What Drives the Cost of a Six-Story Apartment Building in NYC

Why we do not publish a price per square foot

Material and labor costs move during the life of a project, and each lot in Queens or Brooklyn differs in soil, neighbors, frontage and zoning. A single figure per square foot hides the decisions that actually separate one budget from another. This guide sets out those decisions in the order a developer usually makes them, so the project team can see which ones are still open and price each one as it is settled.

The example throughout is a typical project: a lot with one or two existing houses, demolished and replaced by a six-story building of about 30 units.

Site, demolition and foundations

The work below the first floor is where budgets vary most between otherwise similar buildings. Demolition of the existing houses requires its own DOB permit. Excavation next to existing row houses or attached buildings can require support of excavation, underpinning and the special inspections that go with them, along with preconstruction surveys, monitoring, protection of party walls and notice to adjoining owners under Chapter 33 of the Building Code (opens an external site).

• Soil and groundwater conditions, which decide the foundation type and whether dewatering is needed.
• The condition and foundations of the adjoining buildings, which decide how much underpinning and monitoring is required.
• Whether the building has a cellar or below-grade parking, which sets the depth and volume of excavation.
• Utility connections, including the electric service size an all-electric building needs.

Parking is a design choice in more places than before. Under City of Yes for Housing Opportunity, adopted in December 2024, the Council adopted a multi-zone system (opens an external site) that eliminates parking requirements for new developments in Manhattan other than Inwood, in Long Island City and in parts of western Queens and Brooklyn, reduces them in areas with transit access, and keeps them elsewhere. Where parking is no longer required, leaving out a below-grade garage changes the excavation, structure and mechanical scope. The architect should confirm which zone applies to the lot.

Height thresholds and site safety

Height affects cost through site safety rules as well as through structure. Since December 11, 2024, a building of seven or more stories or 75 feet or more is a major building and needs a site safety manager or coordinator on site during all active work until the building is enclosed and the sidewalk shed is removed. A six-story building under 75 feet needs a construction superintendent, and from July 13, 2026 a superintendent can no longer be shared with another active permit. Our guide to six versus seven stories explains both rules.

A building of this height also needs a sidewalk shed: DOB requires property owners to install one when constructing a building more than 40 feet high (opens an external site). Legislation signed in April 2025 shortened the shed permit term from one year to three months (opens an external site), and the same package raised the required lighting and created new penalties for owners who do not complete work on time. The shed is a monthly cost until the façade is finished, so the speed of enclosure is a cost item in its own right.

Energy code, the air-leakage test and all-electric systems

Three energy rules shape the mechanical, electrical and envelope budget of a new building in New York City.

• The 2025 NYC Energy Conservation Code, for complete energy submissions filed on or after March 30, 2026, requires a third-party air-leakage test on all new construction, and DOB states (opens an external site) that the building cannot obtain a certificate of occupancy until the test passes. The cost is in the air-barrier details, the sealing of every penetration and the time reserved for a retest; see our guide to the air-leakage test.
• Local Law 154 requires new buildings under seven stories to be all-electric, which means heat pumps, electric hot water and electric cooking, and a larger electric service. The dates and exceptions are in our guide to the NYC and state gas bans.
• Local Law 97 (opens an external site) sets greenhouse gas emissions limits for buildings over 25,000 gross square feet, with annual reports due May 1 and stricter limits from 2030. Whether a given building exceeds that size is confirmed by the architect's area calculation. Our guide to Local Law 97 capital planning explains what the limits mean for a building after completion.

Roof requirements for solar or green roofs on new buildings are covered in our guide to Local Laws 92 and 94.

The 485-x option and the unit count

For a rental building of 6 to 99 units, 485-x Option B requires 20 percent of the units to be affordable at an average of 80 percent of AMI, for a 35-year benefit plus up to three construction years. The unit count matters at two lines: the building service prevailing wage applies at 30 or more units, and the 485-x construction wage applies at 100 or more. If the lot contained dwelling units three years before construction started, the new building must include an affordable unit for each one demolished. HPD's rules also require reasonable efforts to spend at least 25 percent of applicable costs with minority- and women-owned businesses, which affects how trade packages are bought out and documented.

These are legal and tax questions for counsel and HPD. Our guide to 485-x for buildings under 100 units summarizes the published rules.

Insurance and the scaffold law

Insurance requirements on New York construction projects are shaped to a large degree by the Labor Law. Section 240(1) of the Labor Law (opens an external site) places the duty to furnish scaffolding, hoists, stays, ladders and other devices that give proper protection to workers on all contractors and owners and their agents. The only owners excluded are owners of one- and two-family dwellings who do not direct or control the work, so the developer of a 30-unit building is covered.

For that reason, the insurance a developer requires of each trade, including the limits, any additional insured status for the owner and the general contractor, and the exclusions to avoid, should be settled with an insurance broker before buyout. A trade with SST-carded crews, a written fall-protection approach and a clean jobsite reduces exposure for everyone above it in the contract chain.

Finish package choices

Interior finishes are the part of the budget the developer controls most directly. Because a 30-unit building repeats a small number of unit types, each choice is multiplied across the building.

• Kitchens: cabinet construction, countertop material, appliance package and whether layouts repeat by line.
• Bathrooms: tile extent, vanity and fixture selections, and tub or shower configuration.
• Flooring: product type, acoustic underlayment between units and transitions.
• Doors, frames and hardware, including fire-rated openings at corridors and stairs.
• Paint, trim and closet systems, chosen for durability across future turnovers.
• Lead times: a finish that arrives late holds up punch, turnover and the TCO.

Standardizing selections by unit type, approving samples before buyout and ordering long-lead items early keep the finish package from becoming a schedule risk.

Schedule and carrying cost

Every month of construction carries loan interest, insurance, site staffing, sidewalk shed rental, utilities and, under 485-x, a construction-period benefit limited to a fixed number of years. A schedule that slips at enclosure, at the air-leakage test or at closeout adds to all of them at once. The certificate of occupancy is the last gate, and the items that hold it up are described in our guide to TCO and CO for new buildings.

Our project management service acts as a contracted owner's representative for these decisions: it keeps the schedule, tracks buyout and change orders, and follows each closeout item to sign-off. We also perform interior finish packages, punch and turnover, with electrical, plumbing and mechanical scopes coordinated through licensed partner contractors.