4.1.1. 
Applicability. The regulations for each district pertaining to minimum lot area, minimum lot frontage, minimum lot depth, minimum front yard depth, minimum side yard depth, minimum rear yard depth, maximum height of buildings, maximum number of stories, maximum building area, and minimum open space shall be as specified in this section and set forth in the Table of Dimensional and Density Regulations,[1] and subject to the further provisions of this section, and for the Stoughton Center District (SCD) the information in this Section 4.0 is superseded by the information for the SCD in Section 9.3.
[Amended 5-2-2022 ATM by Art. 24]
[1]
Editor’s Note: The Table of Dimensional and Density Regulations is included as an attachment to this chapter.
4.1.2. 
Table of Dimensional and Density Regulations. See the Table of Dimensional and Density Regulations and Section 9.3.7, which are declared to be a part of this bylaw.[2]
[Amended 5-2-2022 ATM by Art. 24]
[2]
Editor’s Note: The Table of Dimensional and Density Regulations is included as an attachment to this chapter.
4.1.3. 
Reduction of lot areas. The lot, yard areas or open space required for any new building or use may not include any part of a lot that is required by any other building or use to comply with any provisions of this bylaw, nor may these areas include any property of which the ownership has been transferred subsequent to the effective date of this bylaw, if such property was a part of the area required for compliance with the dimensional regulations applicable to the lot from which such transfer was made.
4.1.4. 
Separation of lots. Lots shall not be so separated or transferred in ownership so as not to comply with the provisions of this bylaw.
4.1.5. 
One principal structure per lot. Except for planned developments for multifamily development, flexible development, planned unit residential development, planned business or industrial development, community facilities, and public utilities, only one principal structure shall be permitted on a lot. The minimum distance between the walls of such principal buildings shall be twice the minimum side yard or side setback required in the district. The minimum lot area required per each individual dwelling unit, building, or other unit of use shall be multiplied by the number of such units to obtain the minimum lot area required for the total tract of land. Other area regulations shall apply to the tract as a whole.
4.1.6. 
Shape factor.
1. 
No principal structure having a permitted use shall hereafter be erected or placed on any lot unless the lot is substantially regular in shape. "Substantially regular in shape" shall mean that a lot has a shape factor (SF) of 30.0 or less. Shape factor shall be determined by dividing the square of the perimeter of the lot measures in linear feet by the area of the lot measured in square feet: SF=(p x p)/A.
2. 
A lot may have a shape factor exceeding 30.0 if a portion of the lot itself meets the minimum lot area requirement and has a shape factor of 30.0 or less and which portion includes minimum street frontage.
3. 
The requirements of Section 4.1.6, Subsections 1 and 2, are hereby declared to be area and width requirements within the meaning of MGL c. 40A, § 6 (fourth paragraph, first sentence).
4.1.7. 
Lot width. Every lot created shall be configured so that it can contain a rectangle abutting the street line; said rectangle having a width equal to the required frontage, and having depth equal to the minimum required lot depth.
4.1.8. 
Lot width and frontage. Each lot shall have frontage on a street or way of the required minimum lot width, with its primary means of access onto said street or way. The principal means of access for residential lots shall be through said frontage.
4.2.1. 
Courts. Provisions for inner and outer courts shall be subject to the Building Code.
4.2.2. 
Corner lot. A corner lot shall have minimum street yards with depths which shall be the same as the required front yard depths for the adjoining lots.
4.2.3. 
Through lot. At each end of a through lot, there shall be a setback depth required, which is equal to the front yard depth required for the district in which each street frontage is located.
4.2.4. 
Projections. Projections into required yards or other required open spaces are permitted subject to the following:
1. 
Balcony or bay window, limited in total length to 1/2 the length of the building, not more than two feet.
2. 
Open terrace or steps or stoop, under four feet in height, up to 1/2 the required yard setback.
3. 
Steps or stoop over four feet in height, window sill, chimney, roof eave, fire escape, fire tower, storm enclosure, or similar architectural features, not more than two feet.
4.3.1. 
Exceptions. The provisions of this bylaw governing the height of buildings shall not apply to chimneys, cooling towers, elevator bulkheads, skylights, ventilators, electronic equipment, solar panels, elevator shafts, and other necessary appurtenances usually carried above a roof, not to domes, towers, stacks, or spires, if not used for human occupancy and which occupy not more than 20% of the ground floor area of the building; nor to ornamental towers, observation towers, radio broadcasting towers, television and radio antennas, and other like structures, which do not occupy more than 20% of the lot area; nor to churches or public agricultural or institutional buildings or buildings of private schools not conducted for profit that are primarily used for school purposes, provided that excepted appurtenances are not located within the flight paths of an airport as defined by FAA regulations.
4.4.1. 
Multifamily units. For multifamily units of two or more bedrooms, where the total number of dwelling units to be developed at one time or in any successive stages exceeds 12 dwelling units, there shall be an open space area with a minimum size of 500 square feet per unit for each two-bedroom unit and 1,000 square feet per bedroom for each unit of three or more bedrooms. Specifically exempt from this requirement are one-bedroom units and age-restricted housing under federal and state law.
4.5.1. 
General. For a multifamily apartment house, multifamily row house (townhouse or condominium) and two-family dwelling in the RM District, in addition to the requirements set forth in the Table of Dimensional and Density Regulations,[1] the minimum lot area shall be 12,000 square feet per dwelling unit and 2,000 square feet per bedroom per dwelling unit.
[1]
Editor’s Note: The Table of Dimensional and Density Regulations is included as an attachment to this chapter.
4.6.1. 
Buildings in floodway. A building shall not be erected in a floodway or any area subject to periodic flooding, except if the first floor elevation is higher than the highest flood recorded, unless such flood elevation shall have been reduced by construction of dams at headwaters, or by other means.
4.6.2. 
I and B Districts. Where an I or B District abuts an R District, no building within the I or B District shall be within 25 feet of the boundary line of the R District.
1. 
Within the twenty-five-foot setback there shall be a green belt no less than 15 feet in width running the distance where the I or B District abuts the R District. The Planning Board shall define the type, height and density of such plantings in its Rules and Regulations.
2. 
No building in a B or I District shall be constructed within 25 feet of the lot line of any residential home.
4.6.3. 
RM District. Where a lot in an RM District and/or multifamily dwelling units abuts or is within 100 feet of the boundary line of any single residence district and/or single-family dwellings a buffer strip shall be provided on all portions of said lot so abutting (within 100 feet as above said); such buffer strip to be at least 100 feet wide, including the width of any Town-owned land or public street. The buffer strip on said lot shall include a dense screen of vegetation no less than eight feet high and no closer than 15 feet from any intersection, and/or driveway-road intersection, and may be used only for access to the lot except that the Board of Appeals with due consideration to the effect on abutting lots may, in exceptional cases, permit up to 50 feet of the buffer strip most distant from the boundary line to be used for off-street parking subject to such additional screening conditions and requirements as the Board may determine are required. Nothing in this Section 4.6.3 shall be deeded to modify setback and yard requirements as otherwise provided in this Zoning Bylaw.
4.6.4. 
HB District. In an HB District, two or more contiguous lots shall be considered one lot for the purpose of calculating minimum open space under the Table of Dimensional and Density Regulations.[1]
[1]
Editor’s Note: The Table of Dimensional and Density Regulations is included as an attachment to this chapter.
4.6.5. 
Reduced side yard requirement in the RM and RU Districts. The Zoning Board of Appeals may grant a special permit to authorize a reduction of the required side yard in the RM and RU Districts by not more than 50%.
[Added 5-7-2018 ATM, Art. 51]