Brooklyn and Harlem brownstone gut renovations typically run about $450–$750 per sq ft, with many 3–4 story homes landing in the $650 k –$1.4 M + range including systems, layout changes, and façade work. The All‑Electric Buildings Act mainly targets new low‑rise buildings with permits filed on or after Dec 31, 2025 , not most standard brownstone renovations, though full system overhauls and new additions must be designed with future electrification in mind. Sidewalk shed perm

A full-floor brownstone gut renovation in NYC costs $600K–$950K depending on neighborhood, takes 5–6 months from permit to completion, and requires ALT1 permits plus LPC approval if in historic districts. Budget 25–30 business days for DOB plan review. Lead-safe demolition, MEP upgrades, structural reinforcement, and proper permit sequencing are critical to avoid violations and cost overruns.