Concrete Calculator for a 2-Car Driveway
A standard residential two-car driveway typically measures 20×20 feet (400 sq ft) to 24×24 feet (576 sq ft). Structural building codes mandate a minimum 4-inch slab for light passenger cars, and 5 to 6 inches with rebar reinforcement for SUVs, pickup trucks, or RV parking.
Instant Concrete Estimator
Real-time cubic yards, 80lb/60lb bags, ready-mix truckloads & 1:2:3 site batch ratios.
Option A: Pre-Mixed Concrete Bags (Rounded Up to Whole Bags)
Yields 0.60 cu ft / bag (rounded up to whole bags)
Yields 0.45 cu ft / bag (rounded up to whole bags)
~920 quarts (~3 qts per 80 lb bag)
A standard half-ton pickup bed maxes out at 1,500 to 2,000 lbs (0.75 to 1.0 ton). This bag order weighs 27,133 lbs and requires 16 pickup trips or a flatbed delivery truck.
* Payload Safety Notice: General physics estimate only. Payload ratings vary by vehicle trim and options. Check your specific driver-door tire and loading placard (GVWR) before hauling aggregate or bagged concrete.
Disclaimer: Calculations provided are estimates for preliminary material planning only. Actual yields vary based on subgrade compaction, site grading, waste, and local trade practices. QuickRenoTools assumes no liability for material shortages, structural failures, code non-compliance, vehicle overloads, or jobsite injuries. Verify all structural spans, retaining wall heights, and concrete mix designs with a licensed engineer, certified contractor, or local building authority prior to purchase and construction. Legal Disclaimer→
Concrete Calculator for a 2-Car Driveway — Quick Reference
Exact material counts across standard depths and load ratings.
| Slab Dimensions & Depth | Concrete Volume (Cu Yds) | Ready-Mix Truck Loads | Delivery Method | Vehicle Load Rating |
|---|---|---|---|---|
| 4" Depth (20×20 ft) | 4.94 cu yds (5.43 w/ 10%) | Ready-mix truck (1 load) | N/A (Bulk Ready-Mix) | Passenger cars only. |
| 5" Depth (20×20 ft) | 6.17 cu yds (6.79 w/ 10%) | Ready-mix truck (1 load) | N/A (Bulk Ready-Mix) | Recommended for SUVs & pickup trucks. |
| 6" Depth (24×24 ft) | 10.67 cu yds (11.7 w/ 10%) | Ready-mix truck (2 loads) | N/A (Bulk Ready-Mix) | Heavy RV, boat trailer, or delivery truck parking. |
Disclaimer: Calculations provided are estimates for preliminary material planning only. Actual yields vary based on subgrade compaction, site grading, waste, and local trade practices. QuickRenoTools assumes no liability for material shortages, structural failures, code non-compliance, vehicle overloads, or jobsite injuries. Verify all structural spans, retaining wall heights, and concrete mix designs with a licensed engineer, certified contractor, or local building authority prior to purchase and construction.
Related Tools for This Project
Building this project? Don't forget your sub-base gravel, reinforcement steel, or finishing supplies:
Step 1: Sub-Base — Calculate 6" of compacted crusher run / road base stone under the driveway.
Step 2: Reinforcement — Calculate #4 (1/2") rebar at 18" spacing to prevent vehicle load cracking.
Step 3: Apron Border — Installing a decorative paver entrance apron or soldier course driveway border.
Project Guide: Concrete Calculator for a 2-Car Driveway
When building a project of this scale, precision in your prep work directly impacts durability. Ensure you excavate below the topsoil layer down to undisturbed subsoil, and always install compacted aggregate base with edge forms braced at minimum 2-foot intervals.
Frequently Asked Questions: Concrete Calculator for a 2-Car Driveway
Common questions about bag calculations, ordering bulk vs bags, and trade standards.
How many cubic yards of concrete for a 20x20 two-car driveway?
A 20x20 driveway at 4 inches thick requires 4.94 cubic yards net (5.5 yards with 10% waste). At 5 inches thick (the recommended contractor standard for SUVs), it requires 6.17 cubic yards net (6.8 yards with waste).
Should a residential driveway be 4 inches or 6 inches thick?
A 4-inch slab is sufficient for light passenger cars. However, contractors strongly advise 5 to 6 inches with #4 rebar for residential driveways where heavy delivery trucks, garbage trucks, SUVs, or RVs may park or turn around.
Can I mix bags of concrete for a 2-car driveway?
No. A 20x20 driveway at 5 inches requires ~270 bags of 80 lb concrete (over 21,000 lbs of material). Mixing this in a barrel mixer risks severe cold joints and premature failure. Always order a ready-mix delivery truck.
What PSI concrete should be used for a driveway?
Specify minimum 4,000 PSI concrete. In northern climates subject to freezing temperatures and de-icing road salts, specify air-entrained 4,000 to 4,500 PSI mix to prevent winter surface spalling.
What sub-base is required under a concrete driveway?
Excavate organic topsoil down to stable subgrade, lay geotextile fabric, and install 4 to 6 inches of compacted dense-graded aggregate (crusher run / road base) compacted with a vibratory roller.
How many control joints does a 20x20 driveway need?
Control joints should divide the slab into square panels no larger than 10×10 feet. Tool or saw-cut one joint down the center in both directions (creating four 10×10 quadrants) at a depth of 1/4 the slab thickness.
How long before I can drive on a new concrete driveway?
You can walk on the concrete after 24 to 48 hours. Wait at least 7 full days before parking standard passenger vehicles. Wait 28 days before parking heavy trucks, motorhomes, or trailers.
What slope should a concrete driveway have?
Maintain a minimum downward slope of 1/8 to 1/4 inch per foot (1% to 2% slope) away from your home or garage to ensure stormwater runs into the street gutter and cannot enter the garage.
How much does a ready-mix concrete truck load cost?
Ready-mix concrete costs approximately $130 to $170 per cubic yard delivered. A 20x20 driveway (6 to 7 yards) typically costs $900 to $1,300 for the raw concrete delivery.
Do I need rebar or wire mesh in my driveway?
Yes. Rebar (#4 / 1/2-inch at 18" grid spacing elevated on 2" plastic chairs) provides vastly superior crack resistance compared to welded wire mesh, ensuring panels remain interlocked even if minor cracking occurs.