Enter your ramp's run, width, and rise to instantly calculate concrete volume in cubic yards, slope ratio, ADA compliance status, and total cost estimate.
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ADA / ABA 2010 Standards verified
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Imperial & metric supported
✓ Slope ratio & percent grade✓ ADA compliance check✓ Cost estimator included✓ Last verified May 2026
Reviewed by the AllConcreteCalculator.com editorial team — slope formulas and ADA requirements cross-checked against 2010 ADA Standards for Accessible Design, May 2026.
Enter Your Ramp Dimensions
Horizontal distance from bottom to top of ramp. ADA max: 30 ft (360 in) per run before a landing.Please enter a valid run greater than 0.
Clear width between handrails. ADA minimum: 36 inches (3 ft).Please enter a valid width greater than 0.
Vertical height gained. ADA max: 30 inches per run before a landing.
Please enter a valid rise greater than 0.
Minimum 4 in for foot traffic, 5–6 in recommended for ramps. Measured perpendicular to the slope surface.
Please enter a valid thickness greater than 0.
Add 10% for standard ramps. Use 15% for curved or tapered ramps.
$
Leave blank to skip cost estimate. US average: $100–$150/yd³ for ready-mix.
Results appear instantly. No sign-up required.
Your Ramp Concrete Estimate
Concrete Volume (with waste)
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Cubic Yards (yd³)
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Cubic Feet (ft³)
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Cubic Meters (m³)
Slope Analysis
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Slope Ratio (H:V)
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Grade (%)
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Angle (°)
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—Surface Area (ft²)
—Slope Length
—Thickness
—Waste Factor
Estimated Material Cost
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Concrete material cost only. Add labor ($4–$8/ft² for ramps), handrails, forming, sub-base, and finishing for a full project budget. Use our Full Project Estimator for a complete breakdown.
ADA 2010 §405: Max slope 1:12 (8.33%), max rise 30 in per run
How to Use This ADA Ramp Calculator
Measure the run — the horizontal distance.
Set a level string line from the high end of where your ramp will start to the low end, then measure the horizontal distance along the ground. This is your run. Do not measure along the slope — the calculator uses horizontal run and vertical rise separately to compute the true sloped length for you.
Measure the rise — the vertical height change.
Use a level and tape measure to find the exact vertical drop between the high point and the low point of the ramp. This is the single most important dimension for ADA compliance: the slope ratio (1:12 max) is determined entirely by rise divided by run. A 1-inch error here can push you out of compliance.
Enter width and slab thickness.
Width is the clear dimension between handrails, not the overall slab width. ADA minimum is 36 inches. For slab thickness, 5 inches is the standard for pedestrian ramps — use 4 inches only if the ramp is lightly used and well-supported, and 6 inches for heavier applications.
Review the slope analysis and compliance indicator.
The calculator shows your slope ratio, percent grade, and an immediate ADA compliance check. Green means your ramp meets the 1:12 maximum slope and 30-inch maximum rise limits. Yellow means one limit is borderline. Red means you need to increase the run before pouring — adjusting dimensions now costs nothing; tearing out non-compliant concrete does.
⚠ Pro Tip: Always design your ramp run to achieve a slope between 1:16 and 1:20 where space allows — even though 1:12 is the ADA maximum. Steeper ramps are technically compliant but much harder to self-propel in a wheelchair. The extra horizontal run costs almost nothing in concrete and dramatically improves usability.
ADA Ramp Concrete Volume Formula
A ramp is not a flat slab — the concrete volume is calculated along the true sloped surface, not the horizontal footprint. Here is the step-by-step process:
Step
Formula
Example (60 in run, 5 in rise, 48 in wide, 5 in thick)
1. Convert to feet
inches ÷ 12
Run = 5 ft, Rise = 0.417 ft, Width = 4 ft, Thick = 0.417 ft
Volumes include 10% waste. Thickness = 5 in, width = 48 in. For different dimensions, use the calculator above.
What Slope Does My ADA Ramp Need?
Slope is the single most regulated dimension on a concrete accessibility ramp. The 2010 ADA Standards for Accessible Design (Section 405) are prescriptive — there is no engineering discretion for exceeding the limits. The table below summarizes the key slope thresholds every contractor must know.
ADA ramp slope categories and compliance status.
Slope Ratio (H:V)
Grade (%)
ADA Status
Use Case / Notes
1:20 or shallower
≤ 5.0%
✓ No handrails required
Considered a walking surface, not a ramp per ADA
1:16 to 1:20
5.0–6.25%
✓ Compliant — Preferred
Easiest to self-propel; best for heavy wheelchair use
1:12 to 1:16
6.25–8.33%
✓ Compliant
Standard ADA ramp; handrails required
Exactly 1:12
8.33%
⚠ At the Limit
Maximum allowed; no tolerance for construction error
1:10 to 1:12
8.33–10%
✗ Non-Compliant
Exceeds ADA maximum; requires redesign
1:8 or steeper
≥ 12.5%
✗ Non-Compliant
Dangerously steep; not permissible under ADA/ABA
Design to 1:16 or shallower whenever your site allows it. The ADA maximum of 1:12 is a hard legal limit, but ANSI A117.1 and ADAG guidance consistently note that steeper ramps significantly increase the effort required for manual wheelchair users. The extra concrete to achieve a shallower slope is almost always worth it.
Common Mistakes When Building Concrete ADA Ramps
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Measuring slope along the surface instead of the horizontal run.
The ADA specifies slope as rise divided by horizontal run — not the sloped surface length. If you tape-measure along the ramp surface and use that as the "run," you will calculate a flatter slope than what actually exists and may pour a ramp that fails inspection. Always measure the horizontal distance separately from the vertical rise.
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Ignoring cross-slope.
The ADA limits cross-slope (the slope perpendicular to the direction of travel) to 1:48 (2.08%). A ramp that is perfectly compliant lengthwise but tilted side-to-side will fail accessibility inspection and cause wheelchairs to drift dangerously. Screed and finish the surface with a level — not just the grade stakes — before the concrete sets.
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Forgetting landing pads at the top and bottom of the ramp.
ADA §405.7 requires a level landing (≤1:48 slope in any direction) at the top, bottom, and any change of direction. These landings are separate concrete pours and are not included in the ramp volume calculation — always add them to your material estimate. Minimum landing size: 60 inches × 60 inches.
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Pouring a slab thinner than 4 inches.
Ramp slabs carry dynamic point loads from wheelchair casters — a thin slab cracks faster than a flat walkway of the same thickness. Minimum 4 inches for light residential use, 5 inches is the practical standard for any public or commercial application, and 6 inches should be used anywhere vehicle overrun is possible.
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Skipping rebar or using wire mesh alone on steep grades.
Wire mesh controls shrinkage cracking but does not provide structural tension reinforcement on a sloped pour. On any ramp steeper than 1:20, install #4 rebar on 12-inch centers both ways — the slab is effectively a beam spanning between grade breaks, and steel is the difference between a durable ramp and one that cracks within two winters.
Frequently Asked Questions
The 2010 ADA Standards for Accessible Design (Section 405.2) set the maximum running slope at 1:12, which equals 8.33% grade. This means for every 1 inch of vertical rise, there must be at least 12 inches of horizontal run. A ramp also cannot exceed a 30-inch total rise per run — after 30 inches of rise, a level landing of at least 60 × 60 inches must be provided before continuing with another ramp run. Cross-slope (side-to-side tilt) must not exceed 1:48 (2.08%) in any direction.
ADA Section 405.5 requires a minimum clear width of 36 inches between handrails (or between the handrail and the edge of the ramp surface). This is a minimum — for high-traffic locations, commercial buildings, or ramps used by power wheelchairs, 48 inches (4 feet) or wider is strongly recommended. The clear width measurement applies to the usable pathway, not the overall slab width, so account for any handrail posts that intrude into the surface width when designing your form dimensions.
Yes. ADA Section 405.8 requires handrails on both sides of any ramp run with a rise greater than 6 inches. Handrails must be continuous along the full length of each ramp run, extend 12 inches horizontally beyond the top landing, and extend 12 inches plus the horizontal projection of the ramp slope beyond the bottom landing. Gripping surfaces must be between 1.25 and 2 inches in diameter and mounted 34–38 inches above the ramp surface. Residential ramps built for a single-family homeowner may follow less stringent local code — check with your AHJ (Authority Having Jurisdiction).
Multiply your rise by 12 to get the minimum ADA-compliant run at 1:12 slope. For example, a 7.5-inch rise requires at least 90 inches (7.5 ft) of run. For a more comfortable 1:16 slope, multiply by 16 instead (7.5 × 16 = 120 inches). For 1:20 slope (which requires no handrails and is considered a walking surface), multiply by 20. Always round up to the next inch and add a margin — construction tolerances mean a ramp designed to the exact minimum often measures non-compliant after the pour due to subgrade settlement or forming imprecision.
Specify a minimum of 3,500 PSI for any exterior accessibility ramp. In freeze-thaw climates (USDA Hardiness Zones 1–6 and many Zone 7 areas), use 4,000 PSI with 5–7% air entrainment — the entrained air bubbles give the concrete room to accommodate freeze-thaw expansion and dramatically reduce surface scaling. A low water-cement ratio (0.45 or lower) also improves durability. For salt-exposed ramps near coastal areas or where de-icing chemicals will be used, 4,500 PSI with air entrainment and a low w/c ratio is the minimum to specify.
An ADA ramp (covered by Section 405) connects two different floor or ground levels and typically has a rise greater than 6 inches. A curb ramp (covered by Section 406) is a short ramped surface built into or adjacent to a curb, providing a transition from sidewalk level to street level. Curb ramps have different dimensional requirements — maximum slope of 1:12, no maximum rise (since curb height is fixed), and require detectable warning surfaces (the truncated dome tiles you see at crosswalks). This calculator covers full ramps; curb ramp volumes are typically much smaller and calculated as part of a combined sidewalk pour.
Almost always yes for commercial, public, or multi-family residential applications. Building departments require permits for structural concrete work, and ramps connecting to a building entrance or serving public accommodations are subject to ADA and local building code requirements. For single-family residential ramps, permit requirements vary by municipality and the ramp's purpose — a ramp serving a homeowner with a disability may qualify for expedited permitting under fair housing provisions. Always verify with your local Authority Having Jurisdiction before pouring. Unpermitted ramps that fail accessibility inspection may need to be removed at the property owner's expense.
ADA Section 402.3 requires ramp surfaces to be stable, firm, and slip-resistant. For concrete, a medium broom finish applied perpendicular to the direction of travel is the standard. A smooth trowel finish is not acceptable — it becomes dangerously slippery when wet. Exposed aggregate finishes are acceptable if the aggregate is well-embedded and does not create a bumpy surface that interferes with wheelchair caster movement. Avoid large or angular aggregate in the top surface. Grooves cut perpendicular to travel are also an acceptable texture treatment for existing surfaces that lack adequate slip resistance.
Detectable warning surfaces — the truncated dome patterns you see at crosswalks — are required by ADA Section 705 at locations where a pedestrian path meets a vehicular way. They are required at curb ramps and blended transitions at crossings, but are generally NOT required at the top or bottom of building entrance ramps unless those ramps directly abut a vehicle travel lane. The most common material is cast-in-place concrete with dome molds, surface-applied polymer panels, or precast concrete pavers. Check with your local transportation department for specific color and material requirements — many jurisdictions require high-contrast colors (yellow or red) that differ from the surrounding pavement.
A professionally installed concrete ADA ramp typically costs $1,500–$5,000 for a residential single-run ramp, and $3,000–$15,000 or more for commercial ramps with multiple runs, landings, handrails, and detectable warning surfaces. Concrete material costs represent only $200–$600 of that total for most residential ramps — the majority of the cost is labor (forming, pouring, finishing), handrail fabrication and installation, sub-base preparation, and permitting. Galvanized steel handrails alone can run $400–$1,200 depending on length and style. Always get at least three competitive quotes from licensed concrete contractors and verify they have experience with accessible design requirements.
