Castle Hill-Unionport, The Bronx

Castle Hill-Unionport's median recorded building dates to 1945 — the exact boundary year this file uses to mark the start of the postwar construction boom. That timing shows up in the split: 45% of buildings on record predate 1940, and 34% date from the boom years between 1945 and 1975 that follow directly on the median's heels. Only 8% of the recorded stock has gone up since 2000, and no lots are listed inside a historic district, so the neighborhood's file reads as a straightforward two-era story rather than a layered one — a pattern shared with only a few of the surrounding files. Few neighborhoods in this cluster sit their median build year so precisely on a boundary the file itself defines, which makes this a useful reference point for reading the age columns of its neighbors.

Height on record is uniform and low: the median building rises 2 stories, and 0% of structures exceed 6 floors — not a single recorded building in the file clears that threshold. One- and two-family homes account for 70% of the land-use mix, well ahead of the 18% recorded as multi-family walk-up, with 3% of lots still listed as vacant land. Building class records track the same pattern: two-family homes make up 45% of structures, one-family homes 25%, and walk-up apartment buildings 18% — three classes that together account for nearly nine in every ten recorded structures. The overlap between the land-use file and the building-class ledger is about as close as this batch of neighborhoods gets, suggesting a fabric that has changed little in either use or form since it was built.

The roughly 3,700 tax lots here run modestly sized, with a median lot of 2,575 square feet, and the file's upper range stays contained too: one lot in ten reaches 5,150 square feet or more. Residential use covers 91% of parcels, and the file records 14,311 housing units in total. Development headroom is wide: 78% of lots carry less floor area than their district currently allows, with a median residual of 0.4 additional FAR still unbuilt — a paper figure describing capacity, not any owner's plans, and one that varies considerably from lot to lot even where the neighborhood-wide share looks uniform.

Flood exposure is limited on the current federal map, covering just 2% of lots. Castle Hill-Unionport sits among a cluster of neighboring files — Parkchester, Soundview-Bruckner-Bronx River, Soundview-Clason Point, Throgs Neck-Schuylerville, and Westchester Square all carry the same per-lot detail on these pages, down to individual tax-lot records available on PearlAudit.