Description: Generalized attribute values -- From the parcel data (Aquinnah FY22, Chilmark FY23, Edgartown FY23, Gosnold FY21, Oak Bluffs FY22, Tisbury FY22, West Tisbury FY23) the Assess Table was summarized based on unique Loc_ID for the 'first' owner zip code, the 'first' use code, the minimum year built, and the maximum year built. The summarized table for each town was joined to the building centroid points based on Loc_ID. For the field [YrRnd] a value of "S" (seasonal) was assigned to those buildings where the first owner zip code was NOT an MV or Gosnold zip code; all other building centroid points received a value of "YR" for year-round. This is a gross assumption.For the field [Res] a value of "R" (residential) was assigned to those buildings where the first use code began with a value of 1. All other building centroid points received a value of "NR" for non-residential. NOTE: Some 'residential' properties may be vacant but developable or undevelopable per the assessor.The field of [MinYrBlt] is based on the minimum year built for all records associated with that parcel in the Assess table in the parcel file geodatabase. This minimum year built value from the Assess table was copied into this Build Structure Points feature class based on the join field of [Loc_ID]. If there are multiple structures on a parcel, they all received the same Minimum Year Built.A similar process, as [MaxYrBlt], was followed to populate [MaxYrBlt].The Min & Max year built are provided for a quick & dirty/general gist/approximation as to when that structure was developed. You are encouraged to do more research if you are doing site specific analysis regarding development. A NOTE about the Assess Table that's in the Level 3 Parcel Geodatabases: The assess table will have multiple entries for each parcel only if there are multiple owners (such as a parcel containing condos). The assess table does NOT have multiple records if the parcel contains multiple buildings. The Year Built included in the Assess Table might be for the first structure developed on the property or maybe it's for the primary/largest structure on the parcel ...basically, it's anyone's best guess. Aside from reviewing the detailed property cards for every property, it's impossible to know which specific structure on the property the Year Built corresponds to. Regarding Use Code, it is possible that the use will vary based on the owner (doesn't happen often - but it happens). Simply extracting the 'first' use code where there are multiple records/owners for a parcel, this is just a quick & easy way to assign a plausible use to each structure on the parcel.A NOTE about the Structures: -- These could be a main house, a guest house, or a barn or shed or garage, etc. Any and All structures are included in this dataset.This dataset consists of 2-dimensional roof outlines ("roofprints") for all buildings larger than 150 square feet, as initially interpreted by a contractor (Rolta) for the whole area of the Commonwealth using DigitalGlobe ortho images obtained in 2011 and 2012, supplemented with LiDAR (Light Detection And Ranging) data collected from 2002 to 2011 for the eastern half of the state.The roofprints as delivered by Rolta were enhanced by MassGIS using Normalized Digital Surface Models (NDSMs) derived from the same LiDAR data. Other layers were used, including the Standardized Parcels, to aid in review, especially where LiDAR data were not available.In 2019, MassGIS refreshed the data to a baseline of 2016 and continues to update features using newer aerial imagery that allows MassGIS staff to remove, modify and add structures to keep up with more current ground conditions. Structures from the original compilation that are removed are stored in an "archive" feature class for edit tracking and historical purposes. Also in 2019, MassGIS replaced the polygons in Boston with data from the city. In March 2021, the layer was updated with 2017 and 2018 structure review edits along with the first data edits compiled atop spring 2019 imagery. In July 2021, MassGIS completed the statewide update based on 2019 imagery. In September 2022, MassGIS completed the statewide update based on 2021 imagery.Last updated on 9/19/2022.In ArcSDE the layer is named STRUCTURES_POLY.
Copyright Text: Rolta, MassGIS, City of Boston, Sept. 2022; Martha's Vineyard Commission - Oct. 2022 (conversion from polygons to points)
Generalized assessing attributes - Martha's Vineyard Commission - August 2023
Description: This dataset consists of 2-dimensional roof outlines ("roofprints") for all buildings larger than 150 square feet, as initially interpreted by a contractor (Rolta) for the whole area of the Commonwealth using DigitalGlobe ortho images obtained in 2011 and 2012, supplemented with LiDAR (Light Detection And Ranging) data collected from 2002 to 2011 for the eastern half of the state.The roofprints as delivered by Rolta were enhanced by MassGIS using Normalized Digital Surface Models (NDSMs) derived from the same LiDAR data. Other layers were used, including the Standardized Parcels, to aid in review, especially where LiDAR data were not available.In 2019, MassGIS refreshed the data to a baseline of 2016 and continues to update features using newer aerial imagery that allows MassGIS staff to remove, modify and add structures to keep up with more current ground conditions. Structures from the original compilation that are removed are stored in an "archive" feature class for edit tracking and historical purposes. Also in 2019, MassGIS replaced the polygons in Boston with data from the city. In March 2021, the layer was updated with 2017 and 2018 structure review edits along with the first data edits compiled atop spring 2019 imagery. In July 2021, MassGIS completed the statewide update based on 2019 imagery. In September 2022, MassGIS completed the statewide update based on 2021 imagery.Last updated on 9/19/2022.In ArcSDE the layer is named STRUCTURES_POLY.
Copyright Text: Rolta, MassGIS, City of Boston, Sept. 2022