For the purpose of prescribing regulations for erecting, construction, enlargement, alteration, repair, improving, removal, conversion, demolition, occupancy, equipment use, height, and area of buildings and structures, the following construction codes subject to the modifications set forth in this chapter, are hereby adopted. The California Building Code, 2025 Edition, based on the 2024 International Building Code as published by the International Code Council, including Chapter 1, Division II. The California Residential Code, 2025 Edition, based on the 2024 International Residential Codes published by the International Code Council, including Chapter 1, Division II; including Appendix AX Swimming Pool Safety Act. The 2025 California Fire Code based on the 2024 International Fire Code. The 2025 California Green Building Standards Code. The 2025 Existing Building Code, based on the 2024 International Existing Building Code. The 2025 California Wildland-Urban Interface Code, based on the 2024 International Wildland- Urban Interface Code. The 2021 International Swimming Pool & Spa Code. The California Plumbing Code, 2025 Edition, based on the 2024 Uniform Plumbing Code as published by the International Association of Plumbing and Mechanical Officials. The California Mechanical Code, 2025 Edition, based on the 2024 Uniform Mechanical Code as published by the International Association of Plumbing and Mechanical Officials. The California Electrical Code, 2025 Edition, based on the 2023 National Electrical Code as published by the National Fire Protection Association. The California Energy Code, 2025 Edition, based on the 2024 International Energy Conservation Code. The International Property Maintenance Code, 2024 Edition, as published by the International Code Council. The Uniform Code for the Abatement of Dangerous Buildings, 2021 Edition, as published by the International Code Council. For the purpose of prescribing regulations for grading and excavation, the Orange County Grading and Excavation Code will be hereby adopted, in addition, to Appendix "J" of the 2025 California Building Code and the more restrictive provisions of the two will prevail. The provisions of these Construction Codes as amended by this chapter shall constitute the Building Regulations of the City of Costa Mesa. Where the California Code of Regulations and State Building Standards Code of Regulations differ from any sections of the Construction Codes, State regulations shall prevail over the Construction Codes.
One copy of all the above codes and standards therefore are on file in the office of the building official pursuant to Health and Safety Code section 18942(d)(1) and are made available for public inspection.
Notwithstanding the provisions of the above-referenced construction codes, all fees for services provided pursuant to the construction codes shall not take effect until a resolution for such fees is adopted by the city council pursuant to California Government Code sections 66016 and 66020.
(Code 1960, § 8100; Ord. No. 62-4, 3-5-62; Ord. No. 65-20, 7-19-65; Ord. No. 68-44, 12-2-68; Ord. No. 68-45, 12-2-68; Ord. No. 71-14, § 2, 6-21-71; Ord. No. 75-3, § 2, 1-4-75; Ord. No. 82-13, § 2(1), 9-7-82; Ord. No. 87-22, § 2(1), 11-2-87; Ord. No. 92-22, § 1, 12-21-92; Ord. No. 95-22, § 2, 1-2-96; Ord. No. 99-6, § 1, 6-7-99; Ord. No. 07-18, § 1, 10-16-07; Ord. No. 10-10, § 1, 9-21-10; Ord. No. 13-06, § 1, 11-19-13; Ord. No. 16-14, § 1, 12-6-16; Ord. No. 19-18, § 1, 11-19-19; Ord. No. 22-07, § 1, 11-2-22; Ord. 2025-08, 11/18/2025)
The following amendments to the California Building Code shall apply in the city:
(a) 
Administration. Division II of Chapter 1, entitled "Scope and Administration", is applicable in the city.
(b) 
Revision. Insert City of Costa Mesa into the text as the name of jurisdiction in Section 101.1.
(c) 
Section 101.4 is deleted in its entirety (including sections 101.4.1, 101.4.2, 101.4.3, 101.4.4, 101.4.5, 101.4.6 and 101.4.7), and replaced with the following:
101.4. Referenced Codes. The California Codes listed in Section 5-1 of this Ordinance shall be considered part of the requirements of this code to the extent of each such reference.
(d) 
Section 105.2 is revised by amending exception 2, 9, and adding 14 as follows:
2. 
Wood, Steel, Vinyl, or Iron fences not over 6 feet in height. Stucco, concrete, and masonry brick fences not over 3 feet high.
9. 
Prefabricated swimming pools accessory to a Group R-3 occupancy that are less than 18 inches (457.2 mm) deep, do not exceed 5,000 gallons (18,927.059 L) and are installed entirely above ground.
14. 
Decks not exceeding 200 square feet (18.58 m2) in area, that are not more than 30 inches (762 mm) above grade at any point, are not attached to a dwelling and do not serve the exit door required by Section R311.2.
(e) 
Board of Appeals. Section 113.3 is amended to provide as follows:
Board of Appeals, when used in the Building Standards Codes shall mean the City Planning Commission. The Board of Appeals is hereby established for each of the Building Standards Codes. Depending on the subject of the appeal, specialized expertise may be solicited for the purpose of providing input to the Appeals Board.
(f) 
Table 1505.1 is amended, by the deletion of Table 1505.1 and the addition of a new Table 1505.1 thereto, to read as follows:
TABLE 1505.1a
MINIMUM ROOF COVERING CLASSIFICATIONS
TYPES OF CONSTRUCTION
IA
IB
IIA
IIB
IIIA
IIIB
IV
VA
VB
B
B
B
B
B
B
B
B
B
For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929 m2.
a.
Unless otherwise required in accordance with Part 7, California Wildland Urban Interface Code (WUI)
(g) 
Section 1505.1.2 is amended to read as follows:
1505.1.2 Roof coverings within all other areas other than Fire Hazard Severity Zones or Wildland - Urban Interface (WUI). The entire roof covering of every existing structure where more than fifty 50 percent of the total roof area is replaced within any one-year period, the entire roof covering of every new structure, and any roof covering applied in the alteration, repair or replacement of the roof of every existing structure, shall be a fire-retardant roof covering that is at least Class B.
(h) 
Section 1505.4 is amended, by the deletion of the entire section.
(i) 
Section 1505.5 is amended, by the deletion of the entire section.
(j) 
Section 1807.1.6 is amended to read as follows:
1807.1.6 Prescriptive design of concrete and masonry foundation walls. Concrete and masonry foundation walls that are laterally supported at the top and bottom shall be permitted to be designed and constructed in accordance with this section. Prescriptive design of foundation walls shall not be used for structures assigned to Seismic Design Category D, E or F.
(Ord. No. 07-18, § 2, 10-16-07; Ord. No. 10-10, § 2, 9-21-10; Ord. No. 11-4, § 1, 3-15-11; Ord. No. 13-06, § 2, 11-19-13; Ord. No. 16-14, § 2, 12-6-16; Ord. No. 19-18, § 2, 11-19-19; Ord. No. 22-07, § 1, 11-2-22; Ord. 2025-08, 11/18/2025)
Pursuant to the Assembly Bill 130 (AB 130), effective from October 1, 2025, through June 1, 2031, no new amendments are proposed for to the California Residential Code. The existing amendments shall remain in effect as currently adopted.
(a) 
Amend item number 2" in section R105.2, Work exempt from permit, as follows:
2. 
Wood, Steel, Vinyl, or Iron fences not over 6 feet in height. Stucco, concrete, and masonry brick fences not over 3 feet high.
(b) 
Table R301.2, is revised to read as follows:
TABLE R301.2
CLIMATIC AND GEOGRAPHIC DESIGN CRITERIA
Ground Snow Loado
WIND DESIGN
Seismic Design Categoryf
SUBJECT TO DAMAGE FROM
Ice Barrier Under-layment Requiredh
Flood Hazardsg
Air Freeze Indexi
Mean Annual Tempj
Speedd
(mph)
Topographic Effectsk
Special Wind Regionl
Windbourne Debris Zonem
Weatheringa
Frost Line Depthb
Termitec
Zero
95
No
No
No
D2 or E
Negligible
No
Very Heavy
No
No
Zero
60
MANUAL J DESIGN CRITERIAn
Elevation
Altitude Correction Factore
Coincident Wet Bulb
Indoor Winter Design Relative Humidity
Indoor Winter Design Dry-Bulb Temperature
Outdoor Winter Design Dry-Bulb Temperature
Heating Temperature Difference
98
1.0
69
—
70
43
27
Latitude
Daily Range
Summer Design Grains
Indoor Summer Design Relative Humidity
Indoor Summer Design Dry-Bulb Temperature
Outdoor Summer Design Dry-Bulb Temperature
Cooling Temperature Difference
34
Low
23
50% RH
75
85
10
For SI: 1 pound per square foot = 0.0479 kPa, 1 mile per hour = 0.447 m/s.
a.
Where weathering requires a higher strength concrete or grade of masonry than necessary to satisfy the structural requirements of this code, the frost line depth strength required for weathering shall govern. The weathering column shall be filled in with the weathering Index, "negligible," "moderate" or "severe" for concrete as determined from Figure R301.2(1). The grade of masonry units shall be determined from ASTM C34, ASTM C55, ASTM C62, ASTM C73, ASTM C90, ASTM C129, ASTM C145, ASTM C216 or ASTM C652.
b.
Where the frost line depth requires deeper footings than indicated in Figure R403.1(1), the frost line depth strength required for weathering shall govern. The jurisdiction shall fill in the frost line depth column with the minimum depth of footing below finish grade.
c.
The jurisdiction shall fill in this part of the table to indicate the need for protection depending on whether there has been a history of local subterranean termite damage.
d.
The jurisdiction shall fill in this part of the table with the wind speed from the ultimate design wind speeds map [Figure R301.2(2)]. Wind exposure category shall be determined on a site-specific basis in accordance with Section R301.2.1.4.
e.
The jurisdiction shall fill in this section of the table to establish the design criteria using Table 10A from ACCA Manual J or established criteria determined by the jurisdiction.
f.
The jurisdiction shall fill in this part of the table with the seismic design category determined from Section R301.2.2.1.
g.
The jurisdiction shall fill in this part of the table with: the date of the jurisdiction's entry into the National Flood Insurance Program (date of adoption of the first code or ordinance for management of flood hazard areas); and the title and date of the currently effective Flood Insurance Study or other flood hazard study and maps adopted by the authority having jurisdiction, as amended.
h.
In accordance with Sections R905.1.2, R905.4.3.1, R905.5.3,1, R905.6.3.1, R905.7.3.1, and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part at the table with "YES." Otherwise, the jurisdiction shall fill in this part of the table with "NO."
i.
The jurisdiction shall fill in this part of the table with the 100-year return period air freezing index (BF-days) from Figure R403.3(2) or from the 100-year (99 percent) value on the National Climatic Data Center data table "Air Freezing Index-USA Method (Base 32°F)."
j.
The jurisdiction shall fill in this part of the table with the mean annual temperature from the National Climatic Data Center data table "Air Freezing Index-USA Method (Base 32°F)."
k.
In accordance with Section R301.2.1.5, where there is local historical data documenting structural damage to buildings due to topographic wind speed-up effects, the jurisdiction shall fill in this part of the table with "YES." Otherwise, the jurisdiction shall indicate "NO" in this part of the table.
l.
In accordance with Figure R301.2(2), where there is local historical data documenting unusual wind conditions, the jurisdiction shall fill in this part of the table with "YES" and identify any specific requirements, Otherwise, the jurisdiction shall indicate "NO" in this part of the table.
m.
In accordance with Section R301.2.1.2 the jurisdiction shall indicate the wind- borne debris wind zone(s). Otherwise, the jurisdiction shall indicate "NO" In this part of the table.
n.
The jurisdiction shall fill in these sections of the table to establish the design criteria using Table 1a or 1b from ACCA Manual J or established criteria determined by the jurisdiction.
o.
The jurisdiction shall fill in this section of the allowable stress design table using the Ground Snow Loads in Figure R301.2(3).
(c) 
Section R902.1 is amended by revising it to allow only class A or B roofs as follows:
R902.1 Roofing covering materials. Roofs shall be covered with materials as set forth in Sections R904 and R905. A minimum Class A or B roofing shall be installed in areas designated by this section. Class A or B roofing required by this section to be listed shall be tested in accordance with UL 790 or ASTM E 108.
Exceptions:
1. 
Class A roof assemblies include those with coverings of brick, masonry and exposed concrete roof deck.
2. 
Class A roof assemblies also include ferrous or copper shingles or sheets, metal sheets and shingles, clay or concrete roof tile, or slate installed on noncombustible decks.
3. 
Class A roof assemblies include minimum 16 oz/ft2 copper sheets installed over combustible decks.
(d) 
Section R902.1.2 is amended by revising it to require a minimum Class B as follows:
R902.1.2 Roof coverings within all other areas. The entire roof covering of every existing structure where more than 50 percent of the total roof area is replaced within any one-year period, the entire roof covering of every new structure, and any roof covering applied in the alteration, repair or replacement of the roof of every existing structure, shall be a fire-retardant roof covering that is at least class B.
(e) 
Section R902.2, first paragraph is amended by revising it to allow only class A or B treated wood roofs as follows:
R902.2 Fire-retardant-treated shingles and shakes. Fire-retardant-treated wood shakes and shingles are wood shakes and shingles complying with UBC Standard 15-3 or 15-4 which are impregnated by the full-cell vacuum-pressure process with fire- retardant chemicals, and which have been qualified by UBC Standard 15-2 for use on Class A or B roofs.
Fire-retardant-treated wood shakes and shingles shall comply with ICC-ES EG107 and with the weathering requirements contained in Health and Safety Code section 13132.7(j). Each bundle shall bear labels from an ICBO accredited quality control agency identifying their roof-covering classification and indicating their compliance with ICC-ES EG107 and with the weathering requirements contained in Health and Safety Code section 13132.7(j).
Health and Safety Code section 13132.7(j) No wood roof covering materials shall be sold or applied in this state unless both of the following conditions are met:
1. 
The materials have been approved and listed by the State Fire Marshal as complying with the requirements of this section.
2. 
The materials have passed at least five years of the 10-year natural weathering test. The 10-year natural weathering test required by this subdivision shall be conducted in accordance with Standard 15-2 of the 1994 Edition of the Uniform Building Code at a testing facility recognized by the State Fire Marshal.
(Ord. No. 10-10, § 3, 9-21-10; Ord. No. 11-4, § 1, 3-15-11; Ord. No. 13-06, § 3, 11-19-13; Ord. No. 16-14, § 3, 12-6-16; Ord. No. 17-03, § 2, 2-7-17; Ord. No. 19-18, § 3, 11-19-19; Ord. No. 22-07, § 1, 2022; Ord. 2025-08, 11/18/2025)
Article 8 of Title 7, Division 1 of the Codified Ordinances of the County of Orange, including the Grading Manual, is adopted in its entirety, except that section 7-1-805(i) and 7-1-805(l) are modified as follows:
Section 7-1-805(i). A fill less than one (1) foot in depth which: (1) is placed on a natural grade with a slope less steep than five horizontal to one vertical (5:1); (2) does not exceed twenty (20) cubic yards on any one lot; and (3) does not obstruct a drainage course. This does not exempt the project proponent from submitting a compaction report, to the Building Official, for review and approval, on the fill placed.
Section 7-1-805(I). A fill less than three (3) feet in depth for a landscape planter, which does not exceed twenty (20) cubic yards on any one lot and does not obstruct a drainage course.
(Ord. No. 19-18, § 5.5, 11-19-19; Ord. 2025-08, 11/18/2025)
(a) 
Enforcement of the construction codes adopted by section 5-1 shall be the responsibility of the building official. All references to the building official or director of building and safety shall deem to mean the building official responsible for the division of building and code enforcement.
(b) 
The provisions of title shall apply to and affect all of the territory of the City of Costa Mesa, except work located primarily in a public way, public utility towers and poles, mechanical equipment not specifically regulated by this title, hydraulic flood control structures, facilities for the production, generation, storage or transmission of water or electrical energy by a local agency, and the buildings or structures of administration and instruction of public schools when acting under the state contract act, except as otherwise provided in this title.
(c) 
Additions, alterations, repairs and changes of use or occupancy of all buildings and structures shall comply with the provisions for new buildings and structures, except as otherwise provided in this title.
(d) 
Where, in any specific case, different sections of the construction codes specify different materials, methods of construction or other requirements, the most restrictive shall govern.
(e) 
Pursuant to section 1-33.1 of this Code, the development services director and his deputies are designated as enforcement officials with authority to issue citations for violations of this Code either as a misdemeanor or infraction.
(Ord. No. 92-22, § 3, 12-21-92; Ord. No. 95-22, § 3, 1-2-96; Ord. No. 98-19, § 1, 7-6-98; Ord. No. 07-18, § 3, 10-16-07)
(a) 
Notwithstanding the provisions of sections 1-33(d) and 5-1, all appeals from determinations and orders by the building official and/or the fire marshal shall be to the access, building, fire and housing board of appeals (the "board"). The board may adopt reasonable rules and regulations for conducting its investigations and shall render its decisions and findings on contested matters in writing to the building official or the fire marshal, as applicable, with a duplicate copy thereof to any appellant or contestant affected by a decision or findings of the board.
(b) 
The above-referenced appeals shall be filed with the building official on application forms established by the appeals board and consistent with the Construction Codes adopted in section 5-1. An appeal application fee shall be paid to process the appeal as set by resolution of city council. Notice of the appeal and appeal hearing shall comply with the Construction Codes adopted in section 5-1.
(c) 
The decision by the board shall be final on the date made and not subject to further appeal to city council.
(d) 
The decision by the board shall be final on the date made and the provisions of California Code of Civil Procedure section 1094.6 shall apply to such decision.
(e) 
Where a notice and order of the building official or fire marshal or decision of the board becomes final and a violation of this title has been determined to exist, the city attorney is hereby authorized to commence civil or criminal proceedings to abate the violation of the provisions of this title. A violation of any provision of this title shall constitute a public nuisance and costs for abatement, including attorney's fees and court costs, shall be subject to reimbursement from the property owner to the city pursuant to the construction codes adopted in section 5-1.
(Ord. No. 95-11, § 1, 8-7-95; Ord. No. 04-14, § 1, 12-6-04; Ord. No. 07-18, § 3, 10-16-07; Ord. No. 10-10, § 4a., b., 9-21-10)
The development services director or his or her designee shall collect fees for permits and services specified in this title. Where the development services director or his designee finds that the fees prescribed in this title do cover the cost of providing the service which is the subject of the fee, the development services director or his designee may charge a supplemental fee for the unpaid cost of the services provided.
(Ord. No. 92-22, § 5, 12-21-92)
In addition to the regulations adopted in section 5-1, city council finds that the public health, safety and welfare is protected by prescribing a uniform building standard for the construction and rehabilitation of alleys located on private property and used for ingress and egress by the public. All public access alleys on private property constructed or rehabilitated under a permit issued after the effective date of this section shall comply with city standard no. 118, typical section for alley and "V" gutter, established by the public services department and attached [to Ordinance No. 95-23] as exhibit 1 and incorporated herein by this reference. The building standard provided in this section shall apply to all public access alleys on private property where the cost of construction or rehabilitation work exceeds 50% of the total replacement cost of the alley subject to a permit issued under this title.
(Ord. No. 95-23, § 1, 1-2-96)
(a) 
It is unlawful for any person, firm, corporation, or other entity, to erect, construct, enlarge, alter, repair, move, improve, remove, convert, demolish, equip, use, occupy or maintain any building, structure or real property in the city, or cause the same to be done, contrary to or in violation of any of the provisions of this Code.
(b) 
Any person, firm or corporation violating any of the provisions of this title shall be deemed guilty of a misdemeanor. Any such person shall be deemed guilty of a separate offense for each and every day or portion thereof during which any violation of this title is committed, continued or permitted.
(c) 
Notice and order. When the development services director or his designee has inspected or caused to be inspected a building and has found and determined that such building is a substandard building, the development services director or his designee shall commence proceedings to cause the repair, rehabilitation, vacation or demolition of the building. The development services director or his designee shall issue a notice and order directed to the record owner of the building. The notice and order shall contain:
(1) 
The street address and a legal description for identification of the premises upon which the building is located.
(2) 
A statement that the development services director or his designee has found the building to be substandard with a brief and concise description of the conditions found to render the building dangerous under the provisions of section 202 of this Code.
(3) 
A statement of the action required to be taken determined by the development services director.
a. 
If the development services director or his designee has determined that the building or structure must be repaired, the order shall require that all required permits be secured therefor and the work physically commenced within such time (not to exceed 60 days from the date of the order) and completed within such time as the development services director or his designee shall determine is reasonable under all of the circumstances.
b. 
If the development services director or his designee has determined that the building or structure must be vacated, the order shall require that the building or structure shall be vacated within a certain time from the date of the order as determined by the development services director or his designee to be reasonable.
c. 
If the development services director or his designee has determined that the building or structure must be demolished, the order shall require that the building be vacated within such time as the development services director or his designee shall determine reasonable (not to exceed 60 days from the date of the order), that all required permits be secured therefor within 60 days from the date of the order and that the demolition be completed within such time as the development services director or his designee shall determine is reasonable.
(4) 
Statements advising that if any required repair or demolition work (without vacation also being required) is not commenced within the time specified, the development services director or his designee:
a. 
Will order the building vacated and posted to prevent further occupancy until the work is completed, and
b. 
May proceed to cause the work to be done and charge the costs thereof against the property or its owner.
(5) 
Statements advising:
a. 
That any person having any record title or legal interest in the building may appeal from the notice and order or any action of the director of development services or his designee to the appeals board, provided that the appeal is made in writing as provided in this Code, and filed with the director of development services or his designee within 30 days from the date of service of such notice and order, and
b. 
That failure to appeal will constitute a waiver of all right to an administrative hearing and determination of the matter.
(d) 
Service of notice and order. The notice and order, and any amended or supplemental notice and order, shall be served upon the record owner, and posted on the property; and one copy thereof shall be served on each of the following if known to the director of development services or his designee or disclosed from official public records: The holder or any mortgage or deed of trust or other lien or encumbrance of record; the owner or holder of any lease of record; and the holder of any other estate or legal interest of record in or to the building or the land on which it is located. The failure of the director of development services or his designee to serve any person required herein to be served shall not invalidate any proceedings hereunder as to any other person duly served or relieve any such person from any duty or obligation imposed by the provisions of this action.
(e) 
Method of service. Service of the notice and order shall be made upon all persons entitled thereto either personally or by mailing a copy of such notice and order by certified mail, postage prepaid, return receipt requested, to each such person at their address as it appears on the last equalized assessment roll of the county or as known to the director of development services. If no address of any such person so appears or is known to the director of development services, then a copy of the notice and order shall be so mailed, addressed to such person, at the address of the building involved in the proceedings. The failure of any such person to receive such notice shall not affect the validity of any proceedings taken under this section. Service by certified mail in the manner herein provided shall be effective on the date of mailing.
(f) 
Proof of service. Proof of service of the notice and order shall be certified to at the time of service by a written declaration under penalty of perjury executed by the person effecting service, declaring the time, date and manner in which service was made. The declaration, together with any receipt card returned in acknowledgment of receipt by certified mail, shall be affixed to the copy of the notice and order retained by the director of development services.
(Ord. No. 92-22, § 6, 12-21-92)
The full value of any building, structure or alteration shall be given when making application for a permit required by this title. The fact that the owner expects to do the labor himself and to use materials which he already has on the premises shall not detract from the value of the materials or labor. The value of materials and labor is deemed to be definite and ascertainable regardless of by whom furnished, and such value shall be included in the estimated cost when applying for a permit.
(Code 1960, § 8102)
The director of development services or his designee is authorized to issue permits for buildings or structures under the provisions of this title whenever the applicant has complied with all the requirements hereof.
(Ord. No. 92-22, § 7, 12-21-92; Ord. No. 98-19, § 2, 7-6-98)
Refund of any fee paid by the applicant pursuant to this title may be made as provided in the construction codes adopted in section 5-1 or by established policy.
(Code 1960, § 8104; Ord. No. 66-49, 12-19-66; Ord. No. 67-16, 6-27-67; Ord. No. 82-13, § 2(8), 9-7-82; Ord. No. 87-22, § 2(9), 11-2-87; Ord. No. 92-22, § 9, 12-21-92; Ord. No. 95-22, § 4, 1-2-96; Ord. No. 99-6, § 2, 6-7-99; Ord. No. 07-18, § 3, 10-16-07)