Design Professional Requirements: Commercial, Mixed-Use Buildings (Alterations)

Applicability of Code and Zoning

An Alteration project could be filed for review under either the current Codes, the 2014 NYC Construction Codes, Administrative (AC), Building Code (BC), Plumbing (PC), Fuel Gas (FGC), and Mechanical Codes (MC), or under Prior Codes, such as the 1968 Code, 1938 Code or earlier Codes, depending on the age of the existing building; reference AC 28-101.2. It is the responsibility of the Registered Design Professional to date the building to determine the applicable Codes.

Flood plains, BC Appendix G, must be considered when performing Alterations.

For example, the 2014 Code must be used for some accessibility requirements, certain renovation work of mechanical, plumbing, sprinkler, fire protection and/or fuel gas systems, specific building elements such as security grilles, handrails, guards, roofs, etc., and certain kinds of structural work. Additionally, Alteration work must comply also with the current NYC Energy Conservation Code, NYC Electrical Code, NYC Fire Code and other applicable local laws. The following Reference Guides provide instructions:

In flood plains, BC Appendix G must be considered when performing alterations.

A majority of the chapters in the Construction Codes, and prior codes, may be needed for a Commercial Building Alteration project.

*Note: The following is a list of key zoning, Code and other regulations that may be relevant in the project design, it is not comprehensive.*



Project Element

Applicable Code and Regulations

Current Code*

Prior Codes





2014 AC 28-101.4.5 and Administrative Code

2014 AC 28-101.4.3 -Optional Use of 1968 Code and AC 28-101.4.5

2014 AC 28-101.4.3, AC 28-101.4.5, and 1968 AC 27-114


2014 BC Chapter 11, and BC Appendix E, BC Appendix N, and BC Appendix P

Building Heights & Areas

BC Chapter 5

AC 27-293 through AC 27-315

Article 5

Construction Types

BC Chapter 6

AC 27-269 through AC 27-287

Article 4


BC Chapter 10 and BC Appendix S

AC 27-354 through AC 27-396.6

Article 7


2014 BC Chapter 30 and BC Appendix K

Fire Protection

BC Chapter 9, Appendix Q

2014 AC 28-315.2, 2014 BC Chapter 9,and Appendix Q

Flood Resistant Ratings

BC Chapter 7

AC 27-318 through AC 27-353.3

Article 11

Flood Resistant Construction

2014 BC Appendix G

Interior Environment

BC Chapter 12, BC Appendix R, MC Chapters 4 through 6, and MC Chapter 9

AC 27-725 through AC 27-770

1938 BC Article 6, 1938 Article 12, and 1938 Article 15

Interior Finishes

BC Chapter 8

AC 27-348(c) and AC 27-351

Sub-Article 9 of Article 11


BC Chapter 14, BC Chapters 19 to 26

Subject to applicable provisions of the 2014 BC and 1968 AC 27-600 through AC 27-651

Subject to applicable provisions of the 2014 BC and 1938 AC Article 8, and Article 19

Roof Assemblies and Rooftop Structures

BC Chapter 15

Subject to applicable provisions of the 2014 BC and 1968 AC 27-338

Subject to applicable provisions of the 2014 BC and 1938 AC 26 Article 11

Safeguards During Construction

2014 BC Chapter 33

Structural, Soils and Foundation

2014 BC Chapter 16 and Chapter 18

2014 BC 1601.2 and 1968 AC 27-580 through AC 27-724

2014 BC 1601.2 and 1938 AC 26 Article 9

Use and Occupancy Classification

BC Chapter 3

AC 27-234 through AC 27-268

Article 4 and Article 13

Other Guidelines


See Renovation Antenna Guidelines


See Building Systems Boiler Guidelines

Building Pavement Plan

See BPP - Alteration Project Guideline

Construction Equipment

See Construction Equipment Guidelines (Scaffold, Hoists, Chutes, Fences, Sidewalk Sheds, Mechanical Construction Equipment)

Curb Cuts

See Renovation Curb Cut Guidelines


See Partial Demolition Guidelines

Emergency Power Backup Systems

See Building Systems Emergency Power Guidelines


See Building Systems Mechanical Guidelines


See Building Systems Plumbing Guidelines


See Renovations: Sign Guidelines

Solar Panels

See Building Systems Solar Guidelines


See Building Systems Sprinkler Guidelines


See Building Systems Standpipe Guidelines

Swimming Pools

See Outdoor Swimming Pools Guidelines

* Note: New applications for buildings erected under the 2008 Code must comply with the 2014 Code, as required by AC 28-101.4 & AC 28-102.4.3.
** Note: Your building may be governed by a Code prior to 1938 based on the Code at the time it was built.


A Commercial/Mixed Use alteration project may require compliance with the following sections of the Zoning Resolution:

Use Regulations

  • Commercial buildings, establishments and/or uses are permitted in C1 through C8 districts and/or such commercial district overlays in residential zoning districts, M1, M2 and M3 zoning districts, and several other special zoning districts. See ZR 32-00 through ZR 32-50 and subsections.
  • Accessory uses (ZR 12-10 Accessory Use), such as areas for off street parking or loading berths, storage, mechanical and/or electrical spaces, etc.
  • Non-conforming use(s) per ZR 52-00

Bulk Regulations

Mixed Buildings

  • If Mixed Building, as previously defined, see modifications of bulk regulations outlined in ZR 35-00 through ZR 35-60 and all subsections
  • Residential Alteration Guidelines (3 or more dwelling unit buildings, or 1 & 2 family buildings)
  • If residential portion of Mixed Building is being enlarged/converted, and located on a non-complying lot, see ZR 23-32, ZR 23-33, and ZR 54-30.

Commercial Regulations

  • Floor Area (ZR 33-10 and subsections)
  • Yards and Courts (ZR 33-20, ZR 33-30 and ZR 33-50 and subsections), including permitted obstructions
  • Height and Setback, Base Plane, Rear and Side Setbacks (ZR 33-40 and subsections), including permitted obstructions
  • Any permitted vertical enlargements and construction equipment projections in any Flight Obstruction Areas shall comply with ZR 61-10 and ZR 61-20
  • Non-complying bulk per ZR 54-00

Lot Area and Width

  • No limitations on lot area and width for buildings with commercial and/or community facility uses

Special Purpose Districts

If enlargement or conversion occurs within a Special (and Sub) District, see modifications of use, bulk, parking, and other zoning regulations outlined in ZR Articles VIII through XIII.

Little (E) Designations

  • An (E) designation provides notice of the presence of an environmental requirement pertaining to potential hazardous materials contamination, high ambient noise levels or air emission concerns on a particular tax lot.

Scope of work subject to Office of Environmental Remediation (OER) approval:

  • Potential hazardous material contamination: for excavation or any soil disturbing in a lot with (E) designation
  • Air quality impacts: for renovation that involves ventilation or exhaust system in a lot with (E) designation in a lot with E designation
  • Noise quality impacts: for exterior work in a lot with (E) designation

(Refer to BB 2014-026, ZR 11-15, ZR Appendix C Table 1, and Table 2)

Permitted Obstructions

  • Permitted yard obstruction (ZR 33-23)
  • Building height and setback (ZR 33-40 and subsections)
  • Obstructions beyond height limit (ZR 33-42)

Parking and Loading Regulations

  • Location, Area and Number of Parking Spaces (ZR 36-20, ZR 36-40 & ZR 36-50 and subsections)
  • Location and Size of Curb Cuts (ZR 36-58)
  • Loading Berths, locations and quantity (ZR 36-60 and subsections)

Bicycle Parking Regulations

Street Trees

  • Street trees required in all conditions (ZR 33-03)

Urban Design Regulations

  • Special regulations for parking lots (ZR 37-90)
  • Open areas for public use, such as arcades, pedestrian ways, and public plazas (ZR 37-40 through 37-80)
  • Streetscape, alignment of street walls (ZR 37-30 and subsections)
  • Open areas (ZR 37-60)
  • Notice to emergency services of new building on a private street, unmapped street or mapped street that is not open as per OPPN 7/97)

Waterfront Area or Block

Flood Hazard Areas

If enlargement or conversion occurs within a flood hazard area, see modifications of bulk, parking, use and other zoning regulations outlined in ZR 64-10 through, and all subsections.

Other Regulation(s) for Reference

  • BB 2009-008 – Clarifies airport flight path requirements with respect to building heights. Reference ZR 61-30 and ZR 73-66
  • BB 2009-030 – Clarifies the level at which a residential rear yard is required for a mixed building when applying ZR 35-53 to modify rear yard requirements
  • BB 2010-013 – Establishes the allowance to obtain a final Certificate of Occupancy for a Mixed Use Building within a vacant space
  • BB 2017-006 – Clarifies conditions under which an addition, alteration and renovation or repair of a building envelope would not need to comply with NYCECC R501.1 & C501.1
  • BB 2013-010 – Clarifies use group and associated conditions allowed for Yoga studios
  • BB 2016-008 – Clarifies where wheelchair platform lifts may be installed in a Prior Code building
  • BB 2016-012 – Clarifies how floor surface area is calculated with respect to AC 28-101.4.5

When required by the project scope of work, the alteration must also comply with the rules, regulations, laws and codes of other City agencies, such as the NYC Fire Department (FDNY), NYC Transportation (DOT), NYC Landmarks Commission, NYC Transit (MTA), Department of Environmental Protection (DEP), and others.

Guidelines for Submission of Alteration Project Plans

Prior to preparing the design documents and construction drawings, the Registered Design Professional must perform a pre-design review that analyzes all of the existing building elements, systems and other components affected by the proposed scope of work, to verify a code compliant renovation of the building. Based upon the complexity and scale of the project, the information provided on the drawings must clearly describe all of the work required for the code compliant execution and completion of the project per AC 28-104 or 2014 BC 107.2.

The Department’s guidelines, provide an organized approach for the preparation of construction documents, as outlined in the following section, will facilitate the plan review process. Drawings shall clearly indicate existing condition, proposed condition and any area affected by the scope of work.

Complete Submission of Construction Documents

Construction drawings should represent the entire scope of work, including multiple disciplines such as architectural, structural, plumbing, electrical, mechanical, and others. There must be close coordination between all disciplines for the proposed scope of work to ensure code compliance; reference AC 28-104.7 and BC 107.2, BC 1603 and Plan Examination Guidelines – Minimum Requirement for Review if Design Drawings, Revised 3-10-2014.

A complete submission of drawings should include:

  • Construction Documents. Drawings necessary to convey essential information such as floor layouts, elevations, schedules and details. The applicable Building Codes and notes should be stated on the drawings as required to demonstrate Code and Zoning compliance. Where essential to clarify overall layouts and details, a scale should be included on the drawings; a graphic scale is recommended.
  • Initial Survey. A site survey showing all existing conditions prepared by a NYS licensed Land Surveyor.
  • Title Sheet. Should clearly describe the project location, including the adjacent streets, properties, etc. and a graphical scale. Drawing notes should include building code occupancy classification, zoning use group, zoning analysis of bulk, building code construction classification, and other systems as applicable.
  • Drawing Index. A list that clearly identifies all the information that may be involved.
  • Site/Plot Plan. Clearly show the size and location of the lot, show all existing structures on the zoning lot, and include all dimensions of yards, building footprint, and other relevant information such as streets, adjacent buildings, curb cuts, north arrow, etc. The area of proposed work shall be clearly identified on the plot plan.
  • Floor Plans. Show existing and proposed conditions; clearly identify rooms’ names and use them consistently between the different discipline drawings. Coordinate between all trades / disciplines (architectural, structural, mechanical, plumbing, sprinkler and standpipe) to ensure that the proposed scope of work is complete and shown on all submitted discipline drawings. For example, where required, architectural drawings must indicate fire rating for partitions, ceiling, walls; location of penetrations through fire rated assemblies; and schedules for doors, windows and finishes materials.
  • Building Elevations. Required if the project involves the alteration, enlargement, reduction, renovation, repair or modification of the building exterior.
  • Building Sections. Required when the project involves an alteration, enlargement, reduction, renovation, or modification to the building, which includes cross and longitudinal sections of the all or part of the building.
  • Detail Drawings. These drawings contain significant information required to clearly communicate the scope of work, in a magnified form, such as structural connection details, wall type details, roofing details, etc.
  • Riser Diagrams. If the project involves alterations to existing or installation of new piping (oil/gas) combustion and ventilation ducts, riser diagram must show these details, including elevations across floors. See relevant Building Systems Guidelines (Mechanical, Plumbing, Sprinkler, and/or Standpipe) for more information.
  • Building System Schedules.  Schedule of equipment showing Make, Model, capacity, fuel type, heat input/output, efficiency, maximum pressure, GPM, RPM and electrical characteristic. See relevant Building Systems Guidelines (Mechanical, Plumbing, Sprinkler, and/or Standpipe) for more information.
  • Energy Analysis. If the project scope includes one of the following, than energy analysis is required on the plans, and can be provided on drawings in the form of Tabular Analysis, ComCheck/ResCheck, or by using a Code compliant energy modelling program.
    • Addition or replacement of exterior walls, roof, and/or floors
    • Additions or replacement of exterior vertical glazing, skylights, and/or doors
    • Addition or replacement of the above, if separating a conditioned space from an unconditioned space
    • Vestibules
    • Loading Docks
    • Interior Lighting
    • Addition or replacement of Heating and/or Cooling Systems
    • Addition or replacement of mechanical ducts
    • Addition or replacement of heating and/or cooling piping
    • Addition or replacement of heating systems > 600,000 BTU/h or cooling systems > 480,000 BTU/h, thereby triggering the NYCECC commissioning requirement in addition to other requirements.
    • Accessibility for persons with physical disabilities to comply with BC Chapter 11
    • Roofing and roof parapet walls with details
    • Lot Line windows replacement or new openings in accordance with permitted percentages
    • Interior elevations
    • All of the various building systems and equipment details*
    • Flood zone compliance
    • Light and Air calculations for habitable rooms in residential areas of mixed buildings**
    • Site Safety plans
    • Tenant / Occupant Protection Plan, if applicable
  • If applicable, additional elements required on drawings include:

*Refer to Project Guidelines for Building Systems installation and modification projects.
**Refer to Project Guidelines for Residential Alteration or Renovation projects.
Refer to Minimum Requirement for Review of Design Drawings available at the following link:

Submission of Construction Documents

The Registered Design Professional, who is the Applicant of Record, is responsible for a complete submission of construction drawings when filing with the Department, which includes the project application, drawings, and coordination of documents as summarized below.

  1. Application Intake. The online submission of project application shall occur by completing the intake form with key project information. Based on the project’s scope, the applicant may be required to complete the following sections:
  2. i. Project Work Details (former PW-1 Forms)

    ii. Special Inspections (may be required for subdivision of an existing buildings)

    iii. Remittance of Project Application Fees

  3. Drawings. The alteration project drawings should clearly reflect the scope of work and include all affected systems. Examples of this are as follows:

  4. Designator Sheet Number: Sheet Description
    T-001.00 Title Sheet, Site Plan, Drawing Index, General Notes, required special/ progress inspections list, and Legends
    A-100.00 Existing and Demolition Floor Plans
    A-101.00 Proposed Floor Plans
    A-200.00 Proposed Reflected Ceiling Plans
    A-300.00 Proposed Enlarged Floor Plans
    A-301.00 Proposed Interior Elevations and Details
    A-400.00 Existing and Proposed Façade Elevations
    A-401.00 Existing and Proposed Cross Sections
    S-100.00 Structural Plans and Details
    S-101.00 Structural Floor Plans and Details
    P-100.00 Floor Plans - Plumbing
    P-101.00 Plumbing Riser Diagram – Gas Riser Diagram - Piping
    P-102.00 Plumbing Fixture Schedules – Plumbing Details
    SP-100.00 Sprinkler Floor Plan
    SP-101.00 Sprinkler Riser Diagram and Details
    SD-100.00 Standpipe Floor Plan
    SD-101.00 Standpipe Riser Diagram and Details
    M-100.00 Mechanical System Equipment and Schedules
    M-101.00 Reflected Ceiling Plan for Mechanical System
    EN-100.00 Energy Code Analysis

    Drawing Legend to include: Symbols, abbreviations, notes and definition, and list all applicable Building Code section numbers

    Recommended Drawing Designators

    A: Architectural: Mandatory designation for drawings showing architectural work.
    S: Structural: Mandatory designation for drawings showing structural work.
    P: Plumbing: Mandatory designation for drawings showing Plumbing work including riser diagrams and plumbing details
    SP: Sprinkler: Mandatory designation for drawings showing sprinkler work including floor plans, riser diagram and sprinkler system details
    SD: Standpipe: Mandatory designation for drawings showing standpipe work including floor plans, riser diagram and standpipe system details
    M: Mechanical: Mandatory designation for plans showing mechanical work
    EN: Energy Analysis: Mandatory designation.

  1. Required Documents. Based on buildings location, designation, and the project’s scope of work, the following submissions may have to accompany the drawings at intake:
    • DEP – HCP/SCP forms, and MS4 – Municipal Separate Storm Sewer; for sanitary and/or storm water connections to street services
    • OER authorization - as required by ZR little E designation
    • FDNY – Notification or Letters of No Objection
    • Tenant/Occupant Protection Plan, if applicable
    • Mayor Office for People with Disabilities (MOPD)
    • Federal Emergency Management Agency Flood Insurance Rate Map – FIRMS
    • Transit Authority Approval
    • DOT Approval
    • Landmark approval
    • Public Design Commission Approval
    • NYC DPR – ST1 (Street Trees)
    • City Planning – approval or certification if required by ZR
    • BSA approval, if applicable
    • HPD approval - for inclusionary housing residential part of mixed use building, as required by ZR
    • DEC – if in coastal erosion hazard area or wetlands
    • SRO MD Anti-Harassment checklist – if applicable, for residential part of mixed building
    • HPD Certificate of No Harassment – if applicable, for residential part of mixed building
    • Loft Board (DOB) – approval required to submit loft conversion application to DOB – if applicable, for residential part of mixed use building
  1. Plan Review for Approval or Acceptance, and Audit.
    • Plan Review ─ Following submission of a complete set of construction documents, the application is assigned for review to a DOB Plan Examiner.
    • Professional Certification – Based on the owner’s consent, the Applicant of Record may professionally certify that a project’s design is in accordance with the NYC Code, Zoning Resolution, and all applicable Rules and Laws. See Buildings Bulletin 2016-010.
      • Zoning Check. Immediately after the permit issuance of a professionally certified application, DOB performs a Zoning Check to ensure general compliance with the Zoning Resolution and Code.
      • Audit. Professionally certified applications may also be subject to audit.
  1. Post Approval Amendments. Any changes to approved scope of work that are significant and substantive will require submission of revised documents and/or plans as a post-approval amendment (PAA). Approval of an amendment must be obtained before the work is completed. Changes that are not substantive do not require a PAA; however these changes must be shown on plans and included in the As-built submission at the end of the project (AC 28-104.3).
    • Vertical and Horizontal Enlargements - Any addition to the floor area
    • Conversions - An expansion of an occupancy classification or use group, or any similarly new use in an area not previously used for such purpose.
    • A reduction to an existing building’s floor area that impacts the Certificate of Occupancy.
    • Structural changes
    • Egress Modifications – Any change in the exiting width, length of travel distance, or exit way/exit door location(s), or occupancy load of exits, or any change in number of required exits in a building
    • Expand scope to add building systems, including any new equipment
    • Any addition or removal of plumbing, gas or mechanical risers
    • Any reduction below the minimum number of code required fixtures
    • Any changes to roof drains
    • Any alteration of gas appliances and other system components
    • Changes to scope of work that require additional Special or Progress Inspection(s).
  2. The following list, while not all inclusive, are examples of some of the substantive changes that must be submitted for review to amend the approved plans:

  1. As-Built Submission. All changes must be submitted in an ‘As-built’ drawing at the end of the project.

REFERENCE NOTE: Organizations like the AIA, CSI and National Institute of Building Sciences work jointly to create national standards for consistent documentation and data organization, to assist in communication and coordination across the design and construction industry.
(See for more information.)

Special and Progress Inspections

As per BC Chapter 17, alteration work may require certain Special and Progress Inspections to be performed during and at the end of construction as outlined in the table below. Prior to Approval, the Applicant of Record is required to identify all required Special and Progress Inspections (BC 1704.1). Prior to DOB permit issuance, the owner must typically engage a registered Special Inspection Agency (SIA) who will take responsibility for the Special and Progress Inspections. The applicant of Record may perform these inspections if they are also an SIA. Inspection discrepancies and hazardous conditions shall be reported to the super-intendment of construction, as well as to the site safety coordinator or site safety manager, for correction, per BB 2016-006 and 1 RCNY 101-06. Per BC 1704.1.2, the Contractor cannot hire the Special Inspector.

Based on the scope of work, an alteration project may be required to comply with the following Special and Progress Inspection requirements:

Structural Steel

May include steel welding, High Strength Bolting and Steel Details (BC 1704.3).

Concrete: Cast-In-Place and Precast

Required where the total concrete placement on a given project is more than 50 cubic yards or other conditions. Precast may be needed during façade renovation project (BC 1704.4). Also see BC 1905.6, BC 1905.3, BC 1913.5 and BC 1913.10.

Wood – Installation of Prefabricated I-Joists

Are subject to Special Inspections in accordance with Section 1704.2 and the requirements of Section BC 2303.1.2 (BC 1704.6.3).

Subgrade Inspection, Subsurface Conditions, Borings and Test Pits

Are subject to Special Inspections in accordance with Section BC 1704.7

Deep Foundation Elements

Are subject to Special Inspections in accordance with Section BC 1704.7.

Helical Piles

Are subject to Special Inspections in accordance with Section BC 1704.8.5.

Structural Stability – Existing Buildings

Alteration of existing structural systems or elements, such as columns, girders, beams, bearing walls, etc. where the stability or integrity of a structural system is to be temporarily diminished, in accordance with Sections 1704.20.6 through 1704.20.10.

Excavations – Sheeting, Shoring, Bracing and Underpinning

Methods employed to protect the sides of excavations shall be subject to Special Inspections in accordance with Sections BC 1704.20.2 through BC 1704.20.10 and BC 1814.

Fire-resistant Penetration and Joists

Special Inspections for penetration of fire-resistant elements and assemblies; and related fire-stops in accordance with Sections BC 1704.27.1 and BC 1704.27.2.

Flood Zone Compliance

Special Inspection for flood zone compliance shall be as required by BC Appendix G and BC 1704.29. Also BC 1704.5 if raising or moving a building for flood zone compliance and BC 110.3 to record lowest floor elevation


Load bearing masonry, glass unit masonry and masonry veneer shall be inspected and verified in accordance with the requirements of sections BC 1704.5.1 through BC 1704.5.3, depending on the structural occupancy category of the building or structure

Footings and Foundation

Footing and foundation inspections shall be made after excavations for footings are complete and any required reinforcing steel and required forms are in place as per BC 110.3.1.

Structural Wood Frame

Progress Inspections shall be performed for wood structural framing to determine compliance with the approved construction documents as per BC 110.3.3.

Fire-Resistance Rated Construction

Fire-resistance-rated partitions, floors, ceilings, shafts, and shutters as per BC 110.3.4.

Energy Code Compliance Inspections

Progress and Special Inspections

Other Progress and Special Inspections

Plumbing Systems, Fuel Gas, and Sprinkler Systems, Mechanical heating or cooling systems (including the seismic isolation of such piping and equipment per BC 1707), mechanical demolition, percolation tests for drywells and water detention systems, emergency & standby power systems, luminous egress paths.  See other Review Manuals/Guidelines for such Systems projects.

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