Filing With the NYC DOB

by | Last updated Jul 14, 2020 | NYC DOB

Filing with the NYC DOB is a complicated and involved process with many protocols to take into consideration.


Types of Filing with the NYC DOB

Below is a list of the main filing types at the NYC Department Of Buildings. There are actually more but we will not get into every one here. There are the most common application you may file with he department of buildings.

  • NB New Building
  • Alt 1 Alteration Type 1
  • Alt 2 Alteration Type 2
  • Alt 3 Alteration Type 3
  • SI Subdivision
  • Demolition
  • Place of Assembly


NB New Building

A New Building Application or NB is filed by an architect for any new building weather you are building a single family house in NYC or developing a high rise building. This application is only if the new building is completely new if it incorporates any portion of an existing building then it is not a new building application.

Alt 1 Alteration Type 1

An Alteration Type 1 or Alt 1 is filed by an architect for any existing building to be altered where there is a change in Use, Occupancy, or Egress. This includes building conversions, most building enlargements, and renovations that change the means of egress in a significant manor. If you have an existing building and you demolish most of the building but keep a small portion and then rebuild bigger this is an Alt 1 not a NB.

Examples of Alteration Type 1 Project Filings:

Alt 2 Alteration Type 2

An Alteration Type 2 or Alt 2 is filed by an architect for renovations or alterations that do not change the Use, Occupancy, or Egress. Alteration Type 2 applications are also alterations with more than one work type for example general construction, plumbing, and electrical work are 3 separate work types. If you have 2 or more you would file an Alt 2.

Examples of Alteration Type 2 Project Filings:

We have another post you can read to learn more about Alt 1 and Alt 2 filing.

Alt 3 Alteration Type 3

An Alteration Type 3 or Alt 3 is filed by an architect for renovations or alterations that do not change the Use, Occupancy, or Egress and have only one work type. Alteration Type 3 applications are generally small very specific work types.

SI Subdivision

There are two types of Subdivision Filing applications. One is an improved property lot subdivision and the other is a condo lot subdivision. If you are planning to subdivide an empty plot of land you do not need to file with the Department Of Buildings you can file that directly with the Department of Finance. You will need an architect to file either way. A condo lot subdivision is when you are dividing individual Condominium Units in a building. An improved property subdivision is when you are subdividing a plot of land that has one or more structures on it. See another post we wrote to learn more about How to do a Condo Conversion.

DM Demolition

A Demolition filing or DM application is for full demolition of an existing building. Partial demolition or interior demolition would be filed in an Alt 1 or Alt 2 application.

Place of Assembly

A Place of Assembly or PA filing is filing for space with more than 75 people in an interior space or over 200 people in an exterior space. You can see another post we wrote to learn more about Place of Assembly Filing.


Filing with the NYC Department Of Buildings

As an architect I study building Codes and New York City regulations closely, but these are complicated and quite involved. In this article we reviewed some of the basic concepts with regards to NYC DOB Filing. This post does not assume to cover every possible issue or condition, but provide a general overview of the topic.


Thank you for reading our blog post on NYC DOB Filing.

I hope this was helpful. Please leave questions and comments below. If you would like to speak with an architect you can contact us directly.


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Jorge Fontan

Jorge Fontan

This post was written by Jorge Fontan AIA a Registered Architect and owner of New York City architecture firm Fontan Architecture. Jorge Fontan has earned 3 degrees in the study of architecture including two degrees from the City University of New York and a Masters Degree in Advanced Architectural Design from Columbia University. Jorge has a background in construction and has been practicing architecture for 20 years where he has designed renovations and new developments of various building types.