GLOSSARY

Effective Supply

Effective supply is the usable share of a facility’s stalls after deducting a cushion for circulation, turnover friction, misparked vehicles, and reserved stalls, typically 85-95% of the striped count. In a parking facility:

GROSS SUPPLY · EVERY STRIPED SPACE (100%) USABLE EFFECTIVE (PRACTICAL) SUPPLY · ~85–95% CUSHION 5–15% The cushion, turnover, reserved and accessible stalls, mis-parking, and seasonal peaks, is why a lot feels full before the last stripe.
Effective supply is the share of gross spaces a facility can realistically fill, typically 85 to 95 percent. Planning to 100 percent guarantees a lot that feels full and hunts for spaces.
  • A 1,000-stall garage functions as roughly 900-950 stalls; demand analysis against the striped count overstates capacity.

Considerations

  • The cushion varies by user mix and turnover; high-turnover retail needs more. Design to effective supply, not the paint.
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