§512.0604 Maintenance of Defensible Space
(a) Local Amendment. Section 604.1, General, is amended to read as follows:
A responsible person shall manage vegetation and fuels to reduce the severity of potential exterior wildfire exposure to structures and to reduce the risk of fire spreading to structures, as required by applicable laws and regulations.
(b) Local Amendment. Section 604.2, Application, is amended to read as follows:
Structures located within Wildland-Urban Interface Areas shall maintain the required vegetation and fuel management.
(c) Local Amendment. Section 604.3, Requirements, is amended to read as follows:
A responsible person shall maintain vegetation and fuel around all structures in accordance with the following laws and regulations;
(1) Public Resources Code section 4291;
(2) California Code of Regulations, Title 14, Division 1.5, Chapter 7, Subchapter 3, Article 3, section 1299.03;
(3) California Government Code section 51182; and
(4) California Code of Regulations, Title 19, Division 1, Chapter 7, Subchapter 1, Section 3.07.
(d) Local Addition. Section 604.3.1, Defensible Space Fuel Modification Zones, is added as follows:
(1) A responsible person shall at all times maintain a defensible space zone(s) around a structure within a Wildland-Urban Interface Area by removing, clearing, or modifying combustible vegetation and other flammable materials from areas within 100 feet (30 480 mm) from all portions of any structure. When a structure is setback less than 100 feet (30 480 mm) from the property line, a defensible space fuel modification zone shall be maintained in the area between the structure and the property line.
(2) Distances may be increased by the Fire Code Official because of a site-specific analysis, based on local conditions or, when required, based on a fire protection plan.
(e) Local Addition. Section 604.3.2, Zone 0 Requirements, is added as follows:
Zone 0 is the area immediately adjacent to the exterior wall surface or patio, deck, or attachment to structures extending 5 feet (1524 mm) on a horizontal plane. Zone 0 requirements shall apply to all new structures applying for a building permit on or after the effective date of this Ordinance, and shall apply to existing structures one year after the Ordinance effective date. A compliance plan may be established to allow sufficient time for structures to fully comply with these regulations. The requirements within Zone 0 are as follows:
(1) No landscape materials that are likely to be ignited by embers are permitted within Zone 0. This includes ornamental or native plants, shrubs, fallen leaves and tree needles, weeds, and combustible mulches including bark and woodchips; and
(2) No items that are likely to be ignited by embers are permitted within Zone 0, including combustible boards, timbers, firewood, petroleum-based products, window boxes, and trellises. The responsible person shall keep the roof and rain gutters clear of leaves and needles. The area under decks, balconies, and stairs shall be kept free from vegetation and combustible items.
(f) Local Addition. Section 604.3.3, Zone 1 Requirements, is added as follows:
Zone 1 is the area immediately adjacent to Zone 0 and extends out in a horizontal plane from the structure. Zone 1 shall typically consist of pavement and permanently irrigated ornamental planting. All vegetation shall be well watered and well maintained by the responsible person. The requirements within Zone 1 are as follows:
(1) Vegetation within Zone 1 shall be primarily low-growing and less than 4 feet (1219 mm) in height except for trees; and
(2) The responsible person shall remove all dead and dying grass, plants, shrubs, trees, branches, leaves, weeds, and needles from Zone 1; and
(3) Trees within Zone 1 shall be located away from structures a minimum distance of 10 feet (3048 mm) as measured from the drip line of the tree at maturity to the roofline of a structure or chimney or stovepipe outlet; and
(4) Exposed firewood piles shall be relocated outside of Zone 1 unless they are completely enclosed in a fire-resistant material; and
(5) Zone 1 includes a transitional area adjacent to Zone 0 that protects the integrity of Zone 0 and is the area within 5 feet (1524 mm) of Zone 0 or to the property line, whichever is closer. Plants within this transitional zone shall not be greater than 2 feet (610 mm) in height.
(g) Local Addition. Section 604.3.4, Zone 2 Requirements, is added as follows:
Zone 2 is the area immediately adjacent to Zone 1 extending out in a horizontal plane from the structure. The responsible person shall comply with the requirements within Zone 2 as follows:
(1) Annual grasses and forbs shall be cut down to a maximum height of 4 inches (102 mm);
Exception: Grass may be maintained up to 18 inches (457 mm) in height on slopes where it is necessary to stabilize the soil and prevent erosion.
(2) Dead and dying woody surface fuels and aerial fuels shall be removed; except loose surface litter, normally consisting of fallen leaves or needles, twigs, bark, cones, and small branches, shall be permitted to a maximum depth of 3 inches (76 mm);
(3) All exposed wood piles must have a minimum of 10 feet (3048 mm) of clearance, down to bare mineral soil, in all directions;
(4) Horizontal and vertical spacing among shrubs and trees must follow the spacing guidelines in Table 604.3.6 (1);
(5) Approximately 50% of the plants over 24 inches (610 mm) in height shall be cut and cleared to a height of 6 inches (125 mm) to achieve the spacing required in Table 604.3.6 (1).
(6) Ground cover or shrubs that are less than 24 inches (610 mm) in height can be maintained in mosaic groupings of up to 400 square feet (37 square meters). Groupings shall be separated by a minimum of 10 feet (3048 mm); and
(7) All plants remaining after 50% are reduced in height shall be pruned to reduce fuel loading. Non-native plants shall be pruned before native plants are pruned.
(h) Local Addition. Section 604.3.5, Zone 3 Requirements, is added as follows:
Zone 3, when applicable, is considered a thinning zone and is any fuel modification zone greater than 100 feet (30 480 mm) from a structure. When provided, either by conditions of development or where required by the Fire Code Official, the amount of fuel reduction and removal shall take into consideration the type and density of fuels, aspects, topography, weather patterns, and fire history. Typical fuel reduction in Zone 3 is 50% thinning between 100 and 150 feet from the structure and 30% thinning between 150 and 200 feet from the structure.
(i) Local Addition. Section 604.3.6, Spacing and Separation Requirements, is added as follows:
The height, area and spacing of trees, shrubs, and other vegetation shall be in accordance with Tables 604.3.6 (1) and 604.3.6 (2).
Table 604.3.6 (1)
Plant Spacing Requirements
Trees | Minimum horizontal space from edge of one tree canopy to the edge of the next tree canopy
Slope | Spacing
0% to 20% | 10 feet
20% to 40% | 20 feet
Greater than 40% | 30 feet
Shrubs | Minimum horizontal space between edges of shrub
Slope | Spacing
0% to 20% | 2 times the height of the shrub
20% to 40% | 4 times the height of the shrub
Greater than 40% | 6 times the height of the shrub
Vertical Space | Minimum vertical space between top of shrub and bottom of lower tree branches: 3 times the height of the shrub
Table 604.3.6 (2) Vegetation Height and Area Requirements
Type of Vegetation | Zone | Maximum Height | Maximum Area /Diameter | % of Slope / Minimum Horizontal Spacing
Ground Cover | 1 & 2 | 12-inches | Not Applicable | Not Applicable
Mosaic Grouping of Ground Cover (GC) | 1 | 18-inches | Groupings shall not exceed 200 sq. ft. without minimum spacing to next grouping | Table 604.3.6 (1)
2 | 24-inches | Groupings shall not exceed 400 sq. ft. without minimum spacing to next grouping | Table 604.3.6 (1)
Single Shrub | 1 | 4 feet (2 feet within Zone 1 Transitional area) | 4-foot diameter | Table 604.3.6 (1)
2 | 6-feet | 4-foot diameter | Table 604.3.6 (1)
Grouping of shrubs | 1 | Not Allowed | Not Applicable | Not Applicable
2 | 4-feet | Groupings shall not exceed 100 sq. ft. without minimum spacing to next grouping | Table 604.3.6 (1)
Single Tree | 1 | Not Applicable | Tree canopy at full maturity not allowed within 10 feet of any structure | Table 604.3.6 (1)
2 | Not Applicable | Not Applicable | Table 604.3.6 (1)
(j) Local Addition. Section 604.3.7, Public Nuisance, is added as follows:
Any condition caused, maintained, or permitted to exist in violation of any provision of this code which constitutes a threat to public health, safety, and welfare may be deemed a public nuisance and may be abated by the City under the procedures set forth in San Diego Municipal Code, Chapter 1, Article 2, Divisions 06 and 07 and Chapter 5, Article 4, Division 02.
(k) Local Addition. Section 604.3.8, Vacant Lots, is added as follows:
(1) The responsible person shall remove trash, rubbish, debris, and other combustible materials, including weeds, which create a fire or safety hazard, from the property.
(2) The responsible person shall clear properties of one acre or less of weeds and other combustible vegetation or materials in their entirety.
(3) Properties larger than one acre:
(A) shall have a minimum of 30 feet (9144 mm) of clearance from the property lines that abut improved properties; and
(B) shall have a minimum of 100 feet (30 480 mm) of clearance from structures on adjacent properties.
(4) Clearance Requirements:
(A) Clearance of properties shall be accomplished by methods that will not disturb native soil or rootstock such as mowing or trimming. Cuttings may be mulched and left on top of the soil to a maximum depth of 3 inches (76 mm) or may be hauled to an approved landfill site; and
(B) Annual grasses and weeds shall not exceed a height of 4 inches (102 mm) or less; and
(C) The responsible person shall remove all dead or dry plants, shrubs, weeds, leaves, and pine needles; and
(D) Minimum vertical space between the top of shrubs and the bottom of lower tree branches shall be three times the height of the shrub (branches shall be no less than 6 feet above the ground); and
(E) Areas within 100 feet (30 480 mm) of a structure must be maintained in accordance with section 604.3.4.
(l) Local Addition. Section 604.3.9, Designated Evacuation Roadways, is added as follows:
Responsible person shall provide vegetation management along City-designated evacuation roadways. Vegetation management shall consist of clearing, modifying, or both clearing and modifying, 20 feet on each side of designated roadways. Vegetation management includes:
(1) maintaining grass to a maximum height of 4 inches;
(2) removing all vegetation that is not fire-smart;
(3) removing invasive species;
(4) removing all dead plants, shrubs, and weeds;
(5) removing dead or dry leaves and pine needles;
(6) trimming tree canopies and branches so that they do not extend over any portion of the roadway; and
(7) maintaining minimum vertical space between the top of shrubs and the bottom of lower tree branches to three times the height of the shrub. Branches shall be no less than six feet above the ground.
(m) Local Addition. Section 604.3.10, Prescribed Herbivory, is added as follows:
(1) Where specifically authorized by the Fire Code Official, goats may be used for brush management on privately owned land.
(2) At least 10 business days prior to using goats for brush management, the property owner shall apply to the Fire Rescue Department for a permit.
(“Maintenance of Defensible Space” added 1-29-2026 by O-22042 N.S.; effective 2-28-2026.)
