ADU Regulations:
Newton
Regulations Snapshot
Rear and Side setbacks: 5 feet
Building Separation: 5 feet
Height: 22 feet or 1.5 stories
Separate utilities required: No
Stormwater management required: Yes, if building over 400 sf
Specialized Stretch Energy Code: Yes
Impact Fees: $800 only if connecting new water/sewer to the street
Building Constraints
Number of ADU’s allowed on a single family lot
If you have a single-or two-family home, regardless of zoning district, you can add one ADU to the property. If you have any other residential use in a SR, MR, or BU1-4 district you can also add one ADU to the property. See like at bottom of page for Newton zoning map
Maximum square footage of an ADU (detached or attached)
New internal and detached ADUs are allowed by right up to 1,000 sf or 50% of the total floor area of the primary residence, whichever is smaller.
Detached ADUs where the existing structure (i.e. garage) were finalized at least 4 years prior OR the owner lives in either the main building or ADU are allowed by right up to 1,200 sf or 50% of the total floor area of the primary residence, whichever is smaller.
Maximum Height
If a detached ADU is no taller than 1.5 stories and 22 feet, it must have at least 5' side and rear setbacks. It must follow the same front yard setback rules as a regular single-family home. Detached ADUs can be up to 2.5 stories or 36’ They must meet the setback requirements for a single family, detached home in that particular zoning district.
Maximum lot coverage
None stated in bylaws
Exterior appearance requirements
Should respect the residential character of the neighborhood
Setbacks
Rear setback
5 feet
Side setback
5 feet
Front setback
Level with or behind primary dwelling
Distance between buildings
5 feet
Height
22 feet or 1.5 stories
Parking
Parking requirement for an ADU
No additional parking is required for the Accessory Dwelling Unit. If parking for the Accessory Dwelling Unit is added, however, screening is required sufficient to minimize t~e visual impact on abutters, such as evergreen or dense deciduous plantings, walls, fences, or a combination thereof
Specific parking requirements (location)
No
Where can the parking be located : Parking requirement for primary dwelling
N/A since ADUs do not require additional parking in Newton
Additional Requirements
Separate utilities required
No, can tap off the main house
Stormwater management required
Over 400 sf then trigger stormwater drainage requirements. Have to install drainage to capture additional stormwater. Have to hire an engineer to perform storm water analysis. The drainage depends on the quality of soil on the property.
Site plan review required
No
Town impact fees
If connect to new water/sewer hookups to the street then $800
Soils report required
If you trigger stormwater (building over 400 sf) then they want a soils report. It would be all in the same report as the soils, done by a civil engineer. It is advised to hire someone who’s done work in Newton because they have a strict stormwater policy.
Civil plans required
Yes
Short term rental allowed
No, ADUs are prohibited from being used as short-term rentals and must be rented for at least 30 days.
Possible overlay districts
Various historical districts, floor hazard zone, and floodplains
See link at bottom of page for Newton zoning map
ADUs on multifamily lots
If you have a single-or two-family home, regardless of zoning district, you can add one ADU to the property. If you have any other residential use in a SR, MR (Multi Residence), or BU1-4 district you can also add one ADU to the property.