Chapter 16.67
DAYLIGHT PLANES

Sections:

16.67.010    Daylight planes in R-E, R-E-S and R-2 zoning districts.

16.67.020    Daylight planes in R-1-S and R-1-U zoning districts.

*    Prior ordinance history: Ords. 791 and 801.

16.67.010 Daylight planes in R-E, R-E-S and R-2 zoning districts.

Daylight planes for the main dwelling unit are established for each lot as follows:

(1)    Daylight Plane. A daylight plane shall begin at a horizontal line at a certain distance directly above each side setback line of each lot and shall slope inwards at a forty-five (45) degree angle. The distance between the side setback line and the horizontal line directly above it shall be nineteen (19) feet, six (6) inches above the grade of the side setback line. For an addition to an existing structure, such distance shall be the higher of:

(A)    Nineteen (19) feet, six (6) inches above the grade of the side setback line; or

(B)    Eighteen (18) feet above the underside of the actual first floor, measured at the side wall, or twenty (20) feet, six (6) inches above the grade of the sidewall, whichever is lower.

As used in this section, an "addition to an existing structure" does not include construction over a new foundation or construction cantilevered beyond a new or existing foundation, "grade of the side wall" means the average grade of the highest and lowest points of the natural grade of the portion of the lot covered by the side wall, and "grade of the side setback line" means the average grade of the highest and lowest points of the natural grade of the portion of the lot directly below the side setback line. No portion of the structure shall intrude beyond the daylight plane except for dormers and gables as provided in subsection (2) of this section and chimneys, vents, flues and solar collectors.

(2)    Gable and Dormer Intrusions. Gables and dormers may intrude into the daylight plane of a lot that is ten thousand (10,000) square feet or less. The permitted intrusion shall decrease on an even gradient from ten feet (10’) in the case of a five foot (5’) required side setback to no permitted intrusion in the case of an eight foot (8’) required side setback. Thus the permitted intrusion will be six feet (6’), eight inches (8") in the case of a six foot (6’) required side setback, five feet (5’) in the case of a six and one-half foot (6.5") required side setback, and three feet (3’), four inches (4") in the case of a seven foot (7’) required side setback. Calculations of the permitted intrusion shall include fractional computations when necessary to maintain the even gradient. Gables and dormers may intrude into the daylight plane on one (1) side of a lot only. The gable or dormer must not extend beyond a triangle described as follows:

(A)    The base of the triangle is the line formed by the intersection of the building wall with the daylight plane;

(B)    The aggregate length of the bases of all triangles intruding into a daylight plane shall not exceed thirty feet (30’); and

(C)    The triangle must be entirely within the maximum building height. (Ord. 1006 § 18 (part), 2014; Ord. 938 § 8 (part), 2005).

16.67.020 Daylight planes in R-1-S and R-1-U zoning districts.

Daylight planes for the main dwelling unit are established for each lot as follows:

(1)    Daylight Plane. A daylight plane shall begin at a horizontal line at a certain distance directly above each side setback line of each lot and shall slope inwards at a forty-five (45) degree angle. The distance between the side setback line and the horizontal line directly above it shall be as follows:

(A)    Single-story development: twelve (12) feet, six (6) inches above the grade of the side setback line;

(B)    Development of two or more stories: nineteen (19) feet, six (6) inches above the grade of the side setback line. For an addition to an existing structure, such distance shall be the higher of:

(i)    Nineteen (19) feet, six (6) inches above the grade of the side setback line; or

(ii)    Eighteen (18) feet above the underside of the actual first floor, measured at the side wall, or twenty (20) feet, six (6) inches above the grade of the side wall, whichever is lower.

As used in this section, an "addition to an existing structure" does not include construction over a new foundation or construction cantilevered beyond a new or existing foundation, "grade of the side wall" means the average grade of the highest and lowest points of the natural grade of the portion of the lot covered by the side wall, and "grade of the side setback line" means the average grade of the highest and lowest points of the natural grade of the portion of the lot directly below the side setback line. No portion of the structure shall intrude beyond the daylight plane except for dormers and gables as provided in subsection (2) of this section and chimneys, vents, flues and solar collectors.

(2)    Gable and Dormer Intrusions. Gables and dormers may intrude into the daylight plane of a lot as follows:

(A)    Single-story development: no permitted gable or dormer intrusions.

(B)    Development of two (2) or more stories: gables and dormers may intrude into the daylight plane of a lot that is ten thousand (10,000) square feet or less. The permitted intrusion shall decrease on an even gradient from ten feet (10’) in the case of a five foot (5’) required side setback to no permitted intrusion in the case of an eight foot (8’) required side setback. Thus the permitted intrusion will be six feet (6’), eight inches (8") in the case of a six foot (6’) required side setback, five feet (5’) in the case of a six and one-half foot (6.5’) required side setback, and three feet (3’), four inches (4") in the case of a seven foot (7’) required side setback. Calculations of the permitted intrusion shall include fractional computations when necessary to maintain the even gradient. Gables and dormers may intrude into the daylight plane on one (1) side of a lot only. The gable or dormer must not extend beyond a triangle described as follows:

(i)    The base of the triangle is the line formed by the intersection of the building wall with the daylight plane;

(ii)    The aggregate length of the bases of all triangles intruding into a daylight plane shall not exceed thirty feet (30’); and

(iii)    The triangle must be entirely within the maximum building height. (Ord. 1006 § 18 (part), 2014; Ord. 938 § 8 (part), 2005).