Design Professional Requirements:
Loft Law IMD (Alteration)

Applicability of Code and Zoning

An Interim Multiple Dwelling (IMD) Legalization is an alteration project. Mainly, Multiple Dwelling Law Articles 7-B and 7-C, in particular MDL Section 277, are used to ensure statutory compliance.

In addition, portions of the current 2022 NYC Construction Codes (Administrative, Building, Plumbing, Fuel Gas and Mechanical Codes) or Prior Codes, such as the 1968 Code and a few provisions in the 1938 Code, depending on the Code under which the building was constructed, may also be required. Note that issues covered under the fourteen exceptions in AC 28-101.4.3 must comply with 2022 NYC Construction Code, unless otherwise grandfathered by de facto status to use Prior Code; but any other issues, must establish compliance with MDL §277.

The following table is a brief overview of building Code compliance path for buildings built prior to 1968:

MDL §277

1938 Code

1968 Code

2022 Code

  • Size of Mezzanine
  • Min habitable room sizes
  • Distance to window to provide natural light and air
  • Egress
  • Exterior wall fire rating
  • Sprinkler coverage
  • Building limitations
  • Shaft enclosure
  • Vestibule
  • Kitchen and kitchenette
  • Skylight
  • Construction Classification
  • Egress of non-residential portion of the building

  • Natural light and air
  • Alcove
  • Skylight
  • Mezzanine egress
  • Travel distance
  • Accessibility (second window period)
  • Fire escape
  • Sprinkler coverage (second window period)
  • Occupancy Classification
  • Occupiable rooms
  • Fuel gas, Plumbing, Mechanical
  • Fire Protection System performance standard
  • Elevator – alteration and addition
  • Construction safety
  • Encroachment
  • Special Inspection
  • Materials and finishes
  • Security grilles
  • Energy Efficiency (2020 ECC)
  • Roofing
  • Handrails and guards
  • Flood
  • Structural
  • Generator
  • Parking
  • Mold protection

As required to legalize the de facto IMD, related new alteration work must comply also with the 2020 New York City Energy Conservation Code (NYCECC), the 2011 NYC Electrical Code and applicable Local Laws, Rules and regulations.

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 Department of Environmental Protection (DEP), NYC Department of Transportation (DOT), NYS Department of Environmental Conservation (DEC), NYC Landmarks Preservation Commission (LPC), NYC Department of Parks and Recreation (DPR), and others.

NOTE: The following is a list of key zoning, Code and other regulations that may be relevant in the project’s design; it does not cover all applicable regulations.
The numbering of the MDL provisions in table below (MD 1 through MD 9) is to structure them for ease of reference within the guide.

MDL Provisions

IMD legalization projects require compliance with the Multiple Dwelling Law (MDL) Article 7-B JOINT LIVING-WORK QUARTERS FOR ARTISTS, OR GENERAL RESIDENTIAL OCCUPANCY OF LOFT, COMMERCIAL OR MANUFACTURING BUILDINGS, and other referenced sections of the Multiple Dwelling Law as follows:

IMD (MDL) Element Components

MDL Regulations


MD 1 - Use and Occupancy

MD 1.1

Joint living-work quarters for Artists (JLWQA)

  • IMDs - used as JLWQAs (overview) but only in Districts M1-5A and M1-5B
  • MDL Classification
  • Zoning UG
  • BC Occupancy Classification

§281§275 & §276

ZR 42-14: UG 17D
PW-1 form (instructions);
2022 BC 310: R-2

MD 1.2

General Residential Use

  • IMD - general residential use (overview)
  • MDL Classification
  • Zoning UG
  • BC Occupancy Classification

§275§277, and §281

PW-1 instructions,
ZR 22-12: UG 2,
2022 BC 310: R-2

MD 1.3

Manufacturing or Commercial Use within same building as IMD(s)

  • Zoning UG
  • BC Occupancy Classification

§277.3 & §277.4;
§278 with reference to §61 and exceptions; §281.5

TPPN 9/93 - item 11ZR 42-00 or ZR 32-00 (compliant); ZR 52-00 (lawful non-compliant)
2022 Code: Occupancy Classification per BC Chapter 3

MD 2 – Exterior: Yards, Courts & Distance between Buildings

MD 2.1

Yards and courts

§277.6(a) - apply §212 as if for OLT

Also see Zoning Below

MD 3 - Interior

MD 3.1

Minimum IMD and Room Sizes: Ceiling Heights & Areas

MD 3.1.1

Enlargements – Generally Not Allowed

§286.2(i) and §277.7(d)

MD 3.2

Legalization –
Interior Mezzanines (Interior Balconies)

§277.6(b) references 1968 C26-1205.1 through 1205.6 and C26 1205.7 (AC 27-745 – 749 and 27-751);

1968 AC 27-232 (Occupiable Room), referenced in 1968 C26-1205.12022 BC 1205.2.41968 C26-1202.2 (AC 27-733)TPPN 9/93 - item 8;
ZR 43-17

MD 3.3

Legalization –
Minimum IMD and Room Sizes, Lighting and Ventilation

MD 3.3.1

Openings / Windows for natural lighting and ventilation:

  • IMD
  • Other Residential: Lofts, Manufacturing & Commercial
  • Cooking & Eating Spaces: Kitchens & Kitchenettes 
  • Open and enclosed stairways, fire-stairs, elevators and other similar shafts
  • Bathrooms and Toilet Rooms

§277.6(b) references 1968 C26-1205.0 through C26- C26-1205.7§277.7§277.10

2022 BC 1208.2 (for clarification); 2022 MCHMC 27- 2057; Also see Zoning Requirements below


Artificial Light

§278, which references §37

MD 3.3.2

Minimum Size - IMD & JLWQA Units, and Rooms:

  • JLWQA & IMD units
  • Habitable & Occupiable Rooms
  • Alcoves & Interior Rooms

MDL §277.6(b) – JLWQA / IMD
MDL §277.7(a) – JLWQA
MDL §277.7(b) - IMD
MDL §281.5 – IMD
MDL §278 & 31.6 - Rooms

1968 C26-1205.0 through 1205.7
2022 BC 1208.2
 TPPN 9/93 (7) – alcoves
Also See Zoning Requirements Below

MD 3.4


§278, which references §60

Also see zoning below

MD 4 – Egress

MD 4.1

Exit Components – Quantity, Construction  & Options

MD 4.1.1

Non-fireproof MD Building Egress Options:

  • One stair and fire escape; or
  • One stair, enclosed hallway, and wet sprinkler in entire building; or
  • Two stairs, and enclosed hallway having sprinklers




MD 4.1.2

Fireproof IMD Egress Options:

  • Two stairways and enclosed sprinklered hallway; or
  • One interior stairway, one screened exterior stair designed in accordance with Labor Law, and enclosed hallway; or
  • Comply with any of the options for a non-fireproof building; or
  • Comply to requirements for Fireproof Hereafter Erected multiple dwelling

§277.9(b)(i); or

§277.9(b)(ii); or

§277.9(b)(iii) references §277.9(a)(i), (ii) or (iii); or
§277.9(b)(iv) references  MDL §102

Labor Law §268 - Exterior Screened Stairway

MD 4.2

Intervening Hallway

  • Fireproof and Non-fireproof Buildings

§277.9(c), §277.9(d);
or option §277.9(a)(iii)

MD 4.3

Entrance Hall / Lobby

§277.6(a) references §189.3

MD 4.4

Exit Stairway

MD 4.4.1

Stairway Width

§277.6(a) refers to MDL §189.3;
Fireproof Building - §277.9(a)(iv) refers to §102.2

MD 4.4.2

Stairway enclosure


MD 4.4.3

Bulkheads / scuttles

§278 refers to §62.1

MD 4.4.4

Stairway ventilation


MD 4.5


§278 in references §53; §278 references §62.2; §277.9(a)(i) & §277.9(b)(iii)

1 RCNY 15-10

MD 4.6

Travel distance


AC 27-360

MD 4.7

Mezzanine egress

§277.9(i) and §277.9(f)

AC 27-360(c)
AC 27-375(l)

MD 4.8

Stair materials

  • Typically non-combustible Construction
  • Wooden stairs
  • Stair Removal, and Handrails, posts and guardrails

§277.6(a) references §189

AC 101.4.3, Exception 13


MD 6 - Categories of Construction Class & Fire Resistance Rating

MD 6.1

Categories of Construction/Construction Classification

MD 6.1.1

Options: Fireproof/Fire-protected



§277.2(a); §101




1938 Code - Class 2 Construction

MD 6.1.2

Options: Non-fireproof

§277.2(b); §4

1938 C26-241.0 or 244.0;
1968 section §C26-504.2 (AC27-340);
AC 27-123.2

MD 6.1.3

Building Construction Elements


1968 AC 27 Table 3-4:  J-2 Occupancy Group

MD 6.1.4

Frame Construction

§278, which references §56

MD 6.2

Exterior Envelope – Fire Resistance

MD 6.2.1


  • Incombustible is Non-combustible
  • Materials


1968 AC 27-232
2022 AC 28-101.4.3, Exception 92022 BC Chapter 7

MD 6.2.2

Exterior walls less than 30’-0” away from another structure

§277.1(a); §277.2(c)

1968 AC 27 Table 3-4

MD 6.2.3

Exterior walls more than 30’-0” (perpendicular distance) away from another structure

§277.2(a), (b) or (c)

1968 AC 27 Table 3-4

MD 6.2.4

Window Openings

  • Exterior Walls Windows
  • Windows opening onto Fire Escapes

§277.1(b); §277.8

1968 AC 27 Table 3-4

MD 6.3

Vertical and Horizontal Circulation - Egress Enclosures

MD 6.3.1

Egress Hallways & Corridors – Fire Rating

  • Apartment Entrance Doors

§277.9(d); §4.26, §101.3(d)§277.6(a) refers to §189; 277.8

MD 6.3.2

Stairway Construction

§277.9(e); §277.6(a) refers to §189


Additional Stairway requirements and Cellar stairs

§277.6(a) refers to §190

MD 6.4

Shaft Enclosures

  • Shaft fire-rating (MEP)
  • Elevator Shafts


1968 AC 27-344

MD 6.5

Roof Extension (Mezzanine Penthouse)

§277.6(a) refers to §186

MD 6.6

Fire Separation Between Tenancies - Vertical


MD 6.7

Fire Separation Between IMD and Manufacturing or Commercial Use

§281.5 & 29 RCNY 2-08 restrict many manufacturing uses;  §277.3;  §278 with reference to §61

MDL §277.3 refers to BSA rules & NYS Labor Law; TPPN 9/93 (Item 11)

MD 6.8

Cellar ceilings

§277.6(a) refers to §185

1968 AC 27 Table 3-4

MD 6.9

Wainscoting (optional)

§277.6(a) refers to §191 and §278 refers to §55.2

2022 BC for various materials

MD 6.10

Interior iron columns - fire protection


2022 BC 704 and 721BC Appendix Q

MD 7 - Fire-Protection: Smoke Detectors and Sprinkler Systems

MD 7.1

Where Sprinkler Systems are Required within Building having IMDs: Based on Construction Class, Exterior Envelope, Building Structural Elements, and Egress

§277; See MD 3, MD 4, and MD 6 above

See Code Requirements Table below.

MD 7.2

IMD unit - Sprinkler System Requirements

See Code Requirements Table below.

MD 7.3

Manufacturing and Commercial Occupancies within Building having IMDs:

  • Sprinkler systems within such commercial occupancies
  • Sprinkler Systems in Hallways and Stairways when shared with IMDs


See Code Requirements Table below.

MD 7.4

Smoke and Carbon Monoxide Detectors and Alarms

MDL §277.7(g)

BC 907 & 915.1; Also see Code Requirements Table below.

MD 8 – Sanitation & Health

MD 8.1

Plumbing & Space Heating:

  • Water supply
  • Bathrooms
  • Sanitary & Storm Drainage
  • Space Heating

§277.13; §75
§277.13; §76
§277.13; §77
§277.13; §79

2022 PC Chapters 4, 5, 6, and 7HMC 27-2063

2022 MC

MD 9 - Waiver

MD 9.1

Waiver of MDL 277 Requirements for IMDs


AC 28-103.3, New York City Charter 645(b)

Discussion of MDL (IMD) Provisions

The following items discuss the MDL Design Professional Requirements for IMDs, as listed in the table of review standards in previous section. Details are provided that are specific for each item listed in the above table. These guidelines outline key elements critical to understanding the MDL design professional requirements.

IMD (MDL) Design Elements: IMD alteration projects include a change in occupancy or use, which may trigger other requirements or changes related to egress, and light and air, all of which are detailed in the MDL.

MD 1 - Use and Occupancy

MD 1.1 - Joint Living/Work Quarters for Artists (JLWQA)

  • MDL Classification is assigned as CAA (Commercial Altered Class A); additional information is in DOB PW-1 form instructions.
  • The building must be located in the zoning district where UG 17D is a permitted use as-of-right, such as M1-5A and M1-5B.
  • Zoning Use Group (17D) must be selected.
  • JLWQA is not residential use, so the limitations on Home Occupation in ZR 12-10 are not applicable.
  • 2022 Construction Code Occupancy Classification must be selected as R-2, which may mandate various Code-related requirements.

MD1.2 - General Residential Use

  • IMD status is determined by the Loft Board. Once declared an IMD, MDL §275 and §281 allow such general residential use, regardless of zoning district
  • MDL Classification is assigned CAA (Commercial Altered Class A); additional information is in DOB PW1 User Guide instructions.
  • Zoning Use Group (UG 2) must be selected.
  • 2022 Construction Code Occupancy Classification must be selected as R-2, which may mandate various code related requirements.

MD 1.3 –Manufacturing Facility or Commercial Use in same Building as IMDs

  • Provided the Zoning Resolution allows manufacturing and commercial use groups (UG) in the building’s zoning districts, such uses may remain in the same building with the new IMDs / proposed dwelling units.
  • Please note: When forming an IMD at Loft Board, MDL §281.5 and 29 RCNY 2-08 restrict many manufacturing uses (UG 16, 17 and 18) from being within the same building as the proposed IMD.
  • The Zoning Resolution’s Use Group (UG) and 2022 Construction Code Occupancy Classification must also be selected for such commercial or manufacturing space. Any changes to such commercial or manufacturing spaces must be compliant with the relevant provisions in the Zoning Resolution, Code and MDL.

MD 2 – Exterior: Yards, Courts and Distance between Buildings

MD 2.1 Yards & Courts

Per MDL §277.6(a), any MDL §212 subdivision section provisions pertaining to Old Law Tenements (OLT) are applied to the sizing of yards and courts of buildings having IMDs. MDL §212.1 refers to MDL §26 for proposed yard and court dimensions. Because MDL §26.1(b) permits the use of local zoning ordinance to determine yard and court dimensions, and lawful existing non-complying yards and courts are permitted under ZR 54-00, all lawful existing yards and courts in IMD buildings shall be considered as in compliance. Also reference MD 3.3.1 (MDL §277.7(b)(ii) for minimum acceptable rear yard size with respect to habitable room windows facing rear yards.)

MD 3 - Interior

MD 3.1 Minimum IMD and Room Sizes: Ceiling Heights & Areas

MD 3.1.1 Enlargements - Generally Not Allowed

  • To ensure continued occupancy of IMD tenants per MDL §286.2(i) and ensure protection of tenants against any adverse living conditions created by construction, MDL §277.7(d) does not allow any IMD building, IMD unit, or any non-residential portion of a building also having an IMD, to undergo an interior or exterior enlargement unless the underlying zoning district permits such an enlargement, MDL §26 is applied, and such a change is separately approved by the Loft Board (certification w/ stamp on drawings and/or letter). Similarly, the Loft Board must separately approve any net reductions in size of an IMD building, IMD unit(s) or a non-residential portion of a building with an IMD.

MD 3.2 Legalization - Interior Mezzanines/Interior Balconies of IMD

  • Sizes - Habitable Spaces (Sleeping and Living Spaces), associated with mezzanine or interior balcony, and penthouse mezzanine open to below §277.7(d) – Allowed if:
  • Maximum 33% area of room, using the method specified in BC 505.2, minimum 8’ clear height above & below habitable spaces, similar to BC 1208.2
  • Could have 7’ height min mezzanine related spaces as habitable space if also open to larger adjacent room with minimum of 80 sf, per 1968 C26-1205.7. However, this cannot be applied to an Open to Below mezzanine/penthouse arrangement
  • Sizes - Occupiable Spaces (office & storage, associated with mezzanine or interior balcony, & penthouse mezzanine open to below)
  • Office - 1968 AC 27-232 defines Occupiable Room, which is discussed in 1968 C26-1205.1. Such space is not the same as the MDL defined living room. Therefore, an office located in or below a mezzanine may be considered an occupiable room and acceptable as an MDL mezzanine, if a 7’ clear height minimum is provided per MDL §277.7(d). In addition, 7’ minimum clear height allowed for non-habitable spaces per current BC 1208.2, exception 4.
  • Storage- TPPN 9/93, item 8, if JLWQA or other type of IMD - If less than 7’, but more than 5’ of clear height below and if counted as floor area, can be storage ONLY, regardless of size of larger adjacent room. Such storage area can only be accessed by a ladder, as required. 

NOTE: ZR 43-17, if IMD is UG 17D, mezzanine requirements are similar to above.

MD 3.3 – Legalization - Minimum IMD Size, Minimum Room Size, Lighting and Ventilation; MD 3.3.1 – Openings/ Windows for Natural Light and Ventilation, and Mechanical Ventilation

1968 Subchapter 12 Provisions Referred by MDL §277



Other Residential

Occupiable rooms

1968 AC 27-745 as referred by MDL §277.6(b)

Habitable rooms

1968 AC 27-746 as referred by MDL §277.6(b)


1968 AC 27-747 as referred by MDL §277.6(b)


1968 AC 27-748 as referred by MDL §277.6(b)

Natural ventilation sources, including kitchen

1968 AC 27-749 as referred by MDL §277.6(b), and MDL §277.7(e)
NOTE: AC 27-749 permits skylight to be natural ventilation sources.

Area of ventilating openings (excluding kitchen)

1968 AC 27-750 as referred by MDL §277.7(a)(ii)


Area of ventilating openings for kitchen

1968 AC 27-750 as referenced by MDL §277.7(e)

Area of ventilating openings for kitchenette

1968 AC 27-750 as referenced by MDL §277.7(e)(i)
NOTE: MDL §277.7(e)(i) permits skylight to be used as kitchenette natural ventilation.

Minimum dimension of habitable rooms

1968 AC 27-751 as referred by MDL §277.6(b)

Mechanical ventilation of occupiable rooms

NYC Admin Code as referred by MDL §277.7(c)

IMD (General)

JLWQA (only)

Other IMD Residential

  • Lofts, Manufacturing & Commercial –
  • MDL §277.7(b)(i)requires one or more windows in such IMD unit to open upon a street, court, yard, or open area having areas and dimensions as indicated in this MDL section. If open area involves a building on an adjoining zoning or tax lot, an easement and/or restrictive declaration will also be required. (NOTE: One of the options in MDL §277(b)(i)(A) through (D) are required; in addition, the 5’ minimum dimension to the rear yard line, per MDL §277(b)(i)(E), must always be applied) See diagrams below:

Image 1

Image 2

Image 3

Image 4

  • MDL §277.7(b)(ii)provides specific sizes for every window in a living room in such IMD unit and the minimum outside area that such windows may open upon, with respect to the rear lot line

Cooking & Eating Spaces:  Kitchens and Kitchenettes

Per §277.7(e), the following are required for Kitchenettes

  • A kitchenette has a floor area less than 80 sf
  • As an option, per 1968 AC 27-749 and 27-750, a kitchenette could have natural ventilation provided by windows, skylights, doors, louvers, etc., or supplementary outside air provide by mechanical means, in addition to some natural ventilation openings, is also possible
  • As another option, windows or skylights can be used to provide such natural light and air, but must be located & designed as detailed in MDL §277.7(e)(i)
  • As a final option, a kitchenette could be provided with mechanical exhaust & ventilation as detailed in MDL §277.7(e)(ii)

Open and enclosed stairways, fire-stairs, elevators and other similar shafts

  • Metal skylights required with screens, of certain area and construction as discussed in MDL §277.10(a)
  • Opening for ventilation required at top per MDL §277.10(b)or ventilated per applicable Code

Bathrooms and Toilet Rooms

MD Artificial Light

Every public halls, stairway, vestibule, entranceway, or fire stairs and towers must have a minimal illumination level in accordance with MDL §278, which references MDL §37. Alternatively, and for other areas not mentioned in this MDL §37, the applicable code can be used.

MD 3.3.2 – Minimum Sizes of IMD unit, JLWQA unit and Rooms

Minimum size of JLWQA unit, or other IMD unit

Minimum Size of Rooms (General):

  • Habitable Rooms

Per AC 1968 C26-1205.7, typically minimum clear room width of 8 feet in any part, minimum clear area of 80 square feet, and minimum clear ceiling height of 8 feet, but reductions in area and clear width are possible under certain conditions, per parts (a), (b), (c) & (d) of this same code section. Note that foyers and dining spaces within the limitations set forth in BC 1208.2 are not habitable rooms, but larger than such limitation shall be considered as habitable rooms and shall be provided with natural ventilation.

  • Occupiable Room

Per BC 1208.2, occupiable rooms, such as a non-mezzanine type office, can have a ceiling height that is not less than 7’-6”, but storage rooms and laundry rooms may have a 7’ height clearance from floor to ceiling. Compliance with MDL §278 requirements, which refers to MDL §31.6 can be done with respect to 60 sf min, 6’ min width and no more than 1 person if under 75 sf. Such occupiable rooms may be classified as Home Occupation, subject to ZR restrictions, see Zoning discussions.

Alcoves & Interior Rooms

  • An alcove can be treated as a living room / habitable area by providing opening to a larger room having dimensions and windows as required by MDL & code for a living room for light and ventilation. Per TPPN 9/93 (7), to have a legal alcove, an opening in an alcove wall should be directly across and facing (parallel to) ventilating windows that have an area that is at least 10% of the combined floor area of the rooms. Such alcove wall opening must be at least 8’-0” in width and the bottom sill of such opening should not exceed a height of 40%, measured from the floor to ceiling level. A door may also be part of such alcove wall.
  • Multiple alcoves are allowed as long as compliant with above.
  • If such alcoves or interior rooms do not meet the above requirements, they may still be treated as occupiable rooms, if all general requirements for occupiable rooms are provided, as previously described above.

MD 3.4 – Parking

§278 refers to MDL §60(Motor vehicle storage). If new parking is provided, it must comply with MDL §60 and BC 406.

MD 4 - Egress

MD 4.1 Exits – Quantity/Options

MD 4.1.1 - Egress in Non-Fireproof IMD Buildings
Applicant shall choose one of the three options (i), (ii) or (iii) of §277.9(a) to determine the required quantity of exit stairways, fire escapes and the need for sprinklers and/or an enclosed hallway/corridor. Note that per §277.9(a)(ii) indicates a building height limitation of 75 ft. and a floor area limit of 5000 sf on each floor.

MD 4.1.2 Egress in Fireproof Buildings

Applicant shall choose one of the four options in §277.9(b) to design number of required stairs.

  • Option §277.9(b)(iii)allows compliance with §277.9(a) for a non-fireproof or fire-proof building with a building height limitation of 75 ft or 7 stories; or
  • If the egress option in §277.9(b)(ii)is chosen, Labor Law §268 & §262 requirements must be adhered to, which include, but are not limited to screen material of exterior stairway, riser height and depth, access balconies, fireproof building windows opening upon such stairways, & discharge from such stairways; or
  • Compliance with §102 for Fireproof Hereafter Erected multiple dwelling

MD 4.2 Intervening Hallway

  • Per §277.9(c) and (d), when there are three or more dwelling units on the floor, a minimum 1-hour fire-resistance rated intervening hallway is required between each dwelling unit door and exit stairway door.
  • If Egress Option described for a non-fireproof building, §277.9(a)(iii), is chosen, a 1-hour fire-resistance rated and sprinklered intervening hallway is required when two or more dwelling units are on a floor.

MD 4.3 Entrance Hall / Lobby

  • Every entrance hall or lobby shall have a minimum of 2’-8” of clear width, per MDL §189.3 as referenced by MDL §277.6(a). Also refer to Accessibility requirements in Code Section below, as required.

MD 4.4 Exit Stairway

MD 4.4.1 Stairway Minimum Width

MD 4.4.2 Stairway Enclosure Requirements

MD 4.4.3 Bulkheads/Scuttles

MD 4.4.3 Bulkheads / Scuttles

  • Per MDL §277.9(e), buildings with 4 stories and higher must provide stair bulkhead, otherwise a scuttle is required, but both are exempted if roof pitch exceeds 15 degrees.
  • Per MDL §278, a minimum 3’-6” high parapet or guardrail is conditionally required by MDL §62.1 where a bulkhead door or scuttle cover is within 4 ft. of the existing roof edge.

MD 4.4.4 Stairway Ventilation

Within stairways, buildings exceeding two stories shall be provided with either ventilation by a vented skylight or by a fixed louvered window as described in §277.10.

  • Skylight – If skylight is used, it shall be min 20 sf open area, having wire screen over and under glazing. Ventilator within skylight shall have a 1 sf min open area.
  • Window - If window is used, it shall be a minimum of 20 sf and have an integrated or adjacent fixed louver with a minimum open area of 1 sf.

MD 4.5 Fire Escapes

  • If egress option of §277.9(a)(i)or §277.9(b)(iii) is elected, such that fire escape is the second means of egress, it shall be constructed per §53, as referenced by §278.
  • Additional Requirements in 1 RCNY 15-10.
  • Radio and television antennas, and any other wiring cannot be attached to fire escape per §62.2, as referenced by §278.

MD 4.6 Travel Distance

§277.9(f) refers to the Administrative Code which is the 1968 Code, as referenced elsewhere in MDL §277.
Based on 1968 AC 27-360, travel distance is measured as follows:

  • Within dwelling unit: As measured from habitable room door to apartment entry door – maximum distance of 50 feet is allowed in a fireproof building, and a maximum of 40 feet is allowed in non-fireproof buildings.
  • On each floor:  As measured from the most remote point of the floor, which could be within an apartment, to the required vertical egress stair, horizontal exit passageway, or building exterior - maximum distance of 150 feet is allowed if the floor is unsprinklered, or 200 feet if the floor is sprinklered.

Alternatively, AC 28-101.4.4 permits elective compliance of 2022 BC provided that the applicant submitting a comparative analysis acceptable to DOB of the relevant fire safety and structural safety provisions under the 1968 Building Code and 2022 Building Code, and must demonstrate that by using the 2022 Code provisions, there is no reduction to the fire and life safety of the building.

MD 4.7 Mezzanine Egress

§277.9(f)refers to the “Administrative Code” which is the 1968 Code, as referenced elsewhere in MDL §2771968 AC 27-360(c)mandates that the egress path be measured along the inclined straight line through the center of the apartment’s mezzanine stair.

§277.9(i)requires the following for a mezzanine within an apartment:

  • Minimum 30” wide stair serving mezzanine, constructed of noncombustible materials. Bottom of such stair shall be within 20 feet of the apartment’s exit door or fire escape.
  • A spiral stair is permitted if constructed in accordance with 1968 AC 27-375(l)
  • Every portion of the mezzanine shall be within 50 feet of the apartment’s exit door or fire escape.

Alternatively, AC 28-101.4.4 permits elective compliance of 2022 BC provided that the applicant submitting a comparative analysis acceptable to DOB of the relevant fire safety and structural safety provisions under the 1968 Building Code and 2022 Building Code, and must demonstrate that by using the 2022 Code provisions, there is no reduction to the fire and life safety of the building.

MD 4.8 Stair Materials

  • Stairs shall generally be noncombustible §189.1, as referenced by §277.6(a).
  • However, per §277.9(g), an existing wooden stair is permitted to remain provided stair enclosure is sprinklered and stair and landing soffits are fire retarded.
  • If an entire stair is replaced, 2022 BC must be followed for replacement of handrails in accordance with AC 28-101.4.3, Exception 13. Such new stair must have appropriate step treads, riser heights, and non-slip surfaces per appropriate prior code, or per current code.

MD 6 - Categories of Construction & Fire Resistance Rating

MD 6.1 Categories of Construction

Construction Class - PW1 form should indicate appropriate building construction class, based on earliest code version for which the building complies, such as the 1938, 1968 Code, etc. At the option of an owner, job could be filed under current code, and examiner will examine as such.

MD 6.1.1 - §277.2(a) requires that fireproof buildings be constructed in accordance with either of the following:

MD §277.2(a) – Fireproof per the requirements set forth in MDL §101 Requirements for fireproof construction; or

MD §277.2(a) – Fireproof can also be constructed in accordance with Construction class two (of the 1938 AC 26).

Max # of Stories4

Height4 - ground to ceiling of top floor

Building Depth

Fully wet sprinklered (FWS)/not fully sprinklered (NS)3

Standpipe system required

Maximum floor area between 2hr rated partitions2

1hr. Rated Ceilings






3,000 SF







3,000 SF







5,000 SF







5,000 SF







10,000 SF


1 MDL defined “non-fireproof” construction, but also having a minimum 2-hour rating, as an option, could match with 1938 Code Class 3- non-fireproof in C26-241.0, or Class 6-Heavy Timber in C26-244.0.
2 Partitions constructed in accordance with 1968 AC §C26-504.2 (AC 27-340) Fire Divisions.
3 Also comply with additional sprinkler requirements per AC 27-123.2 (AKA LL 10/99) based on IMD window period, see code discussion.
4 Use MDL §4 definitions of story, cellar and basement to determine the building height, discussed throughout MDL §277

MD 6.1.3 Building Construction Elements

Per MDL §277.2(c), building’s construction elements can comply with 1968 AC 27 Table 3-4 for a J-2 Occupancy Group.

MD 6.1.4 Wood Frame Buildings / Extensions –

MDL §278 refers to the MDL Section 56MDL §56 mostly prohibits wood frame buildings, and frame extensions, from being converted to a dwelling.

MD 6.2 Exterior Envelope - Fire Resistance

MD 6.2.1 General

MD 6.2.2 Exterior walls less than 30’-0” away from another structure

  • §277.1(a) requires exterior walls of  all buildings less than 30’-0” (perpendicular distance) away from another structure to be:
  • Non-combustible and 3 hour fire-resistive rated including all columns and beams; and
  • If exposed non-rated columns or beams are also present and building is non-fireproof, the exterior wall shall also be sprinklered per 277.1(a); or
  • Fire rate in accordance with 277.2(c), i.e. the 1968 AC 27 Table 3-4, in lieu of (i) and (ii) above.

MD 6.2.3 Exterior walls more than 30’-0” away from another structure

  • MDL §277.2(a)requires exterior walls of all buildings more than 30’-0” (perpendicular distance) away from another structure.
  • Such walls to be constructed in accordance with §277.2 (a), (b) or (c).
  • An additional sprinkler system, in accordance with §277.1(a) is required on the interior of non-fireproof buildings having unrated structural columns and beams along exterior walls.

MD 6.2.4 Window Openings:

  • Exterior Wall Window Openings MDL §277.1(b) references the 1968 Code. Therefore, the percentage of window openings allowed in an exterior wall shall be:
  • In accordance with 1968 AC 27 Table 3-4; or
  • Per MDL §277.1(b), fire protected and provided with either a minimum of one sprinkler head per window, or an automatic window closing device
  • Windows opening onto Fire Escapes – MDL §277.8 allows exterior wall windows that open onto fire escapes to be provided with wire glass, unless such windows are protected by a wet pipe sprinkler head, having a minimum of one head per window.

MD 6.3 Vertical and Horizontal Circulation - Egress Enclosures

Also See MD 4 for Egress

MD 6.3.1 Hallway & Corridor Enclosures

§277.8and §277.9 (d)require enclosed public hallways to be 1-hour fire rated. The doors to such hallways shall be self-closing and made of fireproof construction, as defined in the MDL §4.26, i.e. have 1-hour fire-rating per MDL §101.3(d)MDL §277.6(a) refers to MDL §189, which contains more requirements for protection of public halls.

  • Apartment Entrance Doors -Per §277.8, apartment doors opening into hallways and corridors shall be self-closing and fireproof / fire-rated to match the minimum 1-hour fire-rated hallway requirement
  • MD 6.3.2 Stairway Construction– MDL §277.9(e) has the following requirements for public stairway fire rated enclosure fire rating and sprinklers:

Stairway Enclosure:  Minimum Fire rating

Category of Building Construction

Maximum # of stories

Sprinkler in Stairway

Sprinkler Throughout Building

1 hr.



Not Required


1 hr.





1 hr.





2 hrs.



Not Required


*Sprinkler system might still be required in building based other MDL §277 provisions, or if required by AC 27-123.2 (AKA LL 10/99), based on IMD window period, see discussion in Code.

MDL §277.6(a) refers to MDL §189 and §190, which contain additional requirements for protection of public stairways, such as cellar stair construction & self-closing doors.

MD 6.4 Shaft Enclosures

  • In general, all shafts containing mechanical, electrical and plumbing riser, shall have the following enclosure requirements per §277.11:
    • Be enclosed with incombustible material of two-hour fire rating; and
    • Comply with the 1968 AC 27-344requirements; or 
    • If existing shaft enclosure is currently constructed, in part, of combustible material, such shaft may remain of such partial combustible construction, but be upgraded to obtain a two-hour fire rating.
  • Elevator shafts fire protection requirements, per §277.15, are as follows:

    Shaft Enclosures must be
    1. Provided with fire-rated self-closing doors; or
    2. Have a vestibule in front of it with non-combustible 2-hour fire resistance rated walls and self-closing fire-rated & fire-stopped doors;
    3. A 2-hour fire resistance rated noncombustible material; or
    4. If existing shaft enclosure is currently constructed, in part, of combustible material, such shaft may remain of such partial combustible construction, but be upgraded to obtain a two-hour fire rating;

Elevator Shaftway Doors

Doors shall be appropriately fire resistance rated; and

MD 6.5 Roof Extension - §277.6(a) refers to §186, which requires the roof of any MDL allowed extension (bulkhead, or as allowed by §277.7(d), an added penthouse mezzanine), to be:

  • Fire-retarded; or
  • Sprinklered

MD 6.6 Fire Separation Between Tenancies - §277.5 requires a minimum vertical fire-separation of 1-hour fire-resistance rating between tenants within a building.

MD 6.7 Fire Separation Between IMD and Manufacturing or Commercial Use - When forming an IMD at Loft Board, MDL §281.5 and 29 RCNY 2-08 restrict many manufacturing uses (UG 16, 17 and 18) from being within the same building as the IMD unit. Fire retarded ceilings between commercial/manufacturing and residential uses are required in accordance with MDL §278 with reference to §61, and TPPN 9/93, item 11.

MD 6.8 Cellar Ceilings - §277.6(a) refers to §185, which identifies fire-resistance rating / fire-retarding requirements for ceilings of either cellars or the lowest story of a building with no cellar. Alternatively, 1968 AC 27 Table 3-4 can be used.

MD 6.9 Wainscoting - §277.6(a) and §278, which refer to §191 and §55.2 respectively, have fireproofing & fire-stopping requirements with respect to preserving the fire-resistance rating of walls in corridors, hallways, stairways and apartments. Any materials used must also comply with 2022 BC, for example, fire retardant treated wood used for wainscoting must comply with 2022 BC 2303.2.

MD 6.10 Interior iron columns - fire protection

In accordance with §277.14

  • Interior iron columns in unsprinklered buildings, whether located within a fireproof or non-fireproof building, shall be enclosed in 3-hour fire-resistive rated material. Such enclosures shall be UL listed or comply with prescriptive requirements in BC 704and BC 721; or
  • However, in non-fireproof buildings, interior iron columns may be left exposed, if the following is also done:
  • Sprinklers are provided every 4 feet, on all types of exposed or unrated beams and columns at the exterior wall in accordance with 277.1(a); and
  • Interior iron columns, are protected by two sprinkler heads located a minimum 18” away from each other, but no further than 4’-0” on center, and on opposite sides of each such column; or

The building is fully sprinklered in accordance with BC Appendix Q requirements, and the exterior wall unrated beams and columns are still provided with sprinkler protection in accordance with §277.1(a)

MD 7 - Fire-Protection: Sprinkler System

MD 7.1 Where Sprinkler Systems are Required within buildings having IMDs, based on Construction Class, Exterior Envelope, and Building Structural Elements

  • §277 requires automatic sprinkler systems for buildings, based on the combustibility of building’s construction including structural elements, and the building’s floor area and height. Based on the window period, the Building Code requires additional sprinkler coverage of installations or alterations of automatic sprinkler systems in existing buildings; refer to Code Provisions (Fire Protection) below.

MD 7.2 IMD unit - Sprinkler System Requirements
See Code Requirements below.

MD 7.3 Manufacturing and Commercial Occupancies

  • Commercial & Manufacturing Spaces – §277.4requires wet-pipe sprinkler systems in manufacturing and commercial occupancies, and common and public spaces shared between different commercial, manufacturing and IMD occupancies.
  • Hallways and Stairways shared between manufacturing, commercial and IMD spaces - §277.4 and TPPN 9/93, item 5 also require wet-pipe sprinkler system in such shared spaces. Also, MD 6.3.1 and MD 6.3.2. 

MD 7.4 Smoke & Carbon Monoxide Detectors and Alarms - §277.7(g) requires smoke detectors with alarms outside each sleeping area. Such smoke detector alarms must also comply with BC 907.2 requirements for additional locations and UL listing and hardwiring. CO detectors must also be provided in accordance with BC 915.1.

MD 8 – Sanitation & Health

MD 8.1 Plumbing and Space Heating

§277.13 refers to various sections in Article 3, Title 3 of the MDL, which has various requirements for the plumbing and space heating of IMDs. AC 28-101.4.3, Exception 1 requires that all such systems be constructed and installed in accordance with the current New York City plumbing, fuel gas and mechanical Codes.

MD 9 – Waiver

MD 9.1 Waiver of MDL §277 Requirements for IMDs

§277.16 allows the Department’s Commissioner, or the Board of Standards and Appeals (BSA), to waive MDL §277 requirements. DOB further requires compliance with AC 28-103.3 and New York City Charter 645(b), i.e. practicable difficulty and an equally safe alternative, when considering such waivers, submitted on a Zoning or Code Determination form.

Code Provisions

As a supplement to the requirements in Article 7B of the MDL, the Code is applied in a limited manner.

Project Element


Applicable Code and  Regulations

Current Code

Prior Code





Application Filing

2022 AC 28-101.4.5 and 28-104.7

BC Chapter 1

2022 AC 28-101.4.3 -Optional Use of 1968 Code

(Optional use of 1938 Code* -
1968 AC §27-114)


The Loft Board’s establishment of IMD status also determines the period when such IMD was in existence. Based on window periods discussed in MDL sections §281.1, §281.4, §281.5 and §281.6, and as verified by the Loft Board, such IMD existence period determines the applicability of accessibility requirements as follows:

  • If the MDL window period is between 4/1/1980 and 12/1/1981, the IMD’s existence should be considered as prior to the effective date of Local Law 58 of 1987, and Accessibility Code requirements need not be applied.
  • If the MDL window period is between 1/1/2008 and 1/31/2009, the following Accessibility Code requirements mustbe applied. 
    • Window period between 1/1/2008 and 1/31/2009 - Any alterations to IMDs, as authorized by the Loft Board, are subject to Local Law 58 of 1987 at a minimum. The use of the 1968 building code is therefore allowed in accordance with 1968 AC 27-123.1, which has Local law 58 of 1987 text incorporated into 1968 AC section 27-292 and all subsections. Also see 1 RCNY 1101-01
    • Elevators (Window Period 1/1/2008 - 1/31/2009) –
      • 1968 AC 27-292.8 (b)(2)must be applied at a minimum, which would not mandate that an elevator be installed if the dwelling units on the ground floor are adaptable units, as set forth in such code section.
      • If the cost of alteration of an IMD building does not exceed the limit set forth in 1968 AC 27-123.1, any existing elevators must lead to an interior accessible route and, at a minimum must comply with all accessibility requirements in 1968 AC 27-292, which requires compliance with ANSI A117.1-1986.
  • If the MDL window period is between 1/1/2015 and 1/31/2020 (Chapter 41 of the NYS Laws of 2019, enacted 6/25/2019), the 2022 Code requirements for accessibility must be applied.

Occupancy Classification:
Building Use / Main Uses:
Residential (IMD)

Some Accessory Uses:

  • Mechanical and Electrical Equipment Rooms
  • Laundry Area
  • Offices
  • Storage
  • Home Occupation (Office)

BC Chapter 3

See PW-1 instructions for MD classification. Also see MD 1 above for relevant MDL sections.

Building Heights and Areas

1968 Code as referenced in MDL §277.2.

See MD 6 above

Construction Types

1968 code as referenced in MDL §277.2 and §278.

See MD 6 above


BC Chapter 10 and BC Appendix S

1968 Code as referenced in MDL §277.9 and §278.

See MD 4 above

Elevators and Conveying Systems

2022 AC 28-101.4.3BC Chapter 30 (General Provisions) and BC Appendix K.

  • Existing freight elevators
    • If a freight elevator is existing, and it’s the only elevator in a building having IMD units on upper floors, it mustbe converted to a Code-compliant accessible passenger elevator serving such dwelling units and/or common areas. Note that per BC 3001.11, such passenger elevator installed in existing shaft does not need to accommodate a stretcher.
    • Per BC 3001.4, if any existing freight elevator is changed to a passenger elevator use, where the passenger elevator shall access dwelling units and/or common areas of the building, such converted elevator mustalso comply with all passenger elevator requirements in Section 8.7 of ASME A17.1.

Also see Accessibility Code Provision, described above.

Fire Protection, Fire Districts

BC Appendix Q,
BC Appendix D,

The Loft Board's establishment of IMD status determines the period when such IMD was in existence. Based on the window periods discussed in MDL sections §281.1§281.4 and §281.5, and as verified by the Loft Board, such IMD existence period determines the applicability of fire protection system requirements as follows:

  • If the MDL window period is between 4/1/1980 and 12/1/1981, the IMD’s existence shall be considered as being prior to the effective date of Local Law (LL) 10 of 1999, and only the sprinkler coverage requirements in MDL 277 may be applied, at a minimum.
  • If the MDL window period is between 1/1/2015 and 1/31/2020 (Chapter 41 of the NYS Laws of 2019, enacted 6/25/2019), the 2022 Code requirements for fire protection system must be applied.

However, all components of any new, altered or added fire protection system must comply with NFPA 13, 14, 72, etc. requirements as amended by 2022 BC Appendix Q.

See MD 7 above.

Fire Resistance Rating

BC Chapter 7

1968 Code as referenced in MDL §277

See MD 6 above

Flood Resistant Construction

2022 BC Appendix G

Interior Environment

BC Chapter 12

1968 Code as referenced in MDL §277.

See MD 3 above

Interior Finishes

BC Chapter 8


BC Chapter 14 Chapters 19 to 26

Roof Assemblies and Rooftop Structures

Chapter 15

2022 BC where applicable and
1968 AC §27-338

Safeguards during Construction

  • Site Safety Plan

2022 BC Chapter 33

AC 28-110.1BC 3310

Energy Code Compliance

2020 NYCECC C503, C504
The Loft Board’s establishment of IMD status determines the period when such IMD was in existence. Based on the window periods discussed in MDL sections §281.1§281.4 and §281.5, and as verified by the Loft Board, the currently listed IMD existence periods, such de facto dwellings are prior to the 2011, 2014 and 2020 NYC Energy Conservation Codes (ECC).  As such only 2020 NYCECC C503 and C504 are applied, and any new, altered or added components must be energy efficient in accordance with the ECC.


BC Appendix F

Other Guidelines


See Building Systems: Boiler Guidelines

Building Pavement Plan (BPP)

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

Encroachments onto Public Right of Way

See Renovation: Public Right of Way Guidelines


See Renovation: Façade Guidelines

Foundations, Shoring, Underpinning

See Shoring/Underpinning of Foundations/Ground Structures


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


See Renovation: Storefront Guidelines

Zoning Provisions

Use Regulations

All two-family home types are UG 2, per ZR 22-11. There are limitations on locations of 2-family homes in Use Group 2 per ZR 22-12.

  • Residential Multiple Dwellings are Use Group 2, which is found in ZR 22-00
  • JLWQA is UG 17D, per ZR 42-14.
  • Commercial and Manufacturing Uses are classified per ZR 32-00 and ZR 42-00. They can be located in the same building as IMD, but only if allowed by MDL §281.5and Loft Board (Rule 29 RCNY 2-08, section k).
  • Other non-residential uses, such as community facilities, can be found in ZR 22-1032-10and 42-10
  • Accessory uses (ZR 12-10 “Accessory Use”) include, but are not limited to storage, offices, mechanical and/or electrical spaces, etc.
  • If the IMD is located within a zoning district where neither UG 2 nor UG 17D are permitted, such use shall be identified as non-conforming.
  • Home Occupation – As defined in ZR 12-10

Little (E) Designations

An (E) designation provides notice of the presence of an environmental restriction 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 approval (OER):

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

Refer to BB 2014-026ZR 11-15 and ZR Appendix C.

Bulk Regulation - Residential IMD legalization within Existing Buildings

Applicability – Conforming Use

IMDs located in zoning districts, where residential use is allowed by the by Zoning Resolution (ZR) regulations, shall be treated as existing non-compliant buildings. As such, the associated IMD alteration work, with respect to ZR bulk regulations, shall not increase the degree of existing non-compliance, nor create a new non-compliance. However, if there is a violation on record associated with such non-compliance, the building must be restored to either its original lawful bulk conditions or zoning compliant conditions.

Applicability – Non-conforming Use

IMDs located in zoning districts, where residential use is not allowed by the ZR regulations, shall be treated as existing non-complying and non-conforming buildings. As such, the existing non-conforming residential use may remain, and the associated IMD work, with respect to ZR bulk regulations, shall not increase the degree of existing non-compliance, nor create a new non-compliance.

Applicability – JLWQA

Parking Regulations – Residential

Because of IMD de facto multiple dwelling status, building or dwelling units are non-complying. Therefore, applicant need only provide a zoning analysis to indicate lawfully non-compliant parking conditions.

If additional voluntary parking is desired as part of design, Loft Board shall review such work’s impact to IMD tenants, as required by Loft Law MDL §281 and Rule 29 RCNY 2-08. Loft Board may require applicant to redesign to mitigate any adverse impact to tenants. In addition, ZR regulations, based on the zoning district, would be applicable to the design.

Other Regulation(s) for Reference

Housing Maintenance Code (HMC)

A New York State Law that establishes the minimum standards for health and safety, fire protection, light and ventilation cleanliness, repair and maintenance and occupancy in all residential dwellings and multiple dwellings, and which supplements the applicable New York City Code. Plans shall indicate applicable HMC notes to ensure compliance

Buildings Bulletins

  • BB 2008-001– Accessory Spaces Under 10% per Story
  • BB 2008-003– Mezzanine Floor Area Exemptions for Building Code
  • BB 2008-009– Incidental Use Areas and Accessory Occupancies
  • BB 2009-005– Exterior Exhaust Exemption for Electric Clothes Dryers
  • BB 2009-023– Smoke Detectors in Elevator Lobbies and Machine Rooms
  • BB 2014-026– Little (e) Designations/Environmental Restrictive Declarations
  • BB 2015-008– Easements and Restrictive Declarations
  • BB 2015-017– Opening in the Exterior Wall/Lot Line Windows
  • BB 2016-004– Historic Structures or Districts in Flood Zone Areas
  • BB 2016-012– Calculating Floor Surface Area
  • BB 2017-008 – Elevator Requirements, Including Ambulance Stretcher Accommodation and Standby Power
  • BB 2018-002 – Rooftop or Terrace Use
  • BB 2019-010 – Sustainable Roof Zone Requirements

Technical Policies and Procedures Notices

  • TPPN 9/93– Variations to Certain Requirements of Section 277 of the Multiple Dwelling Law for Interim Multiple Dwelling Buildings

Legal Policy and Procedure Notice (LPPN)

  • LPPN 2/92– Clarify procedures concerning the legalization of residential lofts covered as IMDs under the 1987 amendment to the MDL Article 7C


  • Memo 7-13-81– Issuance of TCO for JLWQA or General Residential Occupancy of Loft, Commercial or Manufacturing Buildings and /or final amended C of O.

Rules of the City of New York (RCNY)

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 site conditions and other components affected by the proposed scope of work. 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 2022 BC 107.2 and BC 1603.

The Department’s guidelines, provide an organized approach for the preparation of construction documents, facilitating the plan review process. Drawings shall clearly indicate existing site conditions and proposed conditions affected by the scope of work.

Complete Submission of Construction Documents

Construction drawings should represent complete work, including multiple disciplines such as architectural, structural, civil, plumbing, electrical, mechanical, fire protection, and others. There must be close coordination between all disciplines for the proposed scope of work to ensure code compliance; reference AC 28-104.7BC 107.2BC 1603 and Plan Examination Guidelines – Minimum Requirement for Review if Design Drawings, Revised 4-30-2014. A complete submission of drawings should include:

  1. Construction Documents.  Drawings and specifications necessary to convey essential information such as general notes, floor plans, elevations, building sections, schedules and details. Reference the applicable Construction Codes and notes on the drawings as required to demonstrate code and zoning compliance. Where essential to clarify overall layouts and details, a north arrow and a scale should be included on the drawings; a graphic scale recommended. Provide a title block with a 3-inch x 3-inch space for DOB approval stamp.
    • Title Sheet.  Should clearly describe the project location, including the adjacent streets, properties, block and lot numbers, and a graphical scale. Drawing notes should include the building name and address, names and contact information of all parties involved, occupancy classification, zoning use group, construction classification, the project’s scope, a list of related job filings/applications, a list of special and progress inspections, and the building’s primary structural system.
    • Drawing Index.A list to clearly identify the location of all associated construction drawings, sheet designations, page numbering and sequencing for post approval plans.
    • Site/Plot Plan.  Clearly indicate the size and location of the lot, show all existing and proposed structures on the zoning lot, and include all dimensions and other relevant information, such as but not limited to block and lot numbers, project address, street names street width, sidewalks and sidewalk width, street furniture, street trees and planting strips, Zoning District and Use Group, construction classification, Occupancy Classification, easements (egress, parking and utility), parking and loading, public utilities and features, adjacent buildings, curb cuts, north arrow and scale. Clearly identify the area of proposed work.
    • Zoning Analysis. Provide a tabular chart cross referencing all pertinent Zoning Resolution sections, such as corner lots or special districts with calculations showing compliance. The Zoning Analysis should provide the following.
      • Schematic dimensioned lot coverage diagrams;
      • Provide analysis for floor area, including schematic dimensioned diagrams indicating the gross floor areas of each floor, including identification of portions of the floor area to be deducted;
      • Schematic dimensioned building section(s) showing height and setback compliance;
      • Provide analysis for required accessory parking and loading;
      • Provide analysis for required bicycle parking;
      • Provide calculation for required street trees; and
      • Provide analysis for required and voluntary yards
    • Floor Plans.  Show proposed conditions; clearly identifying rooms’ names, dimensions, and square footages. Coordinate between all trades / disciplines to ensure that the proposed scope of work is complete and shown on all submitted discipline drawings. Where required, drawings must indicate wall types, including required fire ratings for partitions, ceilings, walls; location of penetrations through fire rated assemblies; accessibility compliance; code and zoning analysis cross references; light and air calculations; sprinkler/fire protection design; and life safety plans including travel distances, egress calculations and occupant loads.
    • Elevations.  Show all exterior elevations, including openings, fenestration, floor heights, head heights, control joints, adjoining grade levels compared with NAVD 88, foundation lines, exterior wall opening calculations, materials, zoning analysis cross references, chimney and vent heights and penetrations. Interior elevations may be required to demonstrate compliance with Code.
    • Building Sections.  Building cross sections, indicating adjoining grade levels, curb levels, base plane elevations, floor, stair, ceiling and roof levels, base flood elevation, foundation footings and required fire ratings (see also Shoring and Underpinning Guidelines).
    • Detail Drawings.  These drawings contain significant information required to communicate the scope of work, in a magnified form, including curb cut details, partition types, building’s thermal envelope, stair details, interior partitions, roofs, accessibility details with blow-up diagrams, millwork details and other elements unique to the building.
    • Schedule.  Door, window, column, finish materials and hardware schedules to indicate full scope of work
    • Building System Schedules.  Schedule of mechanical equipment showing make, model, capacity, fuel type, heat input/output, efficiency, maximum pressure, GPM, RPM, and electrical characteristics. See relevant Building Systems Guidelines (Mechanical, Plumbing, Sprinkler, and/or Standpipe) for more information.
    • Specifications. All manufacturers’ instructions and materials “cut sheets” for equipment and materials, as required.
    • 2020 NYC Energy Analysis.Energy Analysis shall be provided on pages labeled EN, with supporting documentation on architectural, lighting, mechanical and plumbing drawings. Provide Energy Analysis with location of supporting documentation in the drawings, including the corresponding values which must match the proposed construction. This should include the energy loads generated by process equipment specific to the manufacturing in the building. For projects claiming exceptions, information shall be provided in the analysis supporting the reason for the exception. Some key elements required on plans for all projects include:
      • Provide the correct Code reference citations to either 2020 NYCECC or ASHRAE 90.1 (2016).
      • Provide a professional statement indicating which code is being followed.
      • Provide a commissioning statement, where applicable, describing requirements for total building commissioning.
      • Energy Code Progress Inspections shall be listed on the EN drawings, based on the scope of work.
      • Energy Analysis shall be provided for all systems on drawings in the form of Tabular Analysis, COMcheck, or energy model (EN1). Energy Analysis references supporting documentation location and the corresponding values match the proposed construction on drawings. For projects claiming exceptions, details shall be clearly shown in the analysis supporting the reason for the exception.
      • Foundation and Exterior wall/roof/floor:
        • Opaque envelope assembly components are annotated with proper R-value and/or U-factors, and correctly calculated, including thermal bridging effects.
        • New vestibules shall meet envelope, heating and cooling provisions.
        • Loading dock weather-seals
        • Air-sealing details indicating construction and continuity of the air barrier to meet the requirements of the Air Barrier Continuity Plan.
      • Vertical glazing, skylights, doors:
        • Window and door schedules, including fenestration assembly U-factor, air leakage rates and solar heat gain coefficient (SHGC). Fenestration area (window/wall ratio) is clearly identified on drawings.
      • Lighting
        • Fixture Schedule shall be provided and include type designation, brief description, location of fixtures, lamp type, ballast/transformer factor, input watts per fixture, and controls scheme. Schedule shall be keyed to lighting plans (can be on the reflected ceiling plan). Lighting shall meet the lighting power density and mandatory controls requirements.
        • Daylight zones adjacent to vertical glazing and beneath skylights are clearly identified on the lighting plans.
        • Commissioning of lighting controls
      • HVAC
        • Equipment has met the sizing requirements.
        • Indicate equipment capacity, model number, rated efficiency and controls requirements (e.g. part-load, reset controls, pump modulation, demand controlled ventilation, economizers, energy recovery)
        • Indicate automatic shutoff damper with controls for outdoor air intakes and exhausts, stairwells and elevator shafts.
        • Identify duct insulation location, R-value, and details indicating joints and seams are sealed
        • Identify heating and cooling piping insulation location and thickness
        • Heating systems >600,000 BTU/h or Cooling systems > 480,000 BTU/h, thereby triggering the NYCECC commissioning requirement in addition to other requirements
      • Service water heating system(s)
        • Equipment performance efficiency
        • Service water efficiency
        • Circulation controls
        • Insulation and piping
      • Commercial refrigeration
        • Systems efficiencies and controls
      • Separating a conditioned space from an unconditioned space
      • Vestibules
      • Snow and Ice Melt System (radiant only with sensors and controls)
      • Loading Docks
      • Interior and Exterior Lighting
        • Mandatory lighting controls
        • Daylight sensors and controls, where applicable.
        • Lighting Power Densities
        • Electrical Energy Consumption
      • Mechanical ducts and related work
        • Insulation and sealing
      • Elevators
        • Elevator efficiency (Cab illumination and fans)
        • Motor efficiency
      • Sub-metering
      • Additional Efficiency Options (pick at least one as required in the NYCECC)
        • High efficiency HVAC performance
        • Reduced lighting power density
        • Enhanced lighting controls
        • On-site supply of renewable energy
        • DOAS Dedicated outdoor air system
        • High efficiency service water heating equipment
    • Accessibility for persons with physical disabilities to comply with BC Chapter 11
    • Façade and parapet walls with details
    • Lot Line windows replacement or new openings in accordance with permitted percentages
    • Interior elevations and details
    • Building systems and equipment details*
    • Flood zone compliance
    • Light and Air calculations for habitable rooms in residential projects
    • Site Safety Plans as required by scope of work
    • Current Site Survey prepared by a licensed land surveyor.
    • Builders Paving Plan (BPP) **
    • Laundry and Refuse chutes
    • Refuse and Trash Compactor Rooms
    • Accessible Dwelling or Sleeping Units Minimum Quantity Requirements

If applicable, additional elements required on drawings include:

*Refer to Construction Project Guidelines for building system projects.
**Refer to Project Guidelines for Builders Paving Plan.
Refer to Minimum Requirement for Review of Design Drawings available at the following link:

  1. Forms.  Per AC 28-104.7.2, when submitting construction documents to the Department, the applicant shall also submit forms provided by the department. Applicant shall ensure the information provided in all DOB forms matches the scope of work on construction documents. After the job is signed off, once CO issued, these dwelling units will be treated as existing non-conforming and/or non-complying, but no longer IMD.

The following items in PW1 and Schedule of Occupancy will be part of the final C of O, applicant shall double-check its accuracy:


    • CRFN number: Zoning exhibits, easement, or restrictive declaration
    • Occupancy Classification (proposed): Must provide the occupancy classification of dominate occupancy of the building using 2022 BC terms
    • Construction Classification (proposed): The terminology must match the year of “the earliest code with which this building or any part of it is required to comply”
    • Multiple Dwelling Classification: Must be CAA
    • Building Height (proposed)
    • Building Stories (proposed)
    • Dwelling Units (proposed): Must match the final number of dwelling units upon job completion.
    • The earliest code with which this building or any part of it is required to comply: must consider the effect of AC 27-118and AC 28-102.4.3 on the whole building
    • Fire Protection Equipment (proposed): Must match the final building-wide system upon job completion.
    • Open Spaces (proposed): Must match the final result of the site upon project competition, even if new parking is not proposed.

PW1A (proposed) or Schedule of Occupancy (DOB Now)

    • Maximum Number of Persons.Must match approved plan of each floor for maximum number of persons, non-residential portion of the building only.
    • Live Load. Must match the requirement of BC Table 1607.1. For example, residential is 40 psf, office is 100 psf, cellar/subcellar is OG.
    • Building Code Occupancy Group(s). Must use 2022 BC Chapter 3 Multiple occupancies on each floor shall write in separate line.
    • Dwelling/Rooming Units (BC). Must match the total number of dwelling units on each floor upon project completion. Duplex apartment shall use 0.5 units to add to total.
    • Zoning Use Group(s).  Must consider zoning use permitted as-of-right in your zoning district. For example, buildings located in M1-5A and M1-5B districts shall be UG 17D JLWQA; conforming or non-conforming residential use in other districts shall be UG 2A, accessory use shall be 2B.
    • Description. Must write the results upon project completion, such as five Class A Dwelling Unitstwo JLWQA Unitsupper half of Class A dwelling unitsfive retail stores, occupied roofpassive recreation only or unoccupied roof.

PW1A Building Notes to appear on the Certificate of Occupancy

    • CRFN number of zoning exhibits, easement, restrictive declarations.
    • History of IMD registration, such as dwelling units on the fourth floor were legalized under IMD registration #...
    • Non-conforming UG 2, if any, such as “dwelling units on the fourth floor is non-conforming residential use granted by IMD registration #...”
    • Limitations on size of Home Occupation, such as Unit 3A, 5B and 6A have home occupation subject to ZR 12-10.
    • Other restrictions, such as passive recreational roof subject to ZR 15-12, must remain accessible to all residential occupants.

Submission of Construction Documents

  1. Drawings.  The alteration project drawings should clearly reflect the scope of work and include all affected systems. All drawings for alterations per LL 49 of 2019 shall clearly include the following note: Alteration per LL 49 of 2019. Examples of this are as follows:

Designator - Sheet Number: Sheet Description
T-001.00       Title Sheet, Site Plan, Drawing Index, General Notes, required special/ progress inspections list, and Legends
A-101.00       Proposed Floor Plans
A-200.00       Proposed Reflected Ceiling Plans (if applicable)
A-300.00       Proposed Enlarged Floor Plans (if applicable)
A-301.00       Proposed Interior Elevations and Details (if applicable)
A-400.00       Existing and Proposed Façade Elevations
A-401.00       Existing and Proposed Cross Sections
S-100.00       Structural Plans and Details (if applicable)
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
M-100.00      Mechanical System Equipment and Schedules
M-101.00      Reflected Ceiling Plan for Mechanical System (if applicable)
EN-100.00    Energy Code Analysis (if applicable)
FS-100.00    Fuel Storage Equipment and Systems (if applicable)
EQ-100.00    Equipment (various, if applicable)

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.
DM: Demolition:
Mandatory designation for plans showing full or partial demolition 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
M: Mechanical: Mandatory designation for plans showing mechanical work
EN: Energy Analysis: Mandatory designation if an Energy Analysis is required

  1. Required Documents. Based on the building’s location and designation, and the project’s scope of work, the following submissions may have to accompany the drawings at intake:
    • Easements and Restrictive Declarations Form (BB 2015-008)
    • DEP – HCP and SCP forms for sanitary and storm water connections to street
    • OER authorization - as required by ZR (E) designation
    • FDNY – Fire Protection Plan
      • Smoke Detector Plan
      • Carbon Monoxide Detector
      • Fire Alarm: As-Built Plans
      • Notification, per FC 901.7.5, if doing construction work that impacts fire protection.
      • Letters of Notification if on a mapped undeveloped street
    • Mayor Office for People with Disabilities (MOPD) waiver
    • FEMA (Federal Emergency Management Agency) – Letter of Map Revision (LOMR) or Letter of Map Amendment (LOMA)
    • Transit Authority Approval, if applicable 
    • DOT Approval
    • LPC approval
    • Public Design Commission (PDC) approval
    • NYC DPR – ST1 (Street Trees)
    • City Planning – approval or certification if required by ZR
    • BSA approval
    • HPD approval - for inclusionary housing residences as required by ZR
    • DEC – if in coastal erosion hazard area or wetland areas
    • SRO (MD) Anti-Harassment checklist for residential Mayor’s Office:Waiver of some ZR Requirements under very limited circumstances
  2. Approval or Acceptance by Plan Review or Audits.
    • Plan Review - Following submission of a complete set of construction documents, the application is assigned for review to a DOB Plan Examiner.
    • Professional Certification - The Applicant of Record may professionally certify that a project’s design is in accordance with the NYC Code and all applicable Rules and Laws.
      • 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 revise-d document and /or plans for post approval amendment (PAA). Approval for an amendment is required 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).
    • Expanding or reducing the size or quantity of the project’s tax or zoning lot(s)
    • Changes to the zoning analysis including but not limited to addition or removal of floor space, floor area (as defined by ZR 12-10), and building height in the same or different story not shown on approved plans.
    • Change in Use Group or Occupancy Classification - An expansion of an occupancy classification or use group, or any similarly new use in an area not previously used for such purpose.
    • 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.
    • Structural changes
    • Expanding scope of work to add, replace or modify building equipment or roof systems
    • Increasing paved, or similarly impermeable areas
    • Changes in function of areas and rooms from what was shown on approved plans; for example, a portion of a living room is changed to a bedroom.
    • Changes to scope of work that require additional Special or Progress Inspection(s)
    • Adding or removing any accessory automobile parking spots or modifying the type of parking space (interior, exterior, or attended).
    • Adding or removing any accessory bicycle parking spots
    • Any modification to shape of building envelope
    • Any modification to building’s thermal envelope that impacts compliance with the Energy Code, such as modifying the exterior wall or roof system (insulation), or modifying the thermal quality of glass

NOTE: Revisions to drawings shall be clearly marked to highlight any of the above changes; the change should be bubbled, numbered and dated.

The following list, while not all-inclusive, is examples of some of the substantive changes that should be submitted for review to amend the approved plans:

  1. As-Built Submission.  Submit all changes 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.
(Visit for more information.)

Special and Progress Inspections

As per Chapter 17 of the Building Code, a New Building project 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 for correction to the superintendent of construction as well as to the site safety coordinator or site safety manager per BB 2016-006 and 1 RCNY 101-06. Per BC 1704.1.1.2, the contractor cannot hire the special inspector.

Based on the scope of work, a New Building project may be required to comply with the following Special and Progress Inspection requirements: (See BB 2022-014 for a more comprehensive Table)

Structural Steel

Required where structural steel construction is proposed, which include the following inspections: Open-Web Steel Joists and Joist Girders, Structural Steel - Welding, Structural Steel - High Strength Bolting, Cold Formed Steel and Structural Steel - Details (BC 1705.2).

Aluminum Welding

The Special Inspections for structural aluminum elements of buildings and structures shall be as required by BC 1705.33.


Required where concrete construction is proposed, with minor exceptions, which include the following inspections: Concrete – Cast-In-Place, Concrete – Precast, and Concrete – Prestressed, as per BC 1705.5. Also see BC 1905.6BC 1905.3, BC 110.3 and BC 1911.10.

Concrete Design Mix (TR3)

Concrete mix designs shall be in accordance with BC 1905.3 and BC 1911.5.

Concrete Sampling and Testing (TR2)

Concrete sampling and testing shall be in accordance with BC 1905.6 and BC 1911.10.


Load bearing masonry, glass unit masonry and masonry veneer shall be inspected and verified in accordance with the requirements of BC 1705.4.1 through 1705.4.3, depending on the structural occupancy category of the building or structure.

Vertical Masonry Foundation Elements

Vertical masonry foundation elements (i.e. CMU foundation walls) are subject to Special Inspections in accordance with BC 1705.19.

Wood – Installation of High-Load Diaphragms

Are subject to Special Inspections in accordance with BC 1704.1 and the requirements of BC Table 2306.2(2) (BC 1705.5.1).

Wood – Installation of Metal-Plate-Connected Trusses

Are subject to Special Inspections in accordance with BC 1704.1 (BC 1705.5.2).

Wood – Installation of Prefabricated I-Joists

Are subject to Special Inspections in accordance with BC 1704.2 and the requirements of BC 2303.1.2 (BC 1705.5.3).

Wood – Seismic Resistance

Required for seismic force-resisting systems of structures assigned to Seismic Design Category C or D, in accordance with BC 1705.5.5.

Type IV Construction (CLT/SCL)

Type IV construction utilizing cross-laminated timber (CLT) or structural composite lumber (SCL) elements are subject to special inspections in accordance with BC Table 1705.5.6.


Are subject to Special Inspections: Subgrade, Subsurface Conditions – Fill Placement & In-Place Density, and Subsurface Investigations (Borings/Test Pits) (TR4) in accordance with BC 1705.6. Borings and/or test pits shall be in accordance with BC 1803.5.

Wall Panels, Curtain Walls, and Veneers

Required for exterior architectural wall panels and the anchoring of veneers when any portion designed for installation on buildings exceeds 40 feet above grade.  Special Inspection of masonry veneer on such structures shall be in accordance with Section 1705.4 (BC 1705.20).

Sprayed Fire-Resistant Materials

Sprayed fire-resistant materials, applied to floor, roof and wall assemblies and structural members, shall be in accordance with BC 1705.14.

Mastic and Intumescent Fire-Resistant Coatings

Mastic and intumescent fire-resistant coatings applied to structural elements and decks shall be inspected and tested in accordance with BC 1705.15.

Combustible Exterior Wall Coverings

Installations and alterations to all exterior wall coverings containing combustible materials installed more than 15 feet above adjacent finished grades shall be in accordance with BC 1705.16.

Alternative Materials

Alternative materials shall be in accordance with BC 1705.1.1. The special inspection shall include the verification of compliance with approved construction documents and standards established by the commissioner pursuant to AC 28-113.2.2 of the Administrative Code.

Excavations– Sheeting, Shoring, Bracing

Methods employed to protect the sides of excavations, or to protect adjacent underpinned structures, shall be subject to Special Inspections in accordance with BC 1705.25.3.

Underpinning and alternate methods of support of buildings and adjacent property

Underpinning of structures and alternate methods of support of buildings and adjacent property shall be subject to special inspections in accordance with BC 1705.25.4, BC 1705.25.7 through 1705.25.10. and BC 1817.

Construction Operations Influencing Adjacent Structures

Construction operations having the potential to affect structurally the condition or occupancy of the subject structure and/or an adjacent structure are subject to special inspection as per BC 1705.25.2.

Mechanical Demolition

Where mechanical demolition equipment, other than handheld devices, is to be used in the full or partial demolition of a building from within the building, or is to be used within the building to remove debris or move material, such demolition operation shall be in accordance with BC 1705.25.5.

Private On-site Storm Water Drainage Disposal Systems and Detention Facilities Installation

Installations of on-site stormwater disposal systems and detention facilities shall be inspected in accordance with BC 1705.27.2.

Chimneys and Vents

Chimneys shall be subject to a special inspection in accordance with BC 1705.32.

Exhaust and Vent Systems in Plenums and Ducts

The installation of chimneys, vents, and exhaust systems under positive pressure that penetrate ducts and plenums shall be in accordance with MC 601.4 Exceptions 1 and 2, and tested as per BC 1705.39 and MC 810.

Fire-resistant Penetration and Joints

Special Inspections for penetration of fire-resistant elements and assemblies; and related firestops in accordance with Sections BC 1705.17.1 and BC 1705.17.2.

Tenant Protection Plan Compliance

Tenant Protection Plan is required when an alteration, partial demolition, or construction operations are performed at occupied multiple dwellings, in accordance with BC 1705.26.

Flood Zone Compliance


Special Inspection shall be as required for all work applications within the special flood hazard areas in accordance with BC Appendix G and BC 1705.34.

Raising and Moving of a Building

Special inspection shall be required where the lowest above-grade floor or lowest subgrade floor of a building is to be raised, lifted, elevated or moved in accordance with BC 1705.25.6 as well as BC 1705.25.7 through BC 1705.25.10 and BB 2015-010.

Luminous Egress Path Markings (TR7)

The installation of luminous exit path markings shall be subject to special inspection in accordance with the requirements of BC 1025.8 in accordance with BC 1705.35.

Footing and Foundation

Footing and foundation progress 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.

Deep Foundation Elements (TR5)

Installation and testing of deep foundation elements shall be subject to special inspections as specified in BC Table 1705.7.

Helical Piles Foundation (TR5H)

Installation of helical pile foundations shall be in accordance with BC 1705.9 and BB 2014-020.

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.

Post-installed anchors

The installation of post-installed mechanical anchors, adhesive anchors, and screw anchors shall comply with BC Table 1705.37BB 2014-018, and BB 2014-019.

Prestressed Rock and Soil Anchors

The installation and testing of permanent prestressed rock and soil anchors shall be subject to special inspections in accordance with BC 1705.8 and BC Table 1705.8.1.

Seismic Isolation Systems

There shall be periodic special inspection during the fabrication and installation of seismic isolation systems (isolator units and energy dissipation devices) in seismically isolated structures assigned to Seismic Design Category B, C or D, in accordance with BC 1705.12.5 and BC 1705.13.3.

Designated Seismic Systems

Required for designated seismic systems of structures assigned to Seismic Design Category C or D, in accordance with BC 1705.12.1.

Seismic Resistance of Plumbing, Mechanical, Fuel Gas, and Electrical Components

Required for anchorage and installation of plumbing, mechanical and electrical components in structures assigned to Seismic Design Category C or D, in accordance with BC 1705.12.3.

Seismic Resistance of Access Floors

Required for anchorage of access floors in structures assigned to Seismic Design Category D, in accordance with BC 1705.12.2.

Seismic Resistance of Storage Racks

Required for anchorage of storage racks that are 8 feet or greater in height in structures assigned to Seismic Design Category D, in accordance with BC 1705.12.4.

Structural Stability – Alterations of Existing Buildings

Alteration of existing structural systems or elements, such as columns, beams, bearing walls, etc. where the stability or integrity of a structural system is to be temporarily diminished, in accordance with BC 1705.25.1 and BC 1705.25.7 through 1705.25.10.


Preliminary inspections shall be in accordance with AC 28-116.2.1 and BC 110.2

Lowest Floor Elevation

In areas of special flood hazard, upon placement of the lowest floor, including the basement (for flood zone purposes), and prior to further vertical construction, the elevation inspection report required in Item 1 of G107.3 of BC Appendix G shall be submitted to DOB per BC 110.3.2.

Public Assembly Emergency Lighting

Progress Inspection for structures with proposed “places of assembly” in accordance with AC 28-116.2.2.

Luminous Egress Path Markings (TR7)

The installation of luminous exit path markings shall be subject to special inspection in accordance with the requirements of BC 1025.8 in accordance with BC 1705.35.


Final inspection is either required or optional, based on the scope of work, as per BB 2018-008 and in accordance with AC 28-116.2.4.

Energy Code Compliance Inspections

As required in BC 110.3.5, Energy Progress and Special Inspections shall be identified for Residential (Table I) and Commercial (Table II) buildings, as defined in 2020 NYCECC R202 and C202:

  • Protection of exposed foundation insulation:  to verify proper protection of below-grade walls and perimeter of slab-on-grade floors as per 2020 NYCECC R303.2.1
  • Insulation placement and R-values: to verify proper installation and R-values of insulation for each component of the conditioned space envelope as per 1 RCNY 5000-01 IA2 and IIA2.
  • Fenestration and door U-factor and product ratings: to verify conformance with U-factors, SHGC and VT values of installed fenestration as per 1 RCNY 5000-01 IA3 and IIA3.
  • Fenestration air leakage: to verify installed fenestration assemblies do not exceed the maximum allowed leakage rate as per 1 RCNY 5000-01 IA4 and IIA4.
  • Fenestration areas: to verify dimensions of windows, doors and skylights as per 1 RCNY 5000-01 IA5 and IIA5.
  • Air barrier – visual inspection: to verify proper sealing of openings and penetrations in the building envelope as per 1 RCNY 5000-01 IA6 and IIA6.
  • Air barrier – testing or Air barrier continuity plan testing: Third-party testing of the building’s air leakage rate as per 1 RCNY 5000-01 IA7 and IIA7 or IIA8.
  • Vestibules: to verify proper operation of required entrance vestibules as per 1 RCNY 5000-01 IIA9
  • Fireplaces: to verify provision of combustion air and tight-fitting fireplace doors as per 1 RCNY 5000-01 IB1 and IIB1.
  • Ventilation and air distribution systems: to verify ERV/HRV requirements or balanced ventilation system, along with whole-house ventilation fan efficacy, as per 1 RCNY 5000-01 IB2.
  • HVAC & Service Water piping design and insulation:  to verify correct insulation placement and values as per 1 RCNY 5000-01 IB5 and IIB5.
  • Metering:  The presence and operation of individual meters or other means of monitoring individual tenant spaces and apartments shall be verified by visual inspection per 1 RCNY 5000-01 IC1 and IIC1.
  • Lighting in dwelling units: to verify high-efficacy requirements of lamps in permanently installed light fixtures as per 1 RCNY 5000-01 IIC2.
  • Interior lighting power: to verify lighting power allowance of fixtures, lamps, ballasts and transformers, as per 1 RCNY 5000-01 IC2 and IIC3.
  • Exterior lighting power: to verify source efficacy and/or lighting power allowance as per 1 RCNY 5000-01 IIC4.
  • Lighting controls: to verify and test functionality and proper operation of required lighting controls as per 1 RCNY 5000-01 IIC5.
  • Electric motors and elevators: to verify with respective energy requirements for motors, elevators and escalators as per 1 RCNY 5000-01 IIC6.
  • Maintenance Information:  shall be furnished for installation of new equipment as per 1 RCNY 5000-01 ID1 and IID1.
  • Permanent Certificate:  shall list type and efficiency of heating, cooling, and/or service water heating systems as per 1 RCNY 5000-01 ID2.
  • Electric vehicle service equipment requirements:  to verify location and service with electric vehicle outlet or conduit as per 1 RCNY 5000-01 ID3.

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