[Amended 5-11-1994; 6-8-1994; 5-4-1995; 2-26-1997; 10-27-1999; 8-9-2000; 1-12-2005; 4-26-2005; 8-24-2005; 7-26-2006; 11-14-2007; 2-13-2008; 12-10-2008; 9-26-2012; 1-23-2013]
A. 
Part 402 is intended to provide for a compatible mixture of quality residential housing types within the Urban Development Area, consistent with the residential land use policies of the Comprehensive Plan. The plan identifies basic land use characteristics which are to be encouraged:
(1) 
Efficient land use patterns that create high-quality neighborhoods that are attractive and pedestrian oriented.
(2) 
Densities that promote a compact and efficient use of land.
(3) 
Reduced housing and public facility costs.
(4) 
Energy efficient housing and housing patterns.
(5) 
Sustainable and environmentally sensitive land use.
B. 
Within this Part 402, a number of general performance requirements are identified. When a housing development has satisfied these requirements, this Part 402 is intended to provide a large degree of flexibility in development and housing design. This design process is accomplished through a master development plan which is designed in cooperation with the County staff.
[Amended 3-13-2013; 10-13-2021]
C. 
It is the intent of this Part 402 to allow a mixture of housing types on the land within an approved master development plan. Within this Part 402, the permitted development percentages and densities for all housing types are identified. The master development plan shall specify the amount and percentages of all proposed housing types.
[Amended 3-13-2013]
D. 
While a mixture of housing types is allowed on a site, the intent is to use the master development plan and the other article regulations to place the different housing types on the site in a way that will protect the living environment of the new residents and existing residential land uses. It is the intention of this Part 402 to integrate new residential developments with existing residential developments and to ensure that different residential developments are properly screened from one another while still creating a sense of community and while providing for a variety of housing options. This Part 402 attempts to encourage the provision of some amenities through density bonuses, which are intended to enhance the development without increasing housing costs.
E. 
Streets shall be provided in new developments to continue existing and planned street patterns and in conformance with the Comprehensive Plan as well as any road improvement plans where appropriate and where necessary to achieve an interconnected street system. Streets and rights-of-way in proposed developments, intended to be developed in the future, shall be clearly designated to take into account future development as indicated in the Comprehensive Plan.
F. 
In those sections of this Part 402 where discretion is given to the Zoning Administrator, that discretion shall be exercised with this statement of intent as the primary guide for action.
A. 
All uses shall be developed in accordance with an approved master development plan unless otherwise waived under Article VIII of this chapter.
B. 
Structures and land shall be used for one of the following uses:
(1) 
All residential housing types specified in § 165-402.09.
(2) 
Schools.
[Amended 7-10-2024]
(3) 
Fire stations and companies and rescue squads.
(4) 
Group homes.
(5) 
Home occupations.
(6) 
Public utilities excluding energy-generating facilities.
[Amended 1-8-2020]
(7) 
Accessory uses and structures. Accessory structures attached to the main structure shall be considered part of the main structure. Mobile homes and trailers, as defined, shall not be permitted as accessory structures or buildings.
(8) 
Required or bonus recreational facilities, public or private parks, neighborhood parks, playgrounds, or other noncommercial recreational facilities.
(9) 
Business signs associated with schools, churches, fire stations and companies and rescue squads, recreational facilities, public parks, playgrounds, and libraries.
(10) 
Temporary model homes used for sale of properties in a residential development.
(11) 
Libraries.
(12) 
Public buildings.
(13) 
(Reserved)[1]
[1]
Editor's Note: Former Subsection B(13), Residential subdivision identification signs, was repealed 5-10-2023.
(14) 
(Reserved)[2]
[2]
Editor's Note: Former Subsection B(14), Signs allowed in § 165-201.06B, was repealed 5-10-2023.
(15) 
Temporary family health care structure. (NOTE: By adding temporary family health care structure as a permitted use in the RP District, it is also automatically a permitted use in the R4 and R5 Districts.)
[Added 8-14-2013]
(16) 
Short-term lodging.
[Added 9-28-2022]
(17) 
Churches and places of worship.
[Added 7-10-2024]
Uses and associated signs permitted with a conditional use permit shall be as follows:
A. 
Convalescent and nursing homes and adult care residences and assisted living care facilities.
B. 
Cottage occupations, as defined.
C. 
Nationally chartered fraternal lodges or civic clubs, social centers and their related club facilities.
[Amended 7-10-2024]
D. 
Day-care facilities.
E. 
Rooming houses, boardinghouses and tourist homes.
F. 
Veterinary offices, veterinary clinics or veterinary hospitals, excluding the boarding of animals for nonmedical purposes.
G. 
Museums.
H. 
Offices and clinics of doctors of medicine, dentists and other health practitioners.
[Added 7-12-2017; amended 12-13-2023]
More than one principal structure or use and its customary accessory structures or uses are permitted in the RP Residential Performance District for multiplexes, garden apartments, multifamily residential buildings and age-restricted multifamily housing.
A gross density shall be established for each proposed development, including all land contained within a single master development plan, according to the characteristics of the land, the capacity of public facilities and roads and the nature of surrounding uses. Because of these characteristics, some developments may not be allowed to employ the maximum density allowed by these regulations. The following density requirements shall apply to all parcels as they exist at the time of the adoption of this section:
A. 
Subsequent divisions of land shall not increase the allowed density on parcels of land.
B. 
In no case shall the gross density and maximum percentage of multifamily housing of any development within an approved master development plan exceed the densities and percentages set forth in the following table:
Density by Land Use
Density
(units/acre)
Maximum Percentage of Multifamily Housing
Multifamily residential buildings and age-restricted multifamily (excluding garden apartments)
20
100%
Garden apartments
10
100%
Townhouse (single-family attached)
10
N/A
Density by Parcel Size
(for all other housing types and development with mixed housing types)
(acres)
Density
(units/acre)
Maximum Percentage of Multifamily Housing
0 to 10
10
100%
10.1 to 25
6
100%
25.1 to 50
6
75%
50.1+
6
50%
C. 
Within developments utilizing transferable development rights, the maximum gross residential density for the development shall be determined in § 165-302.03H.
A. 
The developer/subdivider is permitted to construct the subdivision in phases or sections as long as:
(1) 
All sections are indicated on the master development plan and are of a size and at such a location that they constitute economically sound increments of development.
(2) 
Common recreational facilities and improvements and other improvements indicated for any phase section are required to be started not later than when that section reaches fifty-percent occupancy and are required to be complete by the time that section reaches sixty-percent occupancy.
(3) 
Provisions shall be made to incorporate all phases or sections of the planned development under one homeowners' association/corporation.
B. 
In order to provide sufficient, safe access, the Planning Commission and the Board of Supervisors may require that the phases be arranged so that essential street entrances to the development are provided in the initial phases of the development.
A. 
A minimum percentage of the gross area of any proposed development shall be designated as common open space. This open space shall be for purposes of environmental protection and for the common use of residents of the development. Such open space shall be dedicated to a property owners' association or to Frederick County. Open space shall be dedicated to Frederick County only with the approval of the Board of Supervisors. The Board of Supervisors may allow public libraries and public schools to be located within areas designated as common open space, provided that the proposed facilities are indicated on the original master development plan for the residential development. During the review of the master development plan, the Board of Supervisors shall ensure that the location of a proposed public library or public school is appropriate and that adequate buffers, screening and access are provided to prevent negative impacts to adjoining residential uses. Public libraries and public schools shall be dedicated to Frederick County. Developments which contain any of the following housing types shall provide open space as specified below:
Type of Development
Minimum Required Open Space
(percent)
Developments containing only single-family detached rural traditional housing
0%
Developments containing only single-family traditional or detached urban housing
15%
Developments in which no less than 60% of the dwellings are single-family detached traditional housing mixed with any other housing types
20%
Developments containing only single-family detached cluster or a mixture of single-family detached cluster and urban housing
25%
Single-family small lot housing
30%
All other residential developments
30%
Nonresidential uses (minimum landscaped area)
15%
B. 
No more than 50% of the required open space shall be within the following environmental areas: lakes and ponds, floodplain, wetlands or steep slopes. The Administrator, upon recommendation by the Planning Commission, may allow a larger amount of steep slopes to be utilized where the developer can demonstrate a viable plan to make these areas useful.
C. 
In developments containing only single-family detached urban housing or single-family detached urban housing mixed with single-family detached traditional housing, the required open space may be waived by the Board of Supervisors. The open space requirement shall only be waived when the required open space is less than one acre. Such waiver shall not include open space provided to meet environmental requirements.
D. 
The minimum required open space percentages provided in § 165-402.07A of this chapter may be reduced for residential developments which provide for active recreational areas and amenities, upon the granting of an open space waiver issued by the Board of Supervisors. In no case shall the required open space (per § 165-402.07A) be reduced more than 75% for single-family detached housing types (excluding single-family small lot) and no more than 50% for all other residential housing types and mixtures. Active recreational areas and amenities shall be incorporated within the development's common open space and be for the use of and maintained by the subject development's property owner's association. The active recreational area and amenity value shall be equivalent to the value of one recreational unit for each 30 dwelling units. The active recreational area and amenity value and design shall be approved by the Zoning Administrator in conjunction with the Director of Parks and Recreation. These open space active recreational areas and amenities shall be in addition to the minimum recreational facilities identified in § 165-402.08. The gross density requirements as required in § 165-402.05 shall not be exceeded through the reduction of common open space. Requests for an open space reduction waiver would be considered by the Board of Supervisors during the master development plan process. Acceptance of the reduced open space request will be based on the quality of the open space and the recreational amenities provided.
A. 
Single-family small lot, multiplex, townhouse, back-to-back townhouse, garden apartment and multifamily building housing types shall provide the following recreational units or equivalent recreational facilities for each 30 dwelling units. All such developments shall contain at least one such recreational unit. In addition, developments containing single-family small-lot housing shall provide a community center that provides for the equivalent of three age-appropriate recreational units for each 30 dwelling units. The facilities shall be in a configuration and location that is easily accessible and centrally located to the dwelling units that they are designed to serve. The design and amount of facilities shall be approved by the Zoning Administrator in conjunction with the Department of Parks and Recreation, using the following recreational unit as a guideline. The design of such facilities shall be approved at the time of site plan review.
(1) 
The Board of Supervisors may provide a waiver for the community center requirement specified in § 165-402.08A in single-family small-lot subdivisions that contain less than 25 lots. This waiver may be requested by the applicant during the consideration of the subdivision design plan if no master development plan is required. The applicant is required to demonstrate how an equivalent recreational value of three recreational units for each 30 dwelling units, prorated, is being provided within the project, to the County, or a combination of both as a condition of requesting approval of a waiver by the Board of Supervisors.
B. 
A recreational unit is designed to meet the recreational needs of 30 dwelling units. The units may be broken into smaller units or added together to meet the needs of the total development. An example recreational unit shall be as follows:
(1) 
Playground: composite play system for school-age children with a minimum of eight play features and one swing set.
Quantity
Equipment
Deck heights reaching at least 5 feet
Minimum 2
2- to 5-year-old play features
Minimum 1
Slides
Minimum 1
Climbing features
Minimum 1
Overhead features
Minimum 1
Tunnels
Minimum 1
Play panels
Minimum 1
Swings (8 feet high, 2 seats)
(2) 
Or any recreational facilities of equivalent monetary value which may include:
(a) 
Swimming pools.
(b) 
Tennis, basketball or multipurpose courts.
(c) 
Multi-use trails.
(d) 
Athletic fields.
(e) 
Picnic shelters, which shall include picnic tables, trash receptacles, and areas for outdoor cooking.
(f) 
Community center.
(g) 
Other recreational facilities.
The following dimensional requirements shall be met by uses in the RP Residential Performance District. The Zoning Administrator shall make the final determination as to the classification of housing types. Unless otherwise specified, all housing types shall be served by public sewer and water.
A. 
Single-family detached rural traditional. This dwelling type consists of a fully detached, large-lot single-family residence on an individual lot with private yards on all four sides, without public sewer and water. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area
100,000 square feet
A2 Minimum lot depth to width ratio
1:3
B. Building Setbacks
B1 From road right-of-way
60 feet
B2 Side
15 feet
B3 Rear
50 feet
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from road right-of-way
50 feet
C2 Side
10 feet
C3 Rear
35 feet
D. Minimum Parking
D1 Required off-street parking
2 per unit
E. Height
E1 Principal building (max)
35 feet
E2 Accessory building (max)
20 feet
B. 
Single-family detached traditional. This dwelling type consists of a fully detached, large-lot single-family residence with private yards on all four sides without required common open space. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area
15,000 square feet
A2 Minimum lot width at setback
80 feet
B. Building Setbacks
B1 From road right-of-way
35 feet
B2 Side
10 feet
B3 Rear
25 feet
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from road right-of-way
25 feet
C2 Side
5 feet
C3 Rear
15 feet
D. Minimum Parking
D1 Required off-street parking
2 per unit
E. Height
E1 Principal building (max)
35 feet
E2 Accessory building (max)
20 feet
C. 
Single-family detached urban. This dwelling type consists of a fully detached, single-family residence on an individual lot with private yards on all four sides. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area
12,000 square feet
A2 Minimum lot width at setback
70 feet
A3 Minimum lot width at road right-of-way
40 feet
B. Building Setbacks
B1 From road right-of-way
35 feet
B2 Side
10 feet
B3 Rear
25 feet
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from road right-of-way
25 feet
C2 Side
5 feet
C3 Rear
15 feet
D. Minimum Parking
D1 Required off-street parking
2 per unit
E. Height
E1 Principal building (max)
35 feet
E2 Accessory building (max)
20 feet
D. 
Single-family detached cluster. This dwelling type consists of a fully detached, single-family residence on an individual lot, with private yards on all four sides. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area
8,000 square feet
A2 Minimum lot width at setback
60 feet
A3 Minimum lot width at road right-of-way
30 feet
B. Building Setbacks
B1 From road right-of-way
25 feet
B2 Side
8 feet
B3 Rear
20 feet
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from road right-of-way
15 feet
C2 Side
5 feet
C3 Rear
10 feet
D. Minimum Parking
D1 Required off-street parking
2 per unit
E. Height
E1 Principal building (max)
35 feet
E2 Accessory building (max)
20 feet
E. 
Single-family detached zero lot line. This dwelling type consists of a fully detached, single-family residence on an individual lot. The building is set on one of the side property lines, with a maintenance easement on the adjoining lot. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area
6,000 square feet
B. Building Setbacks
B1 From road right-of-way
25 feet
B2 Minimum on-site building spacing (side)
25 feet
B3 Rear
25 feet
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from road right-of-way
15 feet
C2 Side
20 feet
C3 Rear
15 feet
D. Minimum Parking
D1 Required off-street parking
2 per unit
E. Height
E1 Principal building (max)
35 feet
E2 Accessory building (max)
20 feet
F. Supplemental Regulations
F1 A maintenance easement of 10 feet in width must be obtained on the lot adjacent to the zero lot line side.
F2 The opposite side yard must be maintained clear of any obstructions other than a three-foot eaves encroachment, swimming pools, normal landscaping, removable patio covers extending no more than five feet or garden walls or fences. In no case shall any encroachment other than a fence be placed within the required maintenance easement.
F3 The zero lot line side must not be adjacent to a road right-of-way.
F. 
Single-family small lot. This dwelling type consists of a single-family detached or attached residence on an individual lot. No more than two units may be attached together. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area
3,750 square feet
B. Building Setbacks
B1 From public or private road right-of-way
25 feet
B2 The front setback may be reduced to 15 feet, provided that the residential unit utilizes a rear alley for access and there are no driveways on the private or public road fronting the residential unit.
B3 Side
Detached option: 5 feet
Attached option: 10 feet
B4 Rear
15 feet
B5 Minimum building spacing
Attached option: 20 feet
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from private/public road
15 feet
Rear alley option: 10 feet
C2 Side (end unit)
5 feet
C3 Rear
10 feet
C4 Rear (from open space)
5 feet
D. Minimum Parking
D1 Required off-street parking
2 per unit
E. Height
E1 Principal building (max)
35 feet
E2 Accessory building (max)
20 feet
F. Supplemental regulations
F1. A minimum of 20 landscape plantings shall be provided on each individual lot. At least 1/4 of the landscape plantings shall be trees, with the remainder being shrubs. The trees shall be a minimum of two inches in caliper at time of planting, and the shrubs shall be a minimum of three.
F2. Detached accessory structures may not exceed 150 square feet.
G. 
Multiplex. A "multiplex" is an attached residence containing three to four dwelling units. Units may or may not have independent outside access. Units within multiplex structures may be arranged side to side, back to back or vertically. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area per unit
3,000 square feet
A2 Maximum site impervious surface ratio
0.50
B. Building Setbacks
B1 From road right-of-way
35 feet
B2 From parking areas or driveways
20 feet
B3 Side
15 feet from perimeter boundary
B4 Rear
25 feet from perimeter boundary
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from road right-of-way
25 feet
C2 Front from parking areas or driveways
15 feet
C3 Side
10 feet
C4 Rear
15 feet
D. Minimum Parking
D1 Required off-street parking
2 per unit
E. Height
E1 Principal building (max)
35 feet
E2 Accessory building (max)
20 feet
H. 
Townhouse; back-to-back townhouse. This dwelling type consists of a single-family attached dwelling unit from ground to roof, with individual outside access. Rows of townhouses shall contain no more than eight dwelling units in a group. Back-to-back townhouses shall contain no more than 16 dwelling units in a group. Dimensional requirements shall be as follows:
[Amended 5-25-2022]
A. Lot Dimensions
A1 Minimum lot area
1,500 square feet
A2 Minimum lot width
End unit: 22 feet
Interior unit: 18 feet
B. Building Setbacks
B1 From public or private road right-of-way
With garage: 25 feet
Without garage: 15 feet
B2 From off-street parking lot
15 feet
B3 Side
10 feet
B4 Rear
20 feet
Back-to-back option: N/A
C. Setbacks for unroofed decks, stoops, landings and similar features
C1 Front from off-street parking lot
10 feet
C2 Front from private/public road
15 feet
C3 Side (end unit)
5 feet
C4 Rear
5 feet
D. Minimum Parking
D1 Required off-street parking
2.5 per unit
E. Height
E1 Principal building (max)
40 feet
E2 Accessory building (max)
20 feet
I. 
Garden apartments. This housing type consists of buildings that contain multiple dwelling units that share a common yard area. The entire dwelling unit does not necessarily have to be on the same floor. Garden apartments shall be at least two stories high but no more than four stories and shall contain six or more units in a single structure, not to exceed 16 units within a single structure. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Maximum site impervious surface ratio
0.60
B. Building Setbacks
B1 From public road right-of-way
35 feet
B2 From private road right-of-way, off-street parking lot or driveway
20 feet
B3 Side (perimeter)
20 feet
B4 Rear (perimeter)
25 feet
B5 Rear for balconies and decks
20 feet
B6 Minimum on-site building spacing: Buildings placed side to side shall have a minimum distance of 20 feet between buildings; buildings placed side to back shall have a minimum distance of 35 feet between buildings. Buildings back to back shall have a minimum distance of 50 feet between buildings.
C. Minimum Parking
C1 Required off-street parking
2 per unit
D. Height
D1 Principal building (max):
55 feet
D2 Accessory building (max)
20 feet
J. 
Multifamily residential buildings. This housing type consists of multifamily buildings with a minimum of four dwelling unit entrances sharing an internal corridor per floor. The entire dwelling unit does not necessarily have to be on the same floor. External corridors are not permitted. Multifamily residential buildings shall only be located in areas designated in the Comprehensive Plan as neighborhood villages, urban centers or other areas planned for high-density residential. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Maximum site impervious surface ratio
0.60
B. Building Setbacks
B1 From public road right-of-way
35 feet
B2 From off-street parking lot or driveway
20 feet
B3 Side (perimeter)
50 feet
B4 Rear (perimeter)
50 feet
B5 Rear for balconies and decks
20 feet
B6 Minimum on-site building spacing: Buildings placed side to side shall have a minimum distance of 20 feet between buildings; buildings placed side to back shall have a minimum distance of 35 feet between buildings. Buildings back to back shall have a minimum distance of 50 feet between buildings.
C. Minimum Parking
C1 Required off-street parking
2 per unit
D. Height
D1 Principal building (max): 60 feet, provided that a multifamily residential building may be erected to a maximum of 80 feet if it is set back from road right-of-ways and from lot lines in addition to each of the required minimum yard dimensions, a distance of not less than one foot for each one foot of height that it exceeds the sixty-foot limit.
D2 Accessory building (max)
20 feet
K. 
Age-restricted multifamily housing. "Age-restricted multifamily housing" is multifamily buildings where individual dwelling units share a common outside access. They also share a common yard area, which is the sum of the required lot areas of all dwelling units within the building. Age-restricted multifamily housing shall only be permitted within proffered age-restricted developments. Elevator service shall be provided to each floor of age-restricted multifamily housing structures for use by residents and guests. Dimensional requirements shall be as follows:
A. Lot Dimensions
A1 Minimum lot area
3 acres
A2 Maximum site impervious surface ratio
0.60
A3 Maximum number of units per building
110
B. Building Setbacks
B1 From road right-of-way
60 feet
B2 From off-street parking lot or driveway
5 feet
B3 Side (perimeter): 100 feet from the perimeter boundary. An additional two feet from the perimeter boundary shall be added for every foot that the height of the building exceeds 40 feet when the adjacent use is single-family residences.
B4 Rear (perimeter): 100 feet from the perimeter boundary. An additional two feet from the perimeter boundary shall be added for every foot that the height of the building exceeds 40 feet when the adjacent use is single-family residences.
B5 Rear for balconies and decks
May extend 10 feet into a perimeter setback
B6 Minimum on-site building spacing: Buildings placed side to side shall have a minimum distance of 20 feet between buildings; buildings placed side to back shall have a minimum distance of 35 feet between buildings. Buildings back to back shall have a minimum distance of 50 feet between buildings.
C. Minimum Parking
C1 Required off-street parking
1.5 per unit
D. Height
D1 Principal building (max): The maximum structure height for any principal building shall be 40 feet. The Board of Supervisors may waive the forty-foot height limitation, provided that it will not negatively impact adjacent residential uses. In no case shall any principal building exceed 60 feet in height.
D2 Accessory building (max)
20 feet
L. 
Height for other uses. The height for all other uses not otherwise specified shall not exceed 45 feet.
M. 
Setbacks for accessory structures. Accessory structures shall be set back from all property lines a minimum of five feet, except for uses with a required enclosed yard.
N. 
Setbacks for other uses. The following setbacks shall apply to uses not otherwise specified:
(1) 
Front setback shall be 35 feet.
(2) 
Side setbacks shall be 15 feet.
(3) 
Rear setback shall be 50 feet.
O. 
Setbacks from business and industrial uses. All proposed structures shall be set back 50 feet from the boundary of land zoned for business or industrial uses or land currently containing business or industrial uses.
P. 
Pipestem lots. The use of pipestem lots is permitted for single-family detached traditional, single-family detached urban and single-family detached cluster lot types, if all of the following design requirements are met:
(1) 
The total number of pipestem lots in a residential development may not exceed 5% of the total number of lots.
(2) 
Pipestem lots shall have a minimum road frontage of 20 feet.
(3) 
Pipestem lot driveways shall access only one lot.
(4) 
Minimum yards shall be as follows:
(a) 
Front, side and rear yards: 20 feet.
(b) 
Accessory buildings: 20 feet.
(c) 
Side yard of lots adjoining pipestem driveway yard: 15 feet.
(5) 
Pipestem lot driveways shall not adjoin other pipestem driveways.
(6) 
Unless specified differently above, pipestem lots shall comply with all other regulations of the Frederick County Zoning and Subdivision Ordinances.