Table 1: Zoning Ordinance Comparison for Non-Condo Single-Family/Two-Family Homes in Residence Districts as of 12/1/20
(Specs exclude rear lots; Count excludes condos & exempt homes;  S.P. =  Special Permit)
%  of all  Single/Two family detached homes built before 1954 [1] 81% Detached Single/Two-family Homes were built before 1954
 Median Year Built  = 1930
Average FY19 Value of all Single/Two Family Homes by Component Average Building Value= 487K ; Average Land Value=656K
Residential Zoning District Specifications for One/Two Family Houses
(SR1,SR2,….R4,N refer to Zoning Districts)
Current Zoning Ordinance
Most Recent (2/28/20) Adopted Version
  Proposed New Zoning Ordinance V3
(8/7/20, 9/11/20, 9/24/20) Drafts
SR1 SR2 SR3 MR1 MR2 MR3   R1 R2 R3 R4 N
Number of Non-Condo Single/Two-Family homes in Residence District 1,649 7,906 6,264 2,887 911 40   3,471 11,740 3,833 526 111
Single/Two family detached homes by right Single-Family Single/Two Family   Ambiguous [2] Single/Two Family
Single-Family attached homes Allowed in all Residence Districts with Special Permit, subject to restrictions in Section 6.2.3   Townhouse Sections allowed in N Residence District. No other attached side-by-side house types allowed.
"House Type" (A,B,C,D, Duplex) allowed in district; House Types are assigned to each lot based only on current house on lot and district.  A, B, C, D are assigned to existing single-families. The Duplex type is assigned to vertical (not side-by-side) two-families. The 277 side-by-side two families are not a valid house type in the proposed zoning, but are included in the counts. No "House Type" assignments or restrictions in current zoning   A,B,C,D B,C
D [S.P.]
B,C, Duplex
Maximum Residential Units Allowed Excluding Multi-Unit Conversions and Accessory Apartments 1 unit for Single-Family/2 units for Two-Family   1 unit House Type C, 2 units Duplex, Ambiguous maximum (1 or 2) units for  House Types A,B,D [2]
Multi-Unit Conversion Allowed for homes with required min sq. ft. dimensions assuming 100% residential use. Note that  required minimum areas per converted unit is affected by nonresidential use in building in proposed zoning. Conversion allowed to more than single family with SP for homes A) in existence on 12/2/1974, B) meeting lot size/unit  and "New Lot" frontage mins. [3.1.11] Conversion allowed to more than two family with SP for homes A) in existence on 5/7/79, B) with lot size >=5K/family [3.2.13]   Multi-unit Conversion allowed by right up to 6 units for House Types A,B,D: 1,200 sq. ft. required for each regular residential unit; 900 sq. ft. required for units with 100% Affordable/Sustainable Design Standard. More units allowed with S.P. [3.5.2 in 8/7/20 Draft.]
Accessory Apartments by right Allowed within, or on the lot of, single and two family detached houses in all residential districts, subject to size restrictions [Sec 6.7.1]   Internal accessory apartments allowed by right, detached allowed with S.P. [3.6.2 in 8/7/20 Draft]
Parking Requirements Two Spaces per Residential Unit   None Required for One or Two Units
Driveway Specifications
 (Proposed Ordinance: 9/24/20 Draft)
None Specified   Driveways must be <=10' wide at property line AND must be 3' from side set-back line. No parking allowed between the building front elevation and the street.
Special Permit Granting Authority V1,V2 [3] City Council after a review process conducted by the City Council's Land Use Committee.   Planning Board appointed by Mayor
Section 6 rulings dealing with nonconforming structures and uses   Zoning Board of Appeals (ZBA) appointed by Mayor
Maximum Number of Stories 2.5 stories by right ; 3 stories with S.P.   2.5 stories for House Type A,B; 1.5 stories for C, 1 story for D; 2.5 stories for Duplex
Maximum Building Footprint in Sq. Ft. None Specified   House Type A=2,400; House Type B=1,400; House Type C=1,200; House Type D=2,300; Duplex=1,800
Minimum House Front Width
 (Proposed Ordinance:  9/11/20 Draft)
  None House Type A: None
Other House Types: Max of 12' or 25% of lot width for R* Districts (40% for N) 
Minimum FRONT setback [4] On or after 12/7/53 40' 30' 25' 15'   25' 20' 10' 5' 0'
Before 12/7/53 25' 15'  
Maximum FRONT setback None Specified   None 40' 35' 25'
Minimum SIDE setback for detached homes On or after 12/7/53 20' 15' 10' 7.5'   20' 12.5' 10' 7.5'
Before 12/7/53 12.5' 7.5'  
Minimum REAR Setback 25' 15'   40' 30' 20' 15'
Minimum Lot Frontage for detached homes [5] On or after 12/7/53 140' 100' 80'   80' 60' 50' 40'
Before 12/7/53 100' 80' 70'  
Maximum Lot Frontage None Specified   None 110' 100'
Lot size minimum for Detached Homes in Sq. Ft.  [5] On or after 12/7/53 25K 15K 10K   All lot minimums and FAR specifications
 removed in proposed new ordinance
Before 12/7/53 15K 10K 7K  
Lot size minimum per unit  in Sq. Ft.  [5] On or after 12/7/53 25K 15K 10K 5K  
Before 12/7/53 3.5K  
Home Floor To Lot Area (FAR) Ratio Maximum applies to all single and two family homes, except rear lots : Formula based limit that decreases max FAR with increased lot size. 3 SELECTED ranges given. [6] Lots < 5K SF 0.46 0.46 0.48 0.58  
 Lots >=7K SF
and <15K SF
0.31 to 0.43 0.33 to 0.43 0.38 to 0.48 0.48 to 0.53 0.43 to 0.53  
 Lots >=25K SF 0.26 0.33 0.36 0.38  
[1] Newton has approx. 19,809 single/two-family homes, excluding condos and exempt homes. Of these non-condo homes, 19,657 are in Residence Districts in the current zoning and 19,681 are in Residence Districts in the proposed zoning.
[2] 8/7/20 Draft of proposed Article 3 specifies a "Maximum of (1 or 2) Residential Unit" in House Type's A,B,D. If the specification was a "Maximum of 2 Units," this would mean that two-families were allowed by right in all zoning districts. By stating it as a "Maximum of (1 or 2)" units, however, it's ambiguous whether the Draft is allowing 2 units in House Types  A,B,D in R1,R2. The specification is also accompanied by the confusing explanatory note that "Allowing two-units within these residential House Types can help achieve the City Council goals of increasing housing opportunity (citywide) in a form that matches and responds the existing residential building forms within Newton’s neighborhoods."  This makes it ambiguous if V3 is specifying or suggesting by right two-families.
[3] The change in Special Permit Granting Authority (SPGA) to the Planning Board (for projects < 20,000  Units) appears in 3.1.1.D in V1, V2. However, in V3, this is now marked "Reserved" with the explanatory note that "The Planning Department recommends that the discussion on who is the Special Permit Granting Authority, and at what scale of project, to happen when taking up Article 11 – Administration." Since  the SPGA has not been respecified and the single/two-family nonconformity rates are so HIGH, is keeping the SPGA V1,V2 spec in the table. 
[4]  References to 12/7/53 refer to lot creation dates. Assessors Database does not have lot dates, only "Year Built" for homes.
[5] In current ordinance, nonconformity in frontage or lot size does NOT trigger any special permit requirement for existing single and two family house construction [Section 7.8.2.A.1.a], but does limit lot subdivision and conversions. 
[6] In current ordinance, FAR (floor-to-area) is used to limit oversized houses. FAR could be adjusted downward in current ordinance to further limit size of new construction. Three selected FAR specification ranges are listed. Actual FAR tables have more range specifications.