If you’re working on a curb ramp project in Solano County and need a fast ADA compliance reference, this checklist covers the criteria that matter. For concrete supply companies in Solano County and across the North Bay, Stevenson Supply carries the materials to get this work done right, from forming supplies and concrete accessories to detectable warning tiles and traffic control.
Use this as a field guide. Always verify requirements against your project’s governing documents, local agency amendments can override state and federal minimums.
Before you form anything, confirm which standard governs the project. Getting this wrong costs more than the pour.
Required on state highway projects and most federally funded work. These plans typically require a maximum running slope of 6.67% (1:15), which is stricter than the federal ADA minimum of 8.33% (1:12).
Applies to commercial and publicly funded projects not under Caltrans jurisdiction. CBC 11B-406 covers curb ramps in full.
The federal baseline. California’s CBC is generally stricter; where they conflict, CBC governs on California projects.
Cities and counties often have their own adopted standard plans. Check with the agency before design.
Heads Up: On a project where both Caltrans and CBC could apply, use the stricter requirement for each element. When in doubt, ask the engineer of record.
A sloppy layout means a failed inspection. These items should be confirmed before forming begins.
Perpendicular (single or dual), parallel, or blended transition. The type is typically called out in the project plans or standard specs.
Stevenson Supply stocks Spectra and Pro Shot single and dual slope lasers, plus grade rods and receivers, for accurate grade confirmation on site.
Cross slopes on sidewalks, gutters, and street approaches affect your ramp geometry. Survey them before you design the ramp layout.
Aervoe aerosol marking paint is stocked at both Stevenson locations. Mark the ramp footprint, landing boundaries, and DWT placement zone before forming.
The ramp and landing must drain without ponding. Max cross slope of 2% in any direction at the landing keeps water moving.
Pro Tip: Confirm your slopes on the existing adjoining surfaces first. If the adjacent sidewalk or gutter already runs steeper than 2% cross slope, your ramp geometry gets complicated fast. Catch it before forming.
This is where most ramps fail inspection. Every measurement below is a pass/fail threshold.
Max 8.33% (1:12) per federal ADA. Caltrans Standard Plans require max 6.67% (1:15) on state projects. Check which governs.
Max 2.0% (1:50). No exceptions.
Max 2.0% in any direction.
Max 10.0% where the flare is within the pedestrian circulation path. If the flare is outside the pedestrian path, no maximum applies under ADA, but verify with CBC 11B.
The surface immediately beyond the bottom of the ramp cannot exceed 5% in the direction of ramp travel (ADA) or as specified by the governing standard.
Heads Up: A 2% cross slope sounds like plenty of tolerance. On a 5-foot-wide ramp, that’s just over 1 inch of fall across the full width. Measure carefully. Stabila digital levels are available at both Stevenson locations
Landings must be clear of obstructions and within slope limits. These are minimum dimensions.
Minimum 4 ft wide x 4 ft long, clear of door swings, utility covers, and other obstructions. CBC 11B-406.5.3 requires 48 inches minimum in the direction of travel.
Minimum 4 ft wide x 4 ft long. Must be within the street or gutter, not on the ramp surface itself.
Minimum 5 ft x 5 ft (60 in. x 60 in.) where the accessible route changes direction at the landing.
Parked cars, signal poles, sign posts, and drainage inlets frequently eat into landing space. Confirm clear dimensions in the field, not just on plans.
Vertical changes at transitions to adjoining pavement: max 0.5 in. with a bevel, max 0.25 in. without a bevel.
Required at every curb ramp where a pedestrian access route meets a vehicular way. No exceptions on California public projects.
Domes must be 0.9 in. center-to-center spacing, 0.2 in. height, 0.9 in. base diameter. These are per ADA and CBC 11B-705.
Minimum 24 in. in the direction of pedestrian travel, measured from the back of curb.
Full width of the ramp, excluding flares.
Federal yellow (safety yellow) is standard on California public right-of-way projects. Confirm the agency requirement.
Cast-in-place, surface-applied composite panels, and retrofit tile options are all used depending on project type. Surface-applied panels are common on retrofit work; cast-in-place is typical on new construction.
Pro Tip: DWT placement gets rejected when panels are set too far from the curb edge or too far back from the flow line. The 24-inch depth is measured from the back of curb, not from the ramp break point. Measure twice before setting tile.
Accurate forming is what makes the grade measurements hold. Shortcuts here show up at inspection.
Stocked at Stevenson Supply for clean, accurate edge control on concrete flatwork and curb applications.
Curing compounds, joint sealants, and related accessories available at both locations.
For projects with spec requirements on admixtures, retarders, or curing compounds.
The surface texture on the ramp must not impede mobility device use. Broom finish perpendicular to the direction of travel is standard. Coarse or irregular finishes that catch wheels or crutch tips will fail accessibility review.
Hot and cold weather curing affects long-term surface integrity. Follow spec requirements for curing compounds or wet curing, especially in summer heat or winter conditions in Solano County.
Stocked at Stevenson. Use rebar cap tips on all exposed rebar per Cal/OSHA requirements.
Heads Up: The ramp surface texture matters for ADA compliance. A finish that feels aggressive underfoot can still fail if a wheelchair or walker catches on it. Spec usually calls out finish requirements, don’t assume a standard broom finish is always acceptable.
On public right-of-way, your traffic control plan is a separate deliverable. Have your materials staged before work starts.
Pro Tip: Your traffic control plan (TCP) on municipal projects is reviewed and approved separately from your construction plans. Confirm approval before mobilizing, unapproved TCPs can shut down a pour.
Document before traffic resumes. Once the surface is in use, it’s much harder to prove compliance.
For curb ramp work specifically, Stevenson Supply & Tractor Co. stocks:
Delivery is available throughout Solano County for contractors who need materials on site without the trip. Contact our sales team for delivery schedules.
Stevenson Supply’s Vallejo location has the supplies you need to do the job right. Whether you need detectable warning tile, forming supplies, concrete accessories, or a full traffic control package, our team can put together what your job requires.
Reach out to Stevenson Supply & Tractor Co today!
📞 Call us: (707) 575-3335
President/CEO
Kent Stevenson is the owner and president of Stevenson Supply & Tractor Co., a family-owned equipment and supply company serving Sonoma County and the North Bay agricultural community since 1967. Under Kent’s leadership, the company has expanded from a small tractor dealership into a trusted regional provider of agricultural equipment, hardware, fencing, and repair services.
Kent is known for his deep agricultural knowledge, hands-on approach, and commitment to serving the local farming and vineyard community. His business philosophy blends old-fashioned service with modern efficiency, ensuring every customer—from homeowners to commercial growers—receives honest guidance and reliable equipment solutions.
Stevenson Supply continues to reflect the values Kent grew up with: hard work, integrity, and dedication to supporting the people who keep Sonoma County growing.
