TryBuildCalcDouble-Car Driveway Calculator (20-24 ft Wide)
Size your double-car driveway instantly.
🕒 Last updated: September 7, 2026
Inputs
ℹ️L-Shaped models a main run plus a second connected section — an apron, turn, or widened area — as two rectangles added together.
ℹ️Distance from the street/curb to the garage or parking area.
ℹ️Single-car driveways are typically 10-12 ft wide; double-car driveways are typically 20-24 ft.
ℹ️4 in covers standard passenger vehicles and SUVs; go to 5-6 in for pickup trucks or an RV; 8 in for frequent heavy commercial traffic.
Base / Sub-base
ℹ️6 in compacted base is standard for residential driveways; go deeper in soft, clay-rich, or high-water-table soil.
Reinforcement
ℹ️Wire mesh and rebar both control crack width after cracking occurs — neither prevents cracking itself; control joints do that.
ℹ️Standard 5 x 10 ft sheets, overlapped at least one mesh square (commonly 6 in) at every edge.
Concrete Source & Waste
ℹ️Ready-mix truck is standard for a full driveway pour; bagged premix is more common for a small apron or DIY patch.
ℹ️Standard mixer trucks carry around 9-10 cu yd per load.
ℹ️Applied to the concrete order volume — 8% is a common estimating default for a slab pour.
Cost
Concrete Needed
5.33 cu yd
144 cu ft (4" thick, +8% waste)
Truck Loads
1
1 partial delivery: 5.33 cu yd (truck capacity 10 cu yd)
Driveway & Concrete
Area: 400 sq ft (20 × 20 ft)
Volume before waste: 4.94 cu yd
Control joints (10 ft spacing, both directions): 2
1 transverse + 1 longitudinal
Base / Sub-base
Quarry Process (QP) — US driveway base, 6" deep
Volume: 7.41 cu yd
Weight (+8% waste): 14.34 tons
Reinforcement
Welded wire mesh, 10 × 5 ft sheets, 6" overlap
Layout: 3 × 5
Sheets needed: 15
Assumptions Used
Standard US residential concrete driveway, rectangular or L-shaped (a main run plus a second connected section). Concrete volume is length × width × thickness per section, summed for L-shaped, with waste applied to the order volume. Base material weight uses the selected material's published density with a 15% compaction allowance and 8% waste, matching the site's general base-material calculator. Control joint spacing follows the widely-used "2 to 3× slab thickness, in feet" rule of thumb (clamped to a practical 8-15 ft range), applied in BOTH directions so panels stay roughly square rather than long, narrow strips — matching NRMCA/ACPA guidance. Wire mesh sheet count accounts for overlap only between adjacent sheets (never the first sheet) and checks both sheet orientations for the fewer-sheet layout. Rebar quantities include lap-splice material (40× bar diameter) for any run longer than one 20 ft stock length. Reinforcement — welded wire mesh or a rebar grid — controls crack WIDTH after cracking, it does not prevent cracking; control joints do that. This calculator computes material quantities only — it does not verify subgrade compaction adequacy, local frost depth requirements, or structural design for unusual soil or loading conditions.
Bill of Materials
Main material: 1 truck load + recommended tools
+−
Bill of Materials
Main material: 1 truck load + recommended tools
Computed items reflect your entered length, width, and thickness; consumables below are general recommendations — actual needs vary by product and site conditions.
For Your Job
Concrete
Base Material
Wire Mesh
General Tools & Consumables
Curing compound or curing blankets
Isolation/expansion joint filler
Rebar chairs or mesh supports
Concrete saw (joint cutting)
Bull float / hand float
Broom (finish texture)
Plate compactor
Screed board / screed rail
Forms (wood or metal)
Safety glasses & work gloves
Diagram simplified for clarity (not to scale) — joint and reinforcement layout shown schematically.
Looking for the verification checklist, reference tables, tips, or common mistakes?See the complete Concrete Driveway Calculator.
Double-car driveway material takeoff
A double-car driveway is typically 20-24 ft wide, sized to fit two vehicles side by side.
This page defaults to a 20 ft × 20 ft slab at 4 in thick — edit the inputs above to match your actual driveway.
Concrete Driveway Calculator Formula: How Is It Determined?
Concrete volume, base material, reinforcement, and control joint layout, calculated separately and combined into a material takeoff.
Step 1 — Concrete Volume
Area = Length x Width
Volume = Area x Thickness
Order Volume = Volume x (1 + Waste Factor)
Straightforward slab volume — length times width times thickness, with a waste allowance applied to the order volume. Ready-mix orders fill as many full trucks as the volume allows, plus one partial delivery for the remainder — only the DELIVERY COUNT rounds up, not the volume itself. Bagged orders round up to full bags using each bag's published cubic-foot yield.
Step 2 — Base Material
Base Volume = Area x Base Depth
Base Weight = Base Volume x Material Density x (1 + Compaction%) x (1 + Waste%)
Reuses the same base-material density and compaction/waste logic as the site's general base-material calculator — a 15% compaction allowance and 8% waste are applied by default.
Step 3 — Control Joints
Joint Spacing = clamp(2.5 x Thickness (in), 8 ft, 15 ft)
Transverse Joints = ceil(Length / Spacing) - 1
Longitudinal Joints = ceil(Width / Spacing) - 1
Follows the widely-cited "2 to 3x slab thickness, in feet" rule of thumb, clamped to a practical residential range — and applies the SAME spacing to BOTH the length and width, per NRMCA and American Cement Association guidance, so panels stay roughly square instead of long, narrow strips on a wide driveway.
Step 4 — Reinforcement
Mesh: Sheets = tile Length x Width with 5x10 ft sheets (overlap only between sheets, both orientations checked)
Rebar: Bars = ceil(Width / Spacing) + 1 (each direction) + ceil(Length / Spacing) + 1
Rebar order length = coverage length + (splices x 40 x bar diameter), for any run over 20 ft
Wire mesh tiles standard 5 x 10 ft sheets across the driveway footprint — overlap only reduces the space BETWEEN sheets, never the first sheet, and both sheet orientations are checked to find the layout that uses fewer sheets. Rebar lays a grid at the selected spacing in both directions; any individual bar run longer than one 20 ft stock length needs a lap-spliced overlap, which adds real material beyond the as-designed coverage length.
Worked Example
This example walks through your current inputs above, using the same steps as the Formula section.
Input Values Used
| Input | Value | Why it is used |
|---|---|---|
| Shape | 20 ft / 20 ft | Sets area and concrete volume |
| Thickness | 4 in | Sets volume and joint spacing |
| Reinforcement | mesh | Sets mesh sheet or rebar count |
Step 1 — Concrete Volume
| Calculation | Result |
|---|---|
| Area = Length x Width = 20 x 20 | 400 sq ft |
| Volume = Area x Thickness = 400 x 0.333 ft | 4.94 cu yd |
| Order volume = Volume x (1 + 8%) | 5.33 cu yd |
| Trucks = ceil(Order Volume / 10 cu yd) | 1 loads |
Step 2 — Base Material
| Calculation | Result |
|---|---|
| Base volume = Area x Base Depth = 400 x 0.500 ft | 7.41 cu yd |
| Base weight = Volume x Density x (1 + 15% compaction) x (1 + 8% waste) | 14.34 tons |
Step 3 — Control Joints
| Calculation | Result |
|---|---|
| Spacing = clamp(2.5 x 4, 8, 15) | 10 ft |
| Transverse joints = ceil(20 / 10) - 1 | 1 |
| Longitudinal joints = ceil(20 / 10) - 1 | 1 |
| Total joints | 2 |
Step 4 — Wire Mesh
| Calculation | Result |
|---|---|
| Rows x Cols = 10x5 ft sheets, 6" overlap, best of both orientations | 3 x 5 |
| Total sheets | 15 |
Therefore, this 20 ft x 20 ft, 4" thick driveway needs approximately 5.33 cu yd of concrete, 14.34 tons of base material, 15 mesh sheets, and 2 control joints.
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Disclaimer: This calculator provides approximate results for planning and estimation purposes only. Actual requirements may vary based on site conditions, materials, workmanship, and local building regulations. Always consult a qualified engineer, architect, or construction professional before making final decisions.