Parking ratio

A parking ratio expresses how many off-street parking spaces a building has for each apartment. Zoning codes set minimum ratios, such as one space per unit or a schedule that varies by bedroom count, and developers sometimes provide more than the minimum if they believe tenants demand it. Recently, some jurisdictions have reduced or removed minimums, leaving the ratio to the developer's judgment.

Parking costs money in two ways. A space has a direct construction cost that rises steeply as it moves from a surface lot to a structured garage to an underground level. And a space takes land or building volume that could otherwise hold homes, which reduces the density a site can achieve. On a constrained urban lot, a parking minimum can decide whether a project has 100 units or 75.

The rent effect follows from cost. Assume a required space costs $30,000 to build in a structured garage and the ratio is one space per unit: that is $30,000 of cost per unit, or roughly $203 per unit per month under our default rent math, whether or not the resident owns a car. If the space can be rented separately, some of that is recovered; if it cannot, it is embedded in everyone's rent. We work through the full arithmetic in What a Parking Space Adds to Rent.

Parking ratios are a clear example of a rule whose cost is invisible to the people it affects. A resident without a car pays for a space they do not use, and no line on the lease says so. That is why we treat Parking as its own topic.