Is the "1% Rule" still accepted by the NYC DOB?

Q: Is the "1% Rule" still accepted by the NYC DOB?

A: The "1% Rule" was used in the past by Architects to enable a minor addition to an existing building which had not been enlarged previously, even if there was no available FAR left. This was typically granted as a Reconsideration by the Borough Commissioner.

However, there is nothing within the NYC Zoning Resolution to support this "1% Rule", and it was ultimately found by the DOB to be indefensible. The DOB has since stopped granting this Reconsideration.

Can I exhaust a Mechanical Unit out the Lot Line wall of a building?

Q: Can I exhaust a Mechanical Unit out the Lot Line wall of a building?

A: No. Per the below Code Section, from BC RS 13-1, "Installation of Air Conditioning and Ventilating Systems", an exhaust duct to the exterior shall terminate at or above the Roof of the building, or in an exterior wall adjoining a street, yard, or court.

However, where the Lot Line adjoins an adjacent lot that shall not be developed (eg: a Landmark Church or similar), it may be worthwhile to seek a Reconsideration, since there is little or no chance that the adjacent lot will be developed further.

Refer to excerpt from RS 13-1 below for full details:

2-3.4.3 To minimize the hazard from fires in other structures, an exhaust duct to the outdoor air shall terminate at or above the roof of the building or in an exterior wall adjoining a street, yard or court.

When terminated in an exterior wall, the exhaust duct shall be at least 10 feet above the sidewalk or ground and shall terminate at least 10 feet from any window in another building or from any window in a residential portion of the same building, or from any fire escape, exterior stair, or balcony.

No exhaust duct or outdoor air intake shall be located where conflict with the operation of an existing intake or other ventilating opening. Exhaust openings shall be provided with vanes or louvers constructed so as to direct the air away from windows, other openings, and pedestrians.

An outdoor air intake opening with gross area of more than 144 square inches shall be provided with fire dampers when such opening is located as follows:
(a) Less than 30 feet above grade.
(b) Less than 30 feet in any direction from any opening in another building.
(c) Less than 15 feet from a lot line.
(d) Less than 50 feet above and less than 50 feet in any direction from a roof of combustible material or a building in which the exterior walls are constructed wholly or partly of wood.

When required by the commissioner, approved heat actuated devices shall be installed at intake openings to shut down fans in case of an exterior fire.

Old Code Class 3-Non-Fireproof Construction

Q: What is the Definition of Old Code Class 3-Non-Fireproof Structures?

A: Old Code Class 3-Non-Fireproof Structures are structures made of incombustible materials or assemblies of materials inadequate to meet the fire resistive rating requiremetns of Class1 or Class 2 Structures:

-Exterior Walls are Masonry or Reinforced Concrete,-Interior Framing is partly ot wholly of wood or unprotected iron or steel.

3-hours: Exterior Bearing Walls, Floor construction above the Cellar or Basement including Columns (except in Residence structures 3 stories+Basement or less in height, and in other structures not over 4 stories or 40' in height).

2-hours: Exterior Non-Bearing Walls, where protection is required, Shafts & Required Stairways over 4 stories/40' in height.

1-hour: Exterior Non-bearing Walls, Shafts & Required Stairways in structures not over 4 stories or 40' in height

This section does not apply to private dwellings of 40' and 4 stories or less in height.Exterior walls of private dwellings of Class 3 Non-Fireproof constructionmay be constructed of incombustible materials having a fire resistive rating of at least 1-hour, provided the building does not exceed 1 story in height and is separated at least 4' from any lot line and from any building.

Old Code Class 2-Fire Protected Structures

Q: What is the Definition of Old Code Class 2-Fire Protected Structures?

A: Walls and Structural members are made of incombustible materials with the following minimum Fire Resistive Ratings:

3 Hours: Bearing Walls and Exterior Walls.

1 Hour: Structural Members which support walls or columns, Structural members in walls, Shafts (except as provided in C26-646.0), Bearing walls in Residence Structures not exceeding 35', Exterior Panel Walls, and Permanent Interior Partitions.

Old Code Class 1-Fireproof Construction

Q: What is the Definition of Old Code Class 1-Fireproof Construction?

A: Walls and Structural members are made of incombustible materials with the following minimum Fire Resistive Ratings:

4 Hours:Exterior Walls, Fire Walls, Party Walls, Piers, Columns, Girders carrying columns.

3 Hours:Other Girders, Fire Partitions, Floors including their Beams and Girders, Beams, Roofs, and Floor Fillings, Required Stairway enclosures (other than in Schools and structures under 100' high).

2 Hours:Exterior Panel Walls, Exterior Bearing Walls in Private Dwellings 35' or less in ht, and Required Stairways in Schools and structures less than 100' in height.

Permanent interior partitions shall be constructed of incombustible materials. The degree of fire resistance of other construction features in Fireproof Structures and acceptable materials shall be as per Article 11.

What is the largest Entry Foyer permitted in an Apartment?

Q: What types of spaces may be declared as a Foyer, with no Windows? What is the maximum size of an Entry Foyer?

A: Entrance Foyers to Dwelling Units do not require Legal Windows provided that they comply with MDL , Title 3, Light & Air, Section 31.5, excerpted below:

5. A portion of any apartment used as an entrance hall to such apartment may be designated as a foyer. Such a foyer shall not be considered a room if the department shall so permit and if either:

a. Its floor area does not exceed ten per centum of the total floor area of such apartment, or
b. Every room in such apartment exceeds in area the minimum required area of such room by more than twenty per centum and the floor area of such foyer does not exceed twenty per centum of the floor area of such apartment.

An entrance foyer is not a Code Habitable Room. Definition of Code Habitable Room is below from NYC BC Definitions:

HABITABLE ROOM:
A residential room or space, having the minimum dimensions required by §27-751 of article six of subchapter twelve of this chapter in which the ordinary functions of domestic life are carried on, and which includes bedrooms, living rooms, studies, recreation rooms, kitchens, dining rooms and other similar spaces, but does not include closets, halls, stairs, laundry rooms, or bathrooms.