Concrete Slab Cost Calculator

Concrete Slab Costs by Project Type

Concrete slab pricing varies by project type because each has different size norms, thickness requirements, and finishing complexity.

Project Type	Typical Size	Thickness	Installed Cost
Patio	12×12 to 20×20 ft	4 in	$4–8/sq ft
Driveway	10×20 to 12×60 ft	4–5 in	$5–10/sq ft
Garage floor	20×20 to 24×30 ft	4–6 in	$4–9/sq ft
Sidewalk	4×20 to 6×60 ft	4 in	$6–12/sq ft
Foundation slab	Full footprint	4–6 in	$4–7/sq ft

Sidewalks cost more per square foot because they are narrower — more edge work per area — and often require more reinforcement per linear foot.

How Thickness Affects Cost

Each additional inch of thickness adds approximately $0.75–1.25 per square foot in material cost, plus minor labor increases for the heavier pour.

Thickness	Concrete Per 100 sq ft	Material Cost (100 sq ft)	Typical Use
3 in	0.93 cu yd	$150–225	Light foot traffic only; not recommended for vehicles
4 in	1.23 cu yd	$195–295	Standard residential — patios, walkways, garage floors
5 in	1.54 cu yd	$245–370	Heavier vehicles, occasional truck traffic
6 in	1.85 cu yd	$295–445	Heavy loads, commercial, freeze-thaw climates

Going from 4 to 6 inches adds roughly $100–150 in material cost per 100 sq ft. For most residential projects, 4 inches is correct — only upgrade to 5–6 inches for driveways that regularly see heavy vehicles.

Labor vs. Material Breakdown

For a professionally installed residential slab, costs split roughly 60% labor and 40% materials.

Cost Component	Share	Per sq ft (typical)
Concrete materials	~30%	$1.50–2.50
Site prep and forms	~15%	$0.75–1.50
Reinforcement (rebar or mesh)	~10%	$0.50–1.00
Labor (pour and finish)	~45%	$2.25–4.00
Total installed	100%	$5–9

Labor dominates because concrete work is time-sensitive and physically demanding. A crew of 3–4 can pour and finish a 400 sq ft slab in 4–6 hours, but that's 12–24 labor hours total at $40–70/hour.

Regional Cost Variation

Installed concrete slab prices vary significantly by region, driven primarily by local labor rates.

Region	Typical Installed (4-in slab)
Northeast (NY, MA, CT)	$7–12/sq ft
West Coast (CA, WA, OR)	$7–11/sq ft
Midwest	$5–8/sq ft
Southeast	$4–7/sq ft
Mountain West	$5–9/sq ft

Material costs (concrete, rebar, gravel) are relatively consistent nationally. Labor is the variable. In high-cost metros, always get 3+ bids — variance between contractors is substantial.

What's Included (and What's Not) in a Contractor Quote

A complete slab installation quote should include: excavation to depth, compacted gravel base (4–6 inches), forms (set and remove), reinforcement (rebar or wire mesh), concrete materials and delivery, placement and finishing labor, and cleanup.

Items often not included by default:

• Permits — typically $50–200 for residential pours
• Demolition of existing concrete — add $2–4/sq ft
• Decorative finishes — stamped, colored, or exposed aggregate add $3–8/sq ft
• Sealing — recommended for driveways, adds $0.50–1.50/sq ft
• Soil stabilization for poor subgrade — varies by conditions

Always confirm inclusions in writing before signing.

DIY vs. Hiring a Contractor

DIY concrete work saves 50–60% on labor but has real limits.

DIY makes sense when:

• Volume is under 1 cubic yard (about 45 bags of 80-lb mix — a small patio or shed base)
• You have 3+ helpers available for the day
• The finish quality and long-term performance are less critical

Hire a contractor when:

• Volume exceeds 1 cubic yard (ready-mix delivery is more practical and often cheaper)
• The project is structural (driveway, garage floor, foundation)
• Surface finish quality matters
• Local code requires a permit

For a detailed comparison, see our DIY vs. Contractor guide and concrete cost per square foot guide.