing calculator's full-depth method, which removes the old pavement, builds a new base and lays new asphalt, with no castings or restriping. The concrete side uses the concrete parking lot calculator's defaults (a 5 in slab with welded wire mesh, 4 in of aggregate subbase and sawcut joints) with removal of old asphalt turned on, so both prices start from the same old lot and end with a new one.

On every size, concrete costs roughly two thirds more up front. The gap per square foot barely changes with size, because the only fixed costs are mobilization, $2,500 for concrete and $1,500 for asphalt. A 2 in asphalt layer instead of 3 in lowers the asphalt side further: $42,488 on 10,000 sq ft, $83,475 on 20,000 and $206,438 on 50,000.

Split the 20,000 sq ft prices into ground work and pavement and the two are close on the first half. Concrete pays $30,000 to remove the old asphalt, $7,000 for fine grading and $14,400 for 450.0 tons of subbase, $51,400 in all. Asphalt pays a single $55,000 line for full-depth removal and a new base.

The difference is the pavement. The concrete lot needs 324.1 cu yd of ready-mix at $51,852 and $45,000 to place, finish and cure it, plus $7,000 of mesh, $3,520 for 3,200 LF of sawcut joints and $2,500 of mobilization, $109,872 in all. The asphalt lot needs 362.5 tons of hot mix at $38,063, $1,600 of tack coat and $1,500 of mobilization, $41,163 in all.

Two concrete options narrow the gap. Leaving out the mesh takes the concrete price to $154,272; NRMCA's CIP 6 sheet notes that wire mesh will not prevent cracking, and the joints are what control it. Keeping the mesh but leaving out the subbase gives $146,872. The ASCC brochure says an aggregate base is sometimes used under concrete to improve the contractor's working platform or to reduce pumping and erosion, and that it does not increase the structural number. Whether either is right for your soil is a question for the designer.

If the site is bare ground, the concrete calculator gives $131,272 for the default 20,000 sq ft lot, $6.56 per sq ft. The asphalt calculator has no bare-ground option: its full-depth line always includes removing old pavement. So do not set a bare-ground concrete price against the full-depth asphalt price, or the asphalt side carries demolition the concrete side does not.

The American Society of Concrete Contractors' parking lot brochure, which draws on ACI 330R-08, shows equivalent concrete and asphalt sections by duty. For light-duty commercial, retail and office parking it shows 4 or 5 in of concrete against 3 in of asphalt on 6 in of aggregate base or 3.5 in on 8 in. For medium-duty mixed use it shows 6 in of concrete against 4 in of asphalt on 10 in of base, and for heavy-duty truck facilities 7 in of concrete against 5 in of asphalt on 10 in of base. The brochure says the illustrations are for quick reference only and that real thickness depends on the soil and the intended use.

The table prices the concrete side on 20,000 sq ft with old asphalt removed. The asphalt calculator stops at 3 in, and its new base is one rate per square foot that does not change with base depth, so it covers only the light-duty asphalt section. For medium and heavy duty, get an asphalt quote for the thicker section and compare it with the concrete line.

Asphalt is maintained with crack sealing and sealcoat. FHWA's asphalt pavement preservation guide says agencies expect their asphalt pavements to last at least 20 years, that treatments such as crack sealing work well when done before the structure is damaged, and that crack and fog seals suit pavement in excellent to good condition and can extend its life by 1 to 4 years. In the EstiCube sealcoating calculator, two coats of asphalt emulsion with crack prep, mobilization and traffic control cost $3,600 on 10,000 sq ft, $6,700 on 20,000 and $16,000 on 50,000. Sealing cracks on their own is priced per linear foot in the crack sealing calculator, where 800 LF of medium cracks in hot rubberized asphalt comes to $1,955.

Concrete is maintained at the joints. FHWA's tech brief on joint sealing says the broad view is that sealing extends the service life of concrete pavements, but that whether a pavement needs sealed joints is likely project specific. It gives typical sealant lives, citing ACPA: 3 to 8 years for hot-poured sealants, 8 to 10 years for silicone and up to 20 years for preformed seals. EstiCube has no joint resealing calculator, so get that price from a contractor, and ask whether the joints in your design are sealed, filled or left open.

This guide does not quote a service life for a concrete parking lot. The ASCC brochure claims concrete has a much longer life than asphalt, which is an industry claim, and we did not find a parking lot figure from FHWA or ACPA to set against FHWA's 20 years for asphalt. Compare the bids over the years each contractor will stand behind, and ask for the maintenance each pavement needs in that time.

Asphalt wins on first cost at every size and thickness these calculators price, so it is the usual choice for a car lot where the budget is set by the up-front number. Plan for its upkeep, sealcoat and crack sealing, in the operating budget.

Concrete makes its case in a few situations: