§ 17.3.130 RESIDENTIAL DEVELOPMENT STANDARDS.

   A.   Residential development intensity/number of units.

      1.   The City of Forest Grove regulates residential development primarily by lot coverage based on building setbacks , permissible maximum building height and minimum lot size. All residential subdivisions in the SR, R-5 and R-7 zoning districts are required to meet the following lot averaging requirements:

         a.   SR Zone: Average of 43,560 square feet;

         b.   R-5 Zone: Average of 5,000 square feet;

         c.   R-7 Zone: Average of 7,000 square feet.

      2.   Maximum density does not apply to accessory dwelling units , duplexes , triplexes and quadplexes , however, the following limits apply to the division of a primary lot :

         a.   Accessory dwelling units : maximum of one per single-unit detached dwelling;

         b.   Duplex : maximum of two units per lot ;

         c.   Triplex : maximum of three units per lot ;

         d.   Quadplex : maximum of four units per lot .

      3.   Duplex , triplex , and quadplex units may be placed on an individual secondary lot through a middle housing land division . For a middle housing land division only one unit is allowed for each secondary lot .

      4.   Cottage clusters shall have at least three cottage units per cottage cluster  lot .

      5.   Townhouses shall have at least two attached units with individual lots created for each unit. The density for townhouse  development shall not exceed 20 units per net acre . No more than six units may be attached in a townhouse  development .

   B.   Minimum lot size and dimensions (R-7 and R-5 Zone). Varied lot sizes and housing types are permitted and encouraged within the R-7 and R-5 Zones.

   The city has established minimum lot size and dimensional standards to ensure that each lot has enough area for a house, garage , setbacks and private outdoor area. To ensure that development can be built near to and oriented toward the street , a minimum width at the front setback line is required.

   The minimum lot size is the smallest permissible size of a building lot . See Article 6 Land Divisions for additional lot  development standards.

Table 3-3: Lot Dimensional Requirements (R-5/R-7 Zones)[2]
Housing Type	Minimum Lot Size	Maximum Lot Size	Minimum Lot Dimensions [1]
R-5 Zone
Single-family detached	3,500 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Manufactured home	3,500 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Duplex	3,500 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Single-unit attached/townhouse	1,500 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Triplex	5,000 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Quadplex	7,000 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Cottage cluster	7,000 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Courtyard housing	7,000 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
Other uses	5,000 square feet	15,000 square feet	Depth: 60 feet	Width: 34 feet
R-7 Zone
Single-family detached	4,900 square feet	15,000 square feet	Depth: 75 feet	Width: 50 feet
Manufactured home	4,900 square feet	15,000 square feet	Depth: 75 feet	Width: 50 feet
Duplex	4,900 square feet	15,000 square feet	Depth: 75 feet	Width: 50 feet
Single-family attached/townhouse	1,500 square feet	15,000 square feet	Depth: 75 feet	Width: 25 feet
Triplex	5,000 square feet	15,000 square feet	Depth: 75 feet	Width: 50 feet
Quadplex	7,000 square feet	15,000 square feet	Depth: 75 feet	Width: 50 feet
Cottage cluster	7,000 square feet	15,000 square feet	Depth: 75 feet	Width: 50 feet
Courtyard housing	7,000 square feet	15,000 square feet	Depth: 75 feet	Width: 50 feet
Other uses	5,000 square feet	5,000 square feet	Depth: 75 feet	Width: 50 feet
Footnotes:    [1] Lot width is measured at the front building line.    [2] Minimum and maximum lot sizes apply to land divisions. Parcels larger than the maximum lot sizes shown in Table 3-3 are allowed for purposes of phasing development or reserving land for open space or undevelopable tracts.

 

   C.   Minimum lot size and dimensions (RM and RH Zones). Varied lot sizes and housing types are permitted and encouraged within the density ranges established for the RM and RH Zones. However, construction of new single-family detached units is restricted to existing lots smaller than 5,000 square feet in the RH Zone in order to retain land for multi-family housing.

Table 3-4: Lot Dimensional Requirements; RM and RH Zones
Housing Type	Minimum Lot Size	Minimum Lot Dimensions[1]
Single-family detached	3,000 square feet	Depth: 60 feet	Width: 35 feet
Manufactured home	3,000 square feet	Depth: 60 feet	Width: 35 feet
Duplex	3,000 square feet	Depth: 60 feet	Width: 60 feet
Single-family attached/townhome	1,500 square feet	Depth: 70 feet/65 feet[2]	Width: 20 feet
Triplex	5,000 square feet	Depth: 70 feet	Width: 50 feet
Quadplex	7,000 square feet	Depth: 70 feet	Width: 50 feet
Cottage cluster	5,000 square feet	Depth: 60 feet	Width: 35 feet
Courtyard housing	5,000 square feet	Depth: 70 feet	Width: 50 feet
Multi-unit	7,000 square feet	Depth: 70 feet	Width: 100 feet
Other uses	5,000 square feet	Depth: 70 feet	Width: 50 feet
Footnotes:    [1] Lot width is measured at the front building line.    [2] Depth allowed when vehicular access from a public alley

 

   D.   Setback standards. Building setbacks have an important relationship to the character of the street . Because varied lot sizes and housing types are permitted in the residential zones, uniform setbacks are established to provide a consistent streetscape.

Table 3-5: Minimum Setback Requirements
Housing Type	Front Yard to Dwelling	Front Yard to Garage/Parking Area	Interior Side Yard	Rear Yard
Single-unit detached	14 feet	20 feet	5 feet	15 feet
Duplex	14 feet	20 feet	5 feet	15 feet
Single-unit attached/townhouse	12 feet	20 feet	0 feet common wall construction 5 feet exterior wall at end of structure	0 feet adjacent to alley 10 feet no alley
Triplex and quadplex	12 feet	20 feet	5 feet	10 feet
Cottage clusters	12 feet	20 feet	5 feet	10 feet
Courtyard housing	12 feet	20 feet	5 feet	10 feet
Multi-unit structures	12 feet	14 feet	Buffer yard required based on adjacent use (§ 17.8.425 (Table 8-2))	Butter yard required based on adjacent use (§ 17.8.425 (Table 8-2))

 

Footnotes:

[1]   The side yard setback for attached single-unit dwellings /townhomes shall be a minimum of zero feet at common walls and five feet or one foot for each three feet of building height at the eave line, from the end of the unit series. Unless approved by the Director , the dwellings shall be arranged on lots in a manner that the non-zero setback portion for one lot shall be adjacent to the non-zero setback portion on the adjoining lot in order to provide greater continuous open space.

[2]   Accessory buildings (including accessory dwellings and detached garages) that do not exceed one story in height shall not be located closer than five feet to any side or rear property line.

[3]   Attached garages which exit to an alley may have a minimum rear yard setback of five feet.

[4]   A larger rear yard setback may be required for multi-family dwellings when the rear yard abuts a lower density residential zone. The need for a larger rear yard setback to provide privacy, access to sunlight and a transition between zones shall be evaluated in the design review process. The screening and buffering standards of Article 8 will be used as guidelines.

 

   E.   Building height. Building height standards are used to establish a compatible building scale. This can help to create a harmonious visual setting and helps to bring about a successful mixing of diverse housing types.

      1.   Buildings in the SR, R-7, R-5 and RM Zones are limited to a maximum height of two and one-half stories or 35 feet, whichever is less. Accessory buildings are limited to a maximum height of one and one-half stories or 25 feet, whichever is less.

      2.   Buildings in the RH Zone are limited to a maximum height of three stories or 45 feet, whichever is less. A step-down in building heights may be required for multi-family building(s) that abut a lower density residential zone. The need for a step down in building heights to provide privacy, access to sunlight and a transition between zones shall be evaluated in the Design Review Process.

      3.   A chimney, radio or television antenna , or device designed for the collection and/or generation of energy from the sun and/or wind may exceed the building height limit by a maximum of 15 feet.

      4.   Church steeples may exceed 35 feet in height through a Type II process.

   The maximum height is 15 feet above the building height limit in any location allowed by other requirements of the zone district.

   Church steeples may go to a maximum total height of 75 feet provided that setbacks of one foot for each one foot in height from the property line are maintained.

Figure 3-1

Step-down in Building Height

(Ord. 2009-0 1, passed 3-9-20 09; Ord. 2013-3, passed 5-22-20 13; Ord. 2017-12, passed 11-27-2017; Ord. 2019-05, passed 6-24-2019; Ord. 2022-01, passed 5-9-2022)