Residential parking requirements are typically linked to residential unit sizes and guest ratios. For example, the table below refers to the off-street parking in Costa Mesa.
In this table there is a clear relationship between unit sizes and number of parking stalls. The city of Costa Mesa requires a combination of covered and open stalls to fulfill the parking requirement, and allows for reductions based on additional availability of covered spaces and reductions in guest parking in large developments. Depending on the jurisdiction and circumstances, there may exist exemptions or approvals that allow for a reduction in parking.
While the table is descriptive, I prefer to use an excel worksheet when calculating the required covered, open, and guest parking stalls.
Santa Monica does a really great job in making its parking standards organized and readily searchable.
Standard parking space is 8′-6″ x 18′ with a 25′ aisle for a 61′ parking bay. Commercial areas may be able to reduce aisle width by increasing stall width at a ratio of 3:1 (allowing for 9′-6″ x 18′ with a 22′ aisle).
Compacts are 7′-6″ x 15′ with a 20′ aisle for a 50′ parking bay.
As an architect, I sometimes have the fun job of laying out parking stalls, and confirming whether I can fit enough for the required programs. It’s tedious work, but necessary.
What is annoying however is how obscure sometimes various cities hide their information. It’s always hidden deep in the code or on some other minor web pages. Why can’t it be simpler? (Maybe most designers will know these things by experience, but then this will serve those new to our profession)
So I’m hoping to create a single place to access this information. And spare people some time and frustration.