Can you build an ADU in Pelham, NY?

Detached Single-Family - Minimum living area runs by room count, from 900 sq ft for a single-family dwelling of two rooms or fewer to 1,000 at three rooms, 1,100 at four and 1,300 at five or more, and the first floor must enclose at least 1,200 sq ft in this district.

• On a corner lot the yard on the side street frontage is at least 25 ft.
• Where a quarter of the block frontage within 200 ft is already built on, the front yard extends to the average alignment of the two nearest buildings, up to 10 ft beyond the minimum, § 98-104C.
• A dwelling without a basement of at least 7 ft clear height covering half the first floor owes another 100 sq ft, § 98-111.
• A lot separately owned and not adjacent to other land in the same ownership on August 6, 1957 may take a single-family dwelling whatever its area and width, § 98-103.
• No building other than a garden shed, greenhouse, animal house or playhouse may be lower than 1 1/2 stories, § 98-12.
• A solar heating device may cover up to 10% of the rear yard if it stands at least 5 ft from every lot line, § 98-16C.

Detached Single-Family - On a corner lot 60 ft wide the yard on the side street frontage must be at least 15 ft, plus 6 in. for each foot of width beyond that, and it is never required to exceed 25 ft.

• A house of worship or other nonresidential principal building may cover 20% of the lot and owes 50 ft on each side and 75 ft at the rear.
• Minimum living area runs by room count, from 900 sq ft for a single-family dwelling of two rooms or fewer to 1,300 at five rooms or more, and the first floor must enclose at least 900 sq ft.
• A dwelling without a qualifying basement owes another 100 sq ft, § 98-111.
• Where a quarter of the block frontage within 200 ft is already built on, the front yard extends to the average alignment of the two nearest buildings, up to 10 ft beyond the minimum, § 98-104C.
• A lot separately owned and not adjacent to other land in the same ownership on August 6, 1957 may take a single-family dwelling whatever its area and width, § 98-103.
• A solar heating device may cover up to 10% of the rear yard if it stands at least 5 ft from every lot line, § 98-23C(2).

Detached Single-Family - On a corner lot 50 ft wide the yard on the side street frontage must be at least 10 ft, plus 6 in. for each foot of width beyond that, and it is never required to exceed 20 ft.

• A house of worship or other nonresidential principal building may cover 20% of the lot and owes 35 ft on each side and 60 ft at the rear.
• Minimum living area runs by room count, from 900 sq ft for a single-family dwelling of two rooms or fewer to 1,300 at five rooms or more, and the first floor must enclose at least 900 sq ft.
• A dwelling without a qualifying basement owes another 100 sq ft, § 98-111.
• Where a quarter of the block frontage within 200 ft is already built on, the front yard extends to the average alignment of the two nearest buildings, up to 10 ft beyond the minimum, § 98-104C.
• A lot separately owned and not adjacent to other land in the same ownership on August 6, 1957 may take a single-family dwelling whatever its area and width, § 98-103.
• A solar heating device may cover up to 10% of the rear yard if it stands at least 5 ft from every lot line, § 98-30C(2).

Detached and Semidetached Single-Family - A semidetached dwelling for not more than two families needs 75 ft of lot width and owes at least 15 ft on each side and 20 ft at the rear, instead of the figures shown.

• On a corner lot the side street yard is at least 15 ft, plus 6 in. for every foot of width beyond 50 ft for a single-family house or 75 ft for a semidetached one, up to 20 ft.
• Minimum living area runs by room count, from 900 sq ft for a single-family dwelling of two rooms or fewer to 1,300 at five rooms or more, and the first floor must enclose at least 900 sq ft.
• A dwelling without a qualifying basement owes another 100 sq ft, § 98-111.
• Where a quarter of the block frontage within 200 ft is already built on, the front yard extends to the average alignment of the two nearest buildings, up to 10 ft beyond the minimum, § 98-104C.
• A lot separately owned and not adjacent to other land in the same ownership on August 6, 1957 may take a single-family dwelling whatever its area and width, § 98-103.
• A solar heating device may cover up to 10% of the rear yard if it stands at least 5 ft from every lot line, § 98-37C(2).

Detached Single- and Two-Family - The figures shown cover a two-family dwelling as well as a single-family one, and on a corner lot 50 ft wide the side street yard must be at least 10 ft, plus 6 in. for each foot of width beyond that, up to 20 ft.

• A general medical or surgical hospital, or a parochial or other religious school, needs a special permit, may cover 30% of the lot and owes 35 ft on each side and 60 ft at the rear.
• Minimum living area runs by room count, from 900 sq ft for a single-family or two-family dwelling of two rooms or fewer to 1,300 for a single-family dwelling of five rooms or more.
• The first floor must enclose at least 900 sq ft, § 98-110, and a dwelling without a qualifying basement owes another 100 sq ft, § 98-111.
• Where a quarter of the block frontage within 200 ft is already built on, the front yard extends to the average alignment of the two nearest buildings, up to 10 ft beyond the minimum, § 98-104C.
• A lot separately owned and not adjacent to other land in the same ownership on August 6, 1957 may take a single-family dwelling whatever its area and width, § 98-103.
• A solar heating device may cover up to 10% of the rear yard if it stands at least 5 ft from every lot line, § 98-44C(2).

Detached Single- and Two-Family and Multifamily Houses - The figures shown are for a dwelling of one or two families. A multifamily house needs a lot of at least 10,000 sq ft and 100 ft of width, may cover 30% of the lot, owes 20 ft on each side and needs 1,600 sq ft of lot area for each dwelling unit.

• A nonresidential principal building needs a special permit here, a lot of at least 10,000 sq ft and 100 ft of width, may cover 30% of the lot and owes 20 ft on each side.
• Main multifamily buildings stand at least 40 ft apart, and 25 ft from their detached accessory buildings, § 98-53.
• In a multifamily house 2 1/2 stories high no dwelling unit sits above the second floor, and basement living quarters are only for the family of a janitor, superintendent or other maintenance employee.
• Every dwelling unit in a multifamily house needs 250 sq ft of usable open space with a minimum dimension of 10 ft, § 98-56.
• On a corner lot 50 ft wide the side street yard must be at least 10 ft, plus 6 in. for each foot of width beyond that, up to 20 ft.
• Minimum living area runs from 900 sq ft for a single-family or two-family dwelling and 500 sq ft for a multifamily unit with no separate rooms, rising to 1,300 and 900 by room count, § 98-109.1.

Detached Single- and Two-Family and Multifamily - The only yard this district requires is a 20 ft side yard along a side lot line that coincides with the rear lot line of another lot.

• No part of a building may stand nearer the Wolf's Lane or Sparks Avenue right-of-way line than 100 ft or 1 1/2 times its height above that line, whichever is more restrictive, § 98-62.
• A multifamily house needs a site of at least 10,000 sq ft and 100 ft of width, with one dwelling unit for each 480 sq ft of site area, counting units held for the owner's maintenance staff.
• Height is 65 ft or six stories above the nearest Wolf's Lane curb, whichever is more restrictive, and no point of a building may exceed twice its distance to the nearest Res B-1 boundary.
• Coverage is measured for all buildings across the whole site under development, at the elevation of the lowest residential floor, and nothing below that elevation counts, § 98-61.
• Every dwelling unit needs 150 sq ft of usable open space with a minimum dimension of 20 ft, § 98-68, and one parking space, § 98-69.
• Housing for people at least 65 years of age and their spouses may stand 10 ft from such a side lot line, and no more than 65% of it may be independent living.

Restricted Retail Uses - The figures shown are for a use other than a single-family or two-family dwelling. A single-family or two-family detached dwelling needs at least 5,000 sq ft of lot and 50 ft of width, 15 ft in front and 10 ft on each side, and may cover 70% of the lot.

• Such a dwelling may rise to 35 ft and 2 1/2 stories.
• A side lot line abutting a lot in a residential district owes 10 ft whatever the use, and except on a corner lot no side yard is required at all, though one that is provided must be at least 10 ft.
• A lot used only for nonresidential purposes needs 2,500 sq ft and 25 ft of width; residential or mixed use needs 5,000 sq ft and 50 ft, or 2,500 sq ft for a mixed use on a corner lot.
• Lot area for each dwelling unit is 1,600 sq ft, counting units held for the owner's maintenance staff, § 98-79.
• In a mixed building a residential story may cover 70% of the lot and a story used only for nonresidential purposes 81%, and nonresidential uses stay on the first or second story.
• Through the Business District Floating Zone the Board of Trustees may approve a site plan on a lot of at least 4,000 sq ft and 40 ft wide, with ground floor coverage up to 80%, 60 ft and five stories.

General Retail Uses and Multifamily - The figures shown are for a building other than a single-family or two-family dwelling. A single-family or two-family detached dwelling needs at least 5,000 sq ft of lot and 50 ft of width, 15 ft in front and 10 ft on each side, and may cover 70% of the lot.

• Such a dwelling may rise to 35 ft and 2 1/2 stories.
• A side lot line abutting a lot in a residential district owes 10 ft whatever the use, and except on a corner lot no side yard is required at all, though one that is provided must be at least 10 ft.
• A lot used only for nonresidential purposes needs 2,500 sq ft and 25 ft of width; residential or mixed use needs 5,000 sq ft and 50 ft, or 2,500 sq ft for a mixed use on a corner lot.
• Lot area for each dwelling unit is 625 sq ft, and land in an adjoining Res M district in the same ownership may count toward the unit total at 1,600 sq ft per unit, § 98-88.
• In a mixed building a residential story may cover 70% of the lot and a story in nonresidential use 86%, and nonresidential uses stay on the first or second story.
• Through the Business District Floating Zone the Board of Trustees may approve a site plan on a lot of at least 4,000 sq ft and 40 ft wide, with ground floor coverage up to 80%, 60 ft and five stories.

General Retail, Service and Restricted Industrial Uses - The figures shown are for a building other than a single-family or two-family dwelling. A single-family or two-family dwelling needs at least 5,000 sq ft of lot and 50 ft of width, 15 ft in front and 10 ft on each side, may cover 70% of the lot and may rise to 35 ft.

• A side lot line abutting a lot in a residential district owes 10 ft whatever the use, and except on a corner lot no side yard is required at all, though one that is provided must be at least 10 ft.
• A lot used only for nonresidential purposes needs 2,500 sq ft and 25 ft of width; residential or mixed use needs 5,000 sq ft and 50 ft, or 2,500 sq ft for a mixed use on a corner lot.
• In a mixed building a residential story may cover 70% of the lot, and a story in nonresidential use below a residential story 86%, with nonresidential uses on the first or second story.
• The 4 ft front yard and the 4 ft corner side yard may be increased or reduced by the Board of Trustees for consistency with adjacent buildings.
• Through the Business District Floating Zone the Board of Trustees may approve townhouses on a lot of at least 4,000 sq ft and 40 ft wide, with ground floor coverage up to 80%, 40 ft and three stories.
• Minimum living area runs by room count, from 900 sq ft for a single-family or two-family dwelling of two rooms or fewer to 1,300 at five rooms or more, § 98-109.1.

Office Buildings - The 150 ft front figure is the strip along the northerly street line of Sparks Avenue in which no building may be erected, and the 10 ft rear figure is the yard along the property line farthest from Sparks Avenue.

• Height drops to 40 ft or three stories, whichever is more restrictive, within 200 ft of the northerly side of Sparks Avenue.
• The office building is the only principal use this district permits.
• Product assembly and processing needs a special permit, must be wholly inside the building with no emissions beyond it, and is limited to 10 truck movements a day between 8:00 a.m. and 6:00 p.m.
• Parking at grade or in a structure of not more than two levels above grade is an accessory use.

Single- and Two-Family and Restricted Office Uses - The figures shown are for an office building. A single-family or two-family house follows the Res B-2 standards: a lot of at least 5,000 sq ft and 50 ft of width, 20 ft in front, 6 ft on each side and 16 ft for both, 25 ft at the rear, and 35 ft or 2 1/2 stories.

• Such a house may cover half the lot.
• The 50 ft front figure is the strip along the southerly street line of Willow Avenue in which no building may be erected.
• The 50 ft rear figure is the yard along the property line farthest from Fifth Avenue.
• Height for an office building drops to 40 ft or three stories, whichever is more restrictive, within 100 ft of the southerly side of Willow Avenue.
• Child day-care services and the Res B-2 special permit uses need a special permit.
• Parking at grade or in a structure of not more than two levels above grade is an accessory use.