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Building Footprints

Geometry Type: polygon

image

Table of Contents

         1. Identification
         2. Data Quality and Specifications
         3. Attribute Information

1. Identification


Purpose This feature class is used by the NYC DOITT GIS group to maintain and distribute an accurate 'basemap' for NYC. The basemap provides the foundation upon virtually all other geospatial data with New York.
Description Building footprints represent the full perimeter outline of each building as viewed from directly above. Additional attribute information maintained for each feature includes: Building Identification Number (BIN); Borough, Block, and Lot information(BBL); ground elevation at building base; roof height above ground elevation; construction year, and feature type.
Source(s) Annually captured aerial imagery, NYC Research of DOB records, or other image resources.
Publication Dates Data: 05/03/16
Last Update: Weekly
Metadata: 12/22/2016
Update Frequency: Features are updated daily by DoITT staff and a public release is available weekly on NYC Open Data. Every four years a citywide review is made of the building footprints and features are updated photogrammetrically.
Available Formats File Geodatabase Feature Class as part of the Planimetrics geodatabase and individual shapefile on the NYC Open Data Portal
Use Limitations Open Data policies and restrictions apply. See Terms of Use
Access Rights Public
Links https://data.cityofnewyork.us/Housing-Development/Building-Footprints/nqwf-w8eh
Tags Buildings, Building footprint, BIN, Structure

2. Data Quality and Specifications


Horizontal Coordinate System New York State Plane Coordinates, Long Island East Zone, NAD83, US foot; Vertical Datum NAVD 1988
Resolution NA
Spatial Coverage New York City, NY
Temporal Coverage For this dataset, the source imagery was captured on the following dates:
Manhattan - June 24, 2014
The Bronx, Brooklyn, Queens and Staten Island - April 1st through April 25th, 2014
Final delivery of all imagery - April 10, 2015
Using this orthoimagery, the planimetric base layers were updated citywide starting in March 2015 and were completed in February 2016.
Positional Accuracy Estimated positional accuracy for photogrammetrically updated features (those with GEOM_SOURCE = Photogrammetric) is +/- 2 feet and meets ASPRS Class 1 horizontal mapping standards and ASPRS vertical Class 2 accuracy specifications. The mapping standards deal with Root Mean Square (RMS) calculations that states if a random number of clearly identifiable surveyed ground control points throughout the project were compared to the mapped features, the RMS of the points would not exceed 2'. In layman's terms, 95% of the data is accurate to +/- 2'.
Features with GEOM_SOURCE = Other (Manual) are captured by heads-up digitizing using the most current orthophotography available (currently from Spring 2018). These will be somewhat less accurate than the photogrammetrically updated features. Features so identified are reviewed photogrammetrically every four years and updated as necessary.
Features Captured All buildings >400 sq. feet and taller than 12 feet. Buildings with <12 feet height but with BIN should be captured.
Buildings with BIN but <400 sq. feet will be captured.
Buildings with flat roofs will be captured on roof outline, capturing the largest outline (excluding overhangs, awnings, construction features, etc.).
Buildings with pitched roofs will be captured on the building footprint.
Carports, when attached to main building, will be included in the outline.
In cases where editors have no visual or plan information to digitize a footprint, a triangle symbol is used. These features are flagged as FEATURE_CODE = Placeholder.
Features Excluded Do not collect interior divisions (use existing building layer and BIN as guide).
Do not collect temporary trailers or tents. Do NOT collect roofs (overhang) to gas stations, unless connected to building.
Do NOT collect movable jet bridge for access to aircraft.
Do NOT collect awnings, scaffolds, or sidewalk sheds.
Do NOT collect small tool or storage sheds in backyards which have no visible car access. In cases where there is no BIN for a feature, a dummy BIN (1000000, 2000000, etc. for each of the Boroughs, see LION manuals pdf) will be populated until we can determine an actual BIN for the structure.
Capture and Update Notes Guidelines for Photogrammetric Update: Use parcel data and BIN as guidance for collection. Where the parcel data indicates that a building should be two or more geometries AND there is NO physical indication, split the building using the parcel lines. Where the parcel data indicates that a building should be two or more geometries AND there is a physical indication, split the building using the physical indications. In cases where geometry previously existed in the legacy data, populate all resulting geometries with the original BIN (BINs will be duplicated in these cases).
Use Parcel layer to place garages within parcel or at parcel boundary check for special cases where parcel boundary clearly crosses garage. In these cases, either split the garage using physical features, or use the property line where there is no distinguishing physical feature.

For more information on capture and update of the Building Footprints dataset, see Capture Rules

Guidelines for Manual Update: Features captured by manual update are digitized from the most recent aerial imagery available. In cases where no imagery is available, features are digitized using plan diagrams available from Dept. of Buildings. In cases where there is no imagery or plan source available, a triangle is added and FEAT_CODE is set to Placeholder. Ground elevations are taken from neighboring buildings or from nearby planimetric spot elevation point features. Roof heights are taken from Dept. of Buildings plan diagrams if available or measured from controlled terrestrial image sources. If no source is available, roof height is left zero or NULL.

3. Attribute Information


Attribute Description Field Type Sensitive Field (Y/N) Notes
BASE_BBL Borough, block, and lot number for the tax lot that the footprint is physically located within. text No
MPLUTO_BBL Borough, block, and lot number to be used for joining the building footprints data to DCP's MapPLUTO data, which aggregates data for condominium buildings using DOF's billing BBL. For non-condominium buildings the billing BBL is the same as the BASE_BBL. For condominium buildings the billing BBL may be the same for multiple buildings on different physical tax lots if they are part of the same billing unit for DOF purposes. text No
BIN Building Identification Number. A number assigned by City Planning and used by Dept. of Buildings to reference information pertaining to an individual building. The first digit is a borough code (1 = Manhattan, 2 = The Bronx, 3 = Brooklyn, 4 = Queens, 5 = Staten Island). The remaining 6 digits are unique for buildings within that borough. In some cases where these 6 digits are all zeros (e.g. 1000000, 2000000, etc.) the BIN is unassigned or unknown. double No
NAME Building name (limited to commonly known names). This field has not been actively maintained since the original creation of this dataset. text No
LSTMODDATE Feature last modified date date No
LSTSTATTYPE Feature last status type (Demolition, Alteration, Geometry, Initialization, Correction, Marked for Construction, Marked For Demolition, Constructed) text No
CNSTRCT_YR The year construction of the building was completed.
Originally this column was populated using the Department of Finance Real Property Assessment Database (RPAD). Beginning in 2017 this will be the first year the completed structure is visible in available orthoimagery. Records where this is zero or NULL mean that this information was not available.
double No
DOITT_ID Unique identifier assigned by DOITT. double No
HEIGHTROOF Building Height is calculated as the difference from the building elevation from the Elevation point feature class and the elevation in the interpolated TIN model. This is the height of the roof above the ground elevation, NOT its height above sea level. Records where this is zero or NULL mean that this information was not available. double No The units of measurement are based on the coordinate reference system used, which for all Planimetrics is New York State Plane Coordinates, Long Island East Zone, NAD83, US foot. All measurements in the attribute tables are in US foot. The building height information is updated through our planimetric updates every 4 years. In between those 4-year update cycles, DoITT manually updates building height information from a variety of sources -- (1) Final as-built heights as shown in plan drawings posted on Department of Buildings BIS website (2) EagleView Oblique imagery, direct measurements taken on photogrammetrically controlled aerial imagery (3) Cyclomedia imagery, direct measurements were taken on photogrammetrically controlled terrestrial imagery (for buildings less than 60’ tall, only)
FEAT_CODE Type of Building. List of values:
1000 = Parking
1001 = Gas Station Canopy
1002 = Storage Tank
1003 = Placeholder (triangle for permitted bldg)
1004 = Auxiliary Structure (non-addressable, not garage)
1005 = Temporary Structure (e.g. construction trailer)
1006 = Cantilevered Building
2100 = Building
2110 = Skybridge
5100 = Building Under Construction
5110 = Garage
long No
GROUNDELEV Lowest Elevation at the building ground level. Calculated from LiDAR or photogrammetrically. double No The units of measurement are based on the coordinate reference system used, which for all Planimetrics is New York State Plane Coordinates, Long Island East Zone, NAD83, US foot. All measurements in the attribute tables are in US foot.
GEOM_SOURCE Indicates the reference source used to add or update the feature. Photogrammetric means the feature was added or updated using photogrammetric stereo-compilation methodology. This is the most accurate update method and should conform to the ASPRS accuracy standards. Other (Manual) means the feature was added or updated by heads-up digitizing from orthophotos or approximated from a plan drawing. These features will be generally be less accurate and may not conform to the ASPRS accuracy standards. text No