Corner, Through & Interior Lots: Why Block Position Changes the Rules

Take one rectangular lot and place it at three positions on a block: mid-block on a single street, at the intersection, and spanning the block from street to street. Same dimensions, same district — three different sets of rules. The mid-block interior lot is the default the general rules assume: one front, two sides, a rear. The corner lot has two fronts and no true rear. The through lot has two fronts and no rear at all, only middle. Because yards and coverage attach to lot lines by their classification, the geometry of position rewrites the obligations.

On an interior lot, the rear yard runs along the rear lot line, joining the block's mid-block seam of open space. A corner lot has no rear lot line in the ordinary sense — its two street frontages typically both take front-yard treatment, and the rules handle the remaining lot lines specially. A through lot substitutes a rear yard equivalent: open area required in the middle of the lot, preserving the block-interior light the paired rear yards would otherwise have provided.

These are exactly the details that surprise back-of-envelope math. A through lot that looks like double frontage and double opportunity also owes its open area mid-lot, where it may interrupt the most natural floor plates; a corner lot that escapes the rear-yard rule may owe planting or front-yard depth on two streets instead.

Coverage tables routinely allow corner lots to cover more of their ground than interior lots in the same district. The logic is optical: an interior building draws light from one street and the block interior, while a corner building borrows sky from two intersecting streets, so a fuller footprint costs its neighbors less. The same two-street exposure is why ground-floor retail gravitates to corners and why corner buildings so often run their massing to the property lines. The allowance is a recognition of geometry, not a favor.

Lot type also governs how vehicles reach the lot. Curb cuts — openings in the curb for driveways — are regulated both by zoning and by street rules, and locations near intersections face particular restrictions for sightlines and pedestrian safety. A corner lot's apparent abundance of frontage can therefore be deceptive: the usable frontage for access may be a fraction of the total. For projects that need parking or loading, frontage arithmetic and curb-cut feasibility belong early in the analysis, not late.

Lot classification reads from the tax map's geometry: which lot lines meet which streets. Then the district's rules assign the obligations — yards per lot line class, the coverage row for the lot type, and any frontage-dependent provisions. Irregular shapes complicate classification in ways the definitions anticipate but an aerial glance does not. A PearlAudit report carries the lot's recorded geometry and frontage facts, which is where the classification question starts.