Concrete Ramp Calculator
Calculate concrete volume for a ramp in cubic feet, cubic yards, and 80-lb bags. Check ADA compliance, add curbs, estimate rebar, and get cost estimates.
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ft
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Concrete (cubic feet)
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Concrete (cubic yards) —
80-lb Bags (+ 10% waste) —
Extended More scenarios, charts & detailed breakdown ▾
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ft
in
Cubic Feet
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Cubic Yards —
80-lb Bags —
Professional Full parameters & maximum detail ▾
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ft
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Concrete Volume
Concrete (cubic ft) —
Concrete (cubic yds) —
80-lb Bags —
Materials
Rebar Linear Feet —
Form Board Linear Feet —
Design
Slope (%) —
Handrail Required? —
Cost
Estimated Concrete Cost —
How to Use This Calculator
- Enter the ramp length (ft), width (ft), and rise height (inches).
- See cubic feet, cubic yards, and number of 80-lb bags needed.
- Use ADA Compliant tab to check if your slope meets the 1:12 requirement and calculate landing areas.
- Use With Curbs to add volume for 6-inch curbs on both sides.
- The Professional tier adds rebar, form boards, handrail requirements, and cost estimate.
Formula
Ramp Volume = 0.5 × Length (ft) × Rise (ft) × Width (ft)
Cubic Yards = Cubic Feet ÷ 27
80-lb Bags = Cubic Feet ÷ 0.60 (add 10% waste)
Example
Example: Ramp 12 ft long, 4 ft wide, 12" rise → Volume = 0.5 × 12 × 1 × 4 = 24 cubic feet = 0.89 cubic yards = 44 bags (incl. 10% waste).
Frequently Asked Questions
- A ramp is a wedge (triangular prism). Volume = 0.5 × length × (rise/12) × width (in cubic feet). One 80-lb bag covers approximately 0.60 cubic feet of concrete.
- ADA standards require a maximum slope of 1:12 (1 inch of rise per 12 inches of run). This means a 24-inch rise requires at least a 24-foot long ramp. Steeper slopes are non-compliant for accessibility.
- ADA requires a 5-foot level landing at the top and bottom of every ramp, and an intermediate landing every 30 inches of vertical rise along the ramp. Landings must be at least 60 inches wide.
- Divide your total cubic feet by 0.60 (the yield of one 80-lb bag). Always add 10% waste. For a standard residential ramp: a 10-ft × 3-ft ramp with 10" rise needs about 1.25 cubic feet = ~3 bags.
- ADA requires handrails on both sides of any ramp with a rise greater than 6 inches. Handrails must be between 34 and 38 inches high and extend 12 inches horizontally beyond the top and bottom of the ramp.