You're revising a site plan at 11pm. The permit set goes out tomorrow. You need to know how many accessible parking stalls are required. Here's the table.
The Accessible Parking Table (ADA / CBC Chapter 11B)
Both federal ADA and California CBC Chapter 11B use the same base ratio. California adds extra requirements on top — more on that below.
| Total Parking Spaces in Lot | Minimum Required Accessible Spaces |
|---|---|
| 1 to 25 | 1 |
| 26 to 50 | 2 |
| 51 to 75 | 3 |
| 76 to 100 | 4 |
| 101 to 150 | 5 |
| 151 to 200 | 6 |
| 201 to 300 | 7 |
| 301 to 400 | 8 |
| 401 to 500 | 9 |
| 501 to 1,000 | 2% of total |
| 1,001 and over | 20 + 1 per 100 over 1,000 |
Bookmark this. Print it. Tape it to your monitor. You're welcome.
Van Accessible Spaces: The Ratio Nobody Remembers
Of your required accessible spaces, at least 1 in every 6 (or fraction thereof) must be van accessible. That fraction part matters.
If you need 2 accessible spaces: 2 ÷ 6 = 0.33, round up to 1. You need 1 van accessible stall.
If you need 7 accessible spaces: 7 ÷ 6 = 1.17, round up to 2. You need 2 van accessible stalls.
Under CBC 11B-208.2.4, facilities that provide parking for outpatient medical care facilities must make all accessible spaces van accessible. If your project touches a medical office or clinic, that changes everything.
CBC Chapter 11B vs. Federal ADA: California Is Stricter
Federal ADA sets the floor. California CBC Chapter 11B raises it. When they conflict, CBC wins — and in California they usually conflict.
Key differences you'll actually hit on a site plan:
- Signage height: ADA requires the International Symbol of Accessibility. CBC adds a specific mounting height requirement (bottom of sign at 60 inches minimum above finish grade) and requires a tow-away notice sign at the lot entrance.
- Access aisle striping: CBC requires the diagonal hatching to clearly delineate the aisle — painted lines. Plan checkers will flag this.
- Vertical clearance: Van accessible routes require 98 inches (8'-2") of vertical clearance throughout the entire path of travel to the accessible stall, at the stall itself. This catches a lot of projects with parking structures or overhangs.
- Path of travel: CBC 11B-206 is more prescriptive than federal ADA about the path from the accessible stall to the accessible entrance. It has to be the shortest accessible path, any accessible path.
If you're doing permitting in California, work from CBC 11B. Pull out the federal ADA standards only when a federal agency is the client or when you're doing a self-evaluation for transition plan purposes.
Stall Dimensions
Standard accessible stall: 9 feet wide x 18 feet deep, with a 5-foot access aisle on one side.
Primary van accessible stall: 12 feet wide x 18 feet deep, with a 5-foot access aisle. Exception: 9 feet wide x 18 feet deep, with an 8-foot access aisle. The 8-foot aisle is what separates a van accessible stall from a standard accessible stall — not the stall itself.
Either configuration gives the same 17-foot total footprint. Same result, different geometry. Useful when you're tight on horizontal space, have a wider bay.
CBC 11B-502.2 allows the access aisle to be shared between two accessible stalls. So two adjacent accessible spaces can share one 5-foot aisle (or one 8-foot aisle if both are van accessible). That's the most space-efficient layout when you need to cluster your accessible parking.
Where to Put Them
This is the one that generates the most redlines: accessible spaces must be on the shortest accessible route to the accessible building entrance, not the main entrance, and the closest point of the building.
If your building has multiple accessible entrances, accessible parking is required to be dispersed among them in proportion to the number of parking spaces serving each entrance (CBC 11B-208.3.1).
That means a big-box retail project with an entrance on the north and south sides needs accessible stalls near both. You can't cluster all your accessible parking on the south side because that's where you had room.
If a parking structure is involved, the accessible stalls closest to the elevator core are the right call —, verify the accessible path from elevator to entrance doesn't have grade issues.
The Slope Requirement Everyone Forgets
Accessible stalls and their access aisles must have slopes no greater than 2% in any direction (CBC 11B-502.4).
Not 2% running slope and 2% cross slope. Two percent maximum in any direction, period. That means your diagonal slope (the resultant of running and cross combined) also has to stay under 2%.
On a sloped site, this is the hardest constraint to meet. A lot of civil engineers rough in accessible stalls at the top of the parking field where the grade is favorable and call it done., if the rest of the site plan shifts during design development, those stalls end up in a location that no longer meets the 2% rule and nobody catches it until the site inspection.
Build the accessible stall locations into your grading model early. Don't treat them as a markup afterthought.
Common Mistakes We See on Permit Submittals
1. Miscounting total spaces. The ADA/CBC table is based on the total number of spaces in the facility — not the total in a single lot if the facility has multiple lots. If you have three parking areas serving one building, add them all up. Then apply the table to the combined total.
2. Forgetting the van accessible ratio. Most plans show the right number of accessible stalls, mark all of them as standard. That's a correction notice waiting to happen. Always label which stalls are van accessible and verify the 1-in-6 math.
3. Not accounting for future phases. If a project is phased, accessible parking must be provided for each phase as built. You can't defer all accessible parking to Phase 2 and leave Phase 1 with none. Plan checkers in the Bay Area particularly watch for this on EIR-conditioned projects where phasing is defined.
4. Ignoring path of travel costs. In California, when you add or alter parking, you may trigger a path of travel obligation under CBC 11B-202.4. If the accessible route from the stalls to the entrance has issues — cracked sidewalk, excessive cross slope, no curb ramp — those have to be corrected up to 20% of the valuation of the primary work. Run this analysis before you finalize the parking layout, not after the contractor budget is set.
A Quick Checklist Before You Submit
- Total space count is correct and includes all lots serving the facility
- Accessible stall count matches the table
- Van accessible count is 1 per 6 accessible (or fraction thereof), labeled on plan
- Access aisle widths: 8 ft for van, 5 ft for standard
- Accessible stalls located on shortest accessible route to accessible entrance
- Stall and aisle slopes verified at 2% max in all directions (check your grading plan)
- 98-inch vertical clearance confirmed on path of travel (if structured parking)
- Signs comply with CBC 11B-502.6: ISA symbol, mounting height, tow-away notice at entrance
- Diagonal hatch striping shown on plan per CBC requirements
- Path of travel analysis complete if project triggers 11B-202.4
When to Call Us
The table is the easy part. Where it gets complicated is phased projects, facilities with multiple buildings, shared parking agreements, or anything with structured parking and vertical clearance constraints. We do site planning across California — from small infill parcels in Oakland to large-format retail in Sacramento — and accessible parking layout is a routine part of our permit coordination work.
If you're mid-design and something isn't adding up, give us a call. We'd rather look at it early than after you've got a correction notice.
For projects heading into construction, our construction administration team can verify accessible stall compliance during site observations, before the inspector gets there.
