JB PARCELParking Stall Calculator
Zoning sets parking as a ratio per 1,000 square feet of building. Enter the building and the ratio to see the stalls required, how many of them have to be accessible, and how much site the parking consumes before anything else is drawn.
How this calculator works
Zoning states parking as stalls per 1,000 square feet of gross floor area for the use. Multiply the building by the ratio and round up, because a partial stall is still a stall. The ratio is the local number and it varies widely, so take it from the ordinance for the district and use rather than from a rule of thumb.
Accessible stalls are not a percentage. The 2010 ADA Standards table 208.2 is a stepped table: one accessible stall up to 25 spaces, two up to 50, four up to 100, and so on to nine at 500, then two percent of the total to 1,000, then twenty plus one for each additional hundred. One in every six accessible stalls has to be van accessible, rounded up, which means the first accessible stall is also a van stall.
Then size the land. A striped stall is about 162 square feet, but a stall is useless without the aisle that reaches it, so planning work uses 300 to 350 square feet per stall including circulation. That is the number that tells you whether the parking fits before anything else is drawn.
Compare the parking area against the site early. Parking, setbacks, and stormwater compete for the same ground, and on a small commercial site the parking requirement is usually what decides the size of the building, not the other way round.
Worked example: a 12,000 square foot medical office
Zoning requires 4 stalls per 1,000 square feet, and planning is done at 325 square feet a stall.
| Stalls required | 48 |
|---|---|
| Accessible | 2, one of them van accessible |
| Standard stalls | 46 |
| Parking area | 15,600 sf, about 0.36 acres |
On a one acre site that parking is 36 percent of the ground before the building, the setbacks, or the stormwater basin. Push the ratio to 5 per 1,000, which several medical uses carry, and it becomes 60 stalls and 19,500 square feet, at which point three accessible stalls are required rather than two.
Where the numbers come from
Accessible and van stall counts are from the 2010 ADA Standards for Accessible Design, sections 208.2 and 208.2.4. Parking ratios are local zoning and are an input on this page for that reason. Stall and aisle areas are planning figures, not code minimums, and the geometry your jurisdiction requires governs.
Questions investors ask
How many parking spaces are required per 1,000 square feet?
It is set by local zoning, not by a national standard, and it varies by use: offices often sit near 3 to 4 per 1,000, retail near 4 to 5, and medical or restaurant uses higher. Many cities have cut or removed minimums entirely. Take the ratio from the ordinance for the district the parcel is in.
How many ADA parking spaces do I need?
From table 208.2 of the 2010 ADA Standards, counted against the stalls provided: 1 up to 25 spaces, 2 up to 50, 3 up to 75, 4 up to 100, 5 up to 150, 6 up to 200, 7 up to 300, 8 up to 400, 9 up to 500, 2 percent of the total from 501 to 1,000, and 20 plus 1 per additional 100 above that.
How many van accessible spaces are required?
At least one in every six accessible spaces, rounded up. A lot with one accessible stall needs that stall to be van accessible, and a lot with 7 accessible stalls needs 2.
How much land does parking take?
Between 300 and 350 square feet per stall once the drive aisle is included, so roughly 130 to 145 stalls an acre. Striping alone would suggest 9 by 18 feet, or 162 square feet, but no stall works without the aisle that serves it.
Does the building count toward the parking area?
No. This page sizes the parking surface only. The building footprint, setbacks, and stormwater all compete with it for the same site, which is what the setback calculator and the lot coverage calculator are for.
Related calculators
Screening a real property? Pull its appraised value, assessed value, acreage, land use, and last recorded sale off the JB PARCEL parcel map and drop the real numbers into this calculator instead of guessing. Coverage runs across every county we carry.