§ 16.60.010  GENERAL DEVELOPMENT STANDARDS.
   A.   Number of Principal Buildings on a Lot or Parcel.
      1.   In the agricultural and residential zoning districts, excluding the R-2 and R-3 Districts, a maximum of one (1) dwelling unit is permitted per lot or parcel. However, where allowed by the Ordinance, this does not apply to the presence of an ancillary dwelling unit.
      2.   In the R-2 District, a maximum of one (1) residential structure containing a maximum of two (2) dwelling units is permitted per lot or parcel. However, where allowed by the Ordinance, this does not apply to the presence of an ancillary dwelling unit.
      3.   In all other districts, multiple principal buildings may be erected on a single lot or parcel provided that each building complies with all bulk and setback requirements of the district. See § 16.56.030B.4.a. for additional rules for agricultural exempt structures.
      4.   The owner of a parcel may construct a replacement structure on the same lot or parcel prior to the demolition of an existing structure, provided that:
         a.   The replacement structure complies with all applicable bulk and setback requirements of the district.
         b.   The property owner enters into a legally binding agreement with the County stipulating that occupancy of the second structure is tied to a demolition schedule for the first structure.
         c.   The property owner posts a letter of credit in the amount of one hundred fifty percent (150%) of the cost of demolition and removal of the first structure, in a form approved by the Zoning Enforcement Officer. This letter of credit may be redeemed by the County if the property owner defaults on the agreement.
   B.   Frontage on a Public or Private Street. All lots and parcels shall front on a public or private street.
   C.   Required Setbacks. Required setbacks are measured as the minimum dimension required by a zoning district measured from the applicable lot lines (see Figure 16.60-1: Required Setbacks). Required setbacks are defined as follows:
      1.   The required street setback extends along the front and corner side lot lines between the front, interior side, and rear lot lines, for the required minimum depth specified by the zoning district in which the lot is located, measured perpendicular to the applicable lot line.
Figure 16.60-1:  Required Setbacks
 
         a.     For residential uses in the agricultural and residential zoning districts, the minimum required street setback is established in Table 16.36-1 . However, the required street setback may also be established by either of the following alternate methods:
            (1)   The platted street setback.
            (2)   The average of the street setback of existing homes on the same side of the blockface when sixty percent (60%) of the blockface is developed. For blockfaces that extend more than six hundred (600) feet, only parcels located within three hundred (300) feet of either side of the lot shall be considered.
      In no case shall a street setback be reduced to less than ten (10) feet, unless granted by a zoning variation.
      2.   The required interior side setback extends along an interior side lot line between the front and rear setbacks, for the required minimum depth specified by the zoning district in which the lot is located, measured perpendicular to the interior side lot line.
         a.    On nonconforming lots or parcels of record, setbacks for single-family dwellings and residential accessory structures may be reduced from the setbacks established by the bulk and setback tables of this Ordinance, per § 16.80.050D. (Reduced Setbacks).
         b.    On lots or parcels with an interior side lot line that abuts a body of water or waterway, principal and accessory structures are allowed a zero-foot (0') waterfront setback, subject to the McHenry County Stormwater Management Ordinance.
      3.   The required rear setback extends between the side lot lines for the required minimum depth specified by the zoning district in which the lot is located, measured perpendicular to the rear lot line.
         a.   On lots or parcels with a rear lot line that abuts a body of water or waterway, principal and accessory structures are allowed a zero-foot (0') waterfront setback, subject to the McHenry County Stormwater Management Ordinance.
      4.   Permitted encroachments are described in Table 16.60-1: Permitted Encroachments. An encroachment is the extension of an attached accessory structure or architectural feature of a principal dwelling into a required setback as listed in Table 16.36-1: Zoning Districts Bulk and Setback Regulations or as allowed under § 16.80.050D. (Reduced Setbacks).
         If the principal dwelling is a nonconforming structure, the amount it encroaches into the required setback in Table 16.36-1 is added to the allowed encroachment amount granted in Table 16.60-1 . With the exception of accessibility ramps, encroachments shall not result in an attached accessory structure or architectural feature being constructed closer than ten (10) feet from a street lot line, fifteen (15) feet from a corner side lot line, or five (5) feet from an interior side or rear lot line. Encroachments into recorded easements are prohibited without the express written permission of the easement holder(s) to which the easement is granted.
 
TABLE 16.60-1:  PERMITTED ENCROACHMENTS
Y= Permitted  //  N= Not Permitted
Attached Accessory Structure or Architectural Feature
Front Setback
Corner Side Setback
Interior Side Setback
Rear Setback
Accessibility Ramp
- No encroachment restrictions
Y
Y
Y
Y
Air Conditioner Window Unit
- No more than 18" into a required setback
Y
Y
Y
Y
Air Conditioner/HVAC Condensing Unit/Generators
- No more than 3' into a required setback
N
Y
Y
Y
Awning and Canopy
- Minimum clearance of 7'6"
- No more than 2' into a required setback
Y
Y
Y
Y
Balcony
- Shall be located at least 2' above ground
- No more than 4' into a required setback
Y
Y
Y
Y
Bay Window
- No more than 3' into a required setback
Y
Y
Y
Y
Carport
- No more than 5' into a required setback
N
Y
Y
Y
Chimney
- No more than 24" into a required setback
Y
Y
Y
Y
Deck, Patio (>4" above grade), or Pergola
- Shall be unenclosed
- No more than 5' into a required setback
Y
Y
Y
Y
Eaves of the principal structure
- No more than 4' into a required setback
Y
Y
Y
Y
Exterior Stairwells
- No more than 5' into a required setback
N
N
Y
Y
Fire Escape
- No more than 5' into a required setback
Y
Y
Y
Y
Porch
- Shall be unenclosed
- No more than 5' into a required setback
Y
Y
Y
Y
Sills, belt course, cornices, and ornamental features of the principal structure
- No more than 3' into a required setback
Y
Y
Y
Y
Steps and stoops
- No more than 10' into a required setback
Y
Y
Y
Y
 
   D.   Effective Yards. An effective yard is the space located between a structure and the adjoining lot lines. (See Figure 16.60-2: Effective Yards.) In this Ordinance, certain accessory structures are prohibited from locating within effective yards. The distinction is made because certain principal buildings may be set back further than required by district standards, thereby creating a yard larger than the minimum required setback dimension.
      1.   The effective street yard extends from the closest point of the front and corner side building lines of the principal building to the front and corner side lot lines. A yard that abuts an alley is not an effective street yard.
      2.   The effective interior side yard extends from the closest point of the side of the principal building to the interior side lot.
      3.   The effective rear yard extends from the closest point of the rear of the principal building to the rear lot line.
Figure 16.60-2:  Effective Yards
 
   E.   Contiguous Lots or Parcels. In the event that the construction of a building or the establishment of a use requires multiple lots or parcels in order to meet the lot area, setback, or lot or parcel dimensional requirements of this Ordinance for the building or use, the lots or parcels shall be deed restricted prior to construction of the building or establishment of the use using County approved deed restriction language.
   F.   Building Height.
      1.   Principal Building Height.
         a.   Principal building height is measured as the vertical distance from the average ground elevation to:
            (1)   The highest point of the coping of a flat roof.
            (2)   The deck line of a mansard roof.
            (3)   The mean height level that is located midway between the eaves and ridge for gable, hip, or gambrel roofs.
         b.   Chimneys, architectural towers, spires, elevator penthouses, cooling towers, and similar appurtenances are not included in calculating building heights.
         c.   See § 16.56.050A. (Accessory Structures – General Regulations) for accessory structure height limits.
Figure 16.60-3:  Principal Building Height Measurement
 
      2.   Exempt Structures. The following structures or their appurtenances are exempt from the height limitations within the zoning districts, unless limited by height restriction imposed by an airport authority or similar agency operating an airport, or other state or federal exemptions:
         a.   Agricultural buildings.
         b.   Bell towers.
         c.   Bulk storage towers and silos.
         d.   Cooling towers.
         e.   Flagpoles not used for advertising.
         f.   Gravity feed apparatus.
         g.   Public utility poles, towers, wires, and other apparatus.
         h.   Smokestacks.
         i.   Towers and antennas, subject to the conditions of §§ 16.56.030RR. and 16.56.030SS.
         j.   Water storage towers, tanks, and standpipes.
         k.   Wind energy systems, subject to the conditions of § 16.56.030TT.
         l.   Attached accessory structures, subject to the conditions of § 16.60.030.
(Ord. O-201410-10-035, passed 10-14-2014; Ord. O-201601-ZBA-006, passed 1-19-2016; Ord. O-201603-ZBA-010, passed 3-17-2016, § 15.1; Ord. O-201803-ZBA-10-08, passed 3-19-2018; Ord. O-201808-10-033, passed 8-21-2018; Ord. O-201911-ZBA-057, passed 11-19-2019)