[Added 9-5-1989 by Ord. No. 89-03]
A. 
In addition to the general goals listed in the statements of purposes and community development objectives, it is the purpose of this article to encourage and promote continued agricultural uses and conservation uses in the A-RT Zone, while also permitting residential development which will blend with existing agricultural uses, perpetuate the rural atmosphere of the area and provide for a transition area between agricultural and residential zones and also, by providing the option of utilizing the provisions in Article XV, Transferable Development Rights, to enable landowners within the A-RT Zone to elect not to develop all or a portion of their land but instead to obtain by the use thereof the economic benefits of development while at the same time covenanting to leave all or a portion of their land undeveloped in perpetuity.
B. 
It is further the purpose of this article to promote agricultural uses for the future while still permitting the population density as envisioned through transition cluster development in appropriate areas of the district associated with covenanting of remainders of tracts as agricultural land undeveloped in perpetuity.
C. 
Accordingly, the district incorporates standards which, among other things, provide for farm and dwelling uses, encourage cluster residential development and facilitate the conservation of agricultural and woodland areas, surface and undergroundwater supplies and the control of soil erosion and surface water flooding.
D. 
In the A-RT Agricultural-Residential Transition District, the following regulations shall apply.
A. 
Uses permitted by right. A building may be erected, altered or used and a lot or premises may be used, by right, for any of the following purposes and for no other:
(1) 
Single-family detached dwelling.
(2) 
Woodlands, game preserves or other conservation purpose.
(3) 
Agricultural uses, including nurseries and timber production in accordance with the provisions of farm regulations, § 122-93 of this chapter.
(4) 
Golf club or other outdoor recreational use customarily located in natural woodland and agricultural areas, including a country club or similar club or lodge in conjunction with any permitted outdoor use, provided that:
(a) 
The minimum area of the property on which the use is conducted shall not be less than 20 acres.
(b) 
The use and its design are compatible with the natural character of the area.
(c) 
Each structure shall be clearly incidental to the outdoor use.
(d) 
Any club or lodge building and its services shall be for the use of members and their guests only.
(e) 
No commercial activity or use, such as a campground, amusement park, pitch and putt course and like uses customarily carried on as businesses, shall be permitted.
(5) 
The sale or transfer of all or a portion of development rights apportionable in accordance with Article XV, Transfer of Development Rights, in the same manner and at the same intensities as for the R-A District, provided that the landowner by deed of easement shall totally and permanently restrict the future development of the tract or designated portion thereof from which the rights are sold or transferred and shall meet all other applicable requirements.
(6) 
Within those portions of the A-RT District designated as being within the historic area on the Historic District Overlay Map, the regulations contained in Article VIII shall be applicable.
(7) 
Forestry, provided that such use complies with all applicable standards in Chapter 101 of the Birmingham Township Code and with § 122-105.6.
[Added 6-18-2001 by Ord. No. 01-08]
(8) 
Group homes.
[Added 9-8-2014 by Ord. No. 14-04]
B. 
Uses permitted by special exception. Any of the following uses shall be permitted as a special exception when authorized by the Zoning Hearing Board, subject to the standards of Article XXI of this chapter:
[Amended 2-7-1994 by Ord. No. 94-01]
(1) 
Convent, monastery, church or similar religious institution, including a rectory or parish house.
(2) 
Riding academy or fox hunting club, provided that a minimum lot size of 20 acres shall be provided.[1]
[1]
Editor's Note: Original Subsection C, which immediately followed this subsection and dealt with home occupations, was repealed 2-7-1994 by Ord. No. 94-01.
C. 
Accessory uses. The following accessory uses shall be permitted, provided that they shall be incidental to any of the foregoing uses permitted by right or by special exception:
(1) 
Customary agricultural and residential accessory uses.
(2) 
Swimming pool, tennis court or paddle tennis court, provided that it is located behind the front facade of the house and building line and is set back at least 50 feet from any side or rear property line, and further provided that lighting facilities shall not interfere with the use and enjoyment of any neighboring property; provided, however, that the minimum setback from any side or rear property line with a lot containing less than 60,000 square feet and approved pursuant to either Article XVI or § 122-16 (Standards for farmside village development) of this chapter shall be 25 feet.
[Amended 7-23-2001 by Ord. No. 01-11]
(3) 
Private, noncommercial greenhouse.
(4) 
Artist's studio.
(5) 
Farm buildings.
(6) 
The sale of farm and nursery products in accordance with the provisions of § 122-94 of this chapter, Sale of farm products.
(7) 
Home occupation and no-impact home based business when in compliance with § 122-103.
[Amended 2-7-1994 by Ord. No. 94-01; 1-20-2003 by Ord. No. 03-01]
(8) 
Family day-care home, when in compliance with applicable provisions of §§ 122-103 and 122-104.
[Added 2-7-1994 by Ord. No. 94-01]
(9) 
An accessory apartment, provided that it is established in accordance with the standards set forth in § 122-13C(10).
[Added 4-10-2000 by Ord. No. 00-07]
D. 
Conditional uses. The following uses shall be permitted as a conditional use when authorized by the Board of Supervisors, subject to standards and procedures set forth herein and in § 122-119.
(1) 
Farmstead transition development for single-family residential subdivisions in accordance with the provisions of § 122-21 of this chapter, provided that the tract to be developed shall be 100 acres or more in gross area.
(2) 
Accessory farm structures and customary and agricultural and residential accessory uses.
[Amended 3-7-1991 by Ord. No. 91-02; 4-10-2000 by Ord. No. 00-06; 12-15-2003 by Ord. No. 03-07; 11-19-2007 by Ord. No. 07-02; 12-7-2020 by Ord. No. 20-05; 3-3-2025 by Ord. No. 2025-01]
The following area and bulk regulations shall be applicable to all uses with the exception of farmstead transition development, unless a specific area requirement has been specified for such use, which shall be governed by the regulations set forth in § 122-21:
A. 
Lot area. Every lot shall have a net lot area of not less than four acres. In computing the net lot area, driveways (whether individual or common access) are not netted out; streets (whether public or private) are netted out.
B. 
Lot width. Each lot shall have a width not less than 250 feet at the building line.
C. 
Impervious cover. Not more than 20% of the net lot area may be occupied by buildings or other impervious cover.
D. 
Front yard. There shall be a front yard of not less than 100 feet from the building line to the street line or 150 feet where the lot fronts on an arterial, collector or rural street.
E. 
Side yards. For every principal building, there shall be two side yards which shall not be less than 100 feet in aggregate width and neither of which shall be less than 40 feet in width.
F. 
Rear yard. For every principal building, there shall be a rear yard on each lot which shall be not less than 100 feet in depth.
G. 
Accessory buildings and structures. No accessory buildings or accessory structures, except a fence or wall below four feet in height, shall be situated within the front yard nor within 30 feet of any side or rear lot line or street line.
H. 
Height restriction. No building or structure shall exceed three stories or 35 feet in height, except that no accessory building, other than a farm building, shall exceed 20 feet in height.
The following design standards shall be applicable to the respective use categories as indicated:
A. 
Residential and agricultural uses permitted by right.
(1) 
Parking: as required by § 122-102A(2) of this chapter.
(2) 
Access and highway frontage: as required by § 122-102B(1) of this chapter.
B. 
Recreational uses by right and uses by special exception.
(1) 
Parking: as required by § 122-102A(1) of this chapter.
(2) 
Access and highway frontage: as required by § 122-102B(1) of this chapter.
(3) 
Landscaping: as required by § 122-102C of this chapter.
[Amended 12-15-2003 by Ord. No. 03-07; 7-10-2017 by Ord. No. 17-02; 3-3-2025 by Ord. No. 2025-01]
A. 
Eligibility and density. As a conditional use in the A-RT Zoning District, a developer may be allowed to modify area and bulk regulations, provided that the following procedures and conditions are met:
(1) 
The gross area of the tract to be subdivided shall be not less than 100 acres.
(2) 
The total number of new lots, in addition to the remaining farmstead tract as described in Subsection B and restricted as described in Subsection C hereinbelow, shall be determined in accordance with the following formula:
(a) 
Calculate the gross area of the tract.
(b) 
Subtract 50% of the tract area within identified floodplain areas and wetlands areas (measured concurrently where the two conditions coincide).
(c) 
Subtract 50% of the tract area having slopes in excess of 25% (measured over a vertical grade difference of six feet or more).
(d) 
Subtract the tract area to be devoted to existing and proposed street rights-of-way.
(e) 
Multiply the tract area in acres as modified by Subsections A(2)(b), (c) and (d) above as follows:
[1] 
For development utilizing on-site water and on-site sewer facilities, multiply by 0.375.
[2] 
For development utilizing either central water or central sewer facilities, multiply by 0.40.
[3] 
For development utilizing both central water and central sewer facilities, multiply by 0.425.
(3) 
For purposes of determining density, the utility classifications above shall be based on utilities serving the new lots only and the farmstead tract may continue to be served by on-site sewer and water facilities.
(4) 
The site shall be suitable for development in the manner proposed without hazards to persons or property on or off the site due to flooding, erosion, subsidence or slipping of the soil or other dangers or inconvenience. Conditions of soil, groundwater level, drainage and topography shall be compatible with the proposed site design. In the A-RT Zoning District, in addition to the above considerations, the site of new residential development within the tract shall, where possible, be restricted to that contiguous area of the tract with the least agricultural capability as determined by conditions of slope and soil standards. In addition, the site of the farmstead tract shall be located, where possible, so as to preserve the agricultural use potential of the farmstead tract and place new lots in closer proximity to adjacent tracts zoned for higher-density uses than to those zoned for agricultural preservation.
(5) 
In granting or denying a conditional use or establishing conditions on such grant, the standards set forth in § 122-119, where relevant, shall be applied. The burden of establishing compliance with such standards shall be upon the applicant. In addition, the following specific design standards shall be applicable:
(a) 
Parking: as required by § 122-102A(2) of this chapter.
(b) 
Access and highway frontage: as required by § 122-102B(1) of this chapter.
(c) 
Landscaping: as required by § 122-102C of this chapter.
(d) 
Screening: as required by § 122-102D of this chapter.
B. 
Area and bulk regulations. For farmstead transition developments, the new lots established shall consist of the following:
(1) 
Each of the lots allowed (except for the farmstead tract) shall conform to the following area and bulk regulations:
(a) 
Minimum lot size: 30,000 square feet.
(b) 
Minimum lot width: 125 feet at the building line.
(c) 
Maximum impervious cover: 25%.
(d) 
Minimum front yard: 45 feet.
(e) 
Minimum side yard (each): 25 feet, with an aggregate minimum of 60 feet for both side yards.
(f) 
Minimum rear yard: 50 feet.
(g) 
Accessory buildings: 25 feet (side yard or rear yard); 45 feet (front yard).
(2) 
After subtracting out areas devoted to new building lots conforming to Subsection B(1) and road rights-of-way (which shall not, in the aggregate, exceed 35% of the gross area of the tract), the remainder of the tract, which shall constitute at least 65% of the gross area of the tract, shall be divided into the following uses:
(a) 
A farmstead tract, to the extent feasible, centered upon farm buildings (either existing or to be constructed) pasture land and cropland, which shall have an area not less than 35% of gross tract area, a total building cover not exceeding 1.5%, total impervious cover not exceeding 2.5%.
(b) 
Common open space areas in conformity with the standards of § 122-85 of this chapter, which shall have a combined area not less than 17.5% of the gross tract area.
(c) 
The remaining 12 1/2% of the gross tract area (65% less the fifty-two-and-one-half-percent aggregate minimum areas for farmstead and common open space) shall be allocated between the farmstead and common open space in such proportions as the applicant may elect.
(3) 
The buffer area requirements of § 122-16B(3), relating to farmside village developments, shall also apply.
C. 
Restrictive covenants.
(1) 
As part of any conditional use approval for farmstead transition development in the A-RT District, the Board of Supervisors shall approve appropriate conditions restricting both the farmstead tract and the common open space areas against any future resubdivision or development and limiting the uses of each.
(2) 
The farmstead tract shall remain in private ownership, subject to the required declaration of restrictive covenants which shall be recorded in the Chester County Recorder of Deeds office. The declaration shall limit the uses of the farmstead tract in perpetuity to agricultural or forestry uses, not to be further subdivided or developed, except for agricultural accessory buildings as defined in this article and/or farm buildings as restricted in this chapter and one single-family residence.
(3) 
The common open space shall be subject to restrictions as specified in § 122-85E hereof.