CMC · California Mechanical Code
What plans, calculations and documentation must be submitted?
For a homeowner: when you apply for a permit for process piping, you must submit plans, calculations and diagrams (at least one set); the local building department can require more sets, a licensed engineer/architect stamp, and a plan‑review fee — check the AHJ’s submittal checklist.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
The California Mechanical Code requires that plans, engineering calculations, diagrams, and other data be submitted with each application for a permit for process piping. The submission must be provided in one or more sets, and the Authority Having Jurisdiction (AHJ) may require that the documents be prepared and designed by a registered design professional. The AHJ may also assess a plan review fee when such documents are submitted for review. § 1403.0 and § 1403.1 are the controlling provisions.
Submit clear plans and engineering calculations (at least one set) with your process‑piping permit application; the AHJ may require additional sets, an RDP stamp, and a plan‑review fee. § 1403.1
Requirements in detail
Core items the CMC says must be submitted
- Plans, engineering calculations, diagrams, and other data with each permit application — required for process piping. § 1403.1
- Documents must be submitted in one or more sets; AHJ may require preparation/design by a registered design professional. § 1403.1
- If plans or other data are submitted for review, a plan review fee must be paid as provided in § 104.3.2. § 1403.1 directs to § 104.3.2 for fee procedures.
Note: The general construction document rules elsewhere in the code (e.g., § 104.3.1) add detail about how many sets, digital submittal, and when an RDP is required; those are commonly applied to process‑piping submissions.
Decision table — what to submit and where it comes from
| Decision / item | Typical value or trigger | Code Reference |
|---|---|---|
| Documents required | Plans, engineering calculations, diagrams, other data | § 1403.1 |
| Minimum number of sets (chapter 14) | One or more sets (chapter 14 language) | § 1403.1 |
| Typical minimum sets (general administration) | Two or more sets or digital where permitted (see general rules) | § 104.3.1 |
| Prepared/designed by RDP | When AHJ requires; AHJ is permitted to require RDP preparation/design | § 1403.1 |
| Plan review fee | Required when plans/data are submitted for review; fee per § 104.3.2 and local schedule | § 1403.1 directing § 104.3.2 |
| Content quality | Drawn to scale and clear enough to demonstrate code compliance (general requirement) | § 104.3.1 |
Practical content expectations (what reviewers look for)
The CMC text requires the categories of documents only; however, the AHJ will expect the submittal to be complete enough to verify compliance. Under the general construction‑document provisions the AHJ commonly enforces things like: documents drawn to scale, sufficient clarity to show the work, and (where statutorily required) preparation by a registered design professional. These expectations are implemented through § 1403.1 and the cross‑references to § 104.3.1 and § 104.3.2.
Exceptions & special cases
- The AHJ may waive submission of construction documents, calculations, or other data where the AHJ finds the nature of the work makes review unnecessary. This exception is stated in the general construction‑document section § 104.3.1 and may apply to process piping submittals.
- Chapter 14 specifically uses the phrase “one or more sets”, but the general rule elsewhere in the code requires two or more sets (or digital) for construction documents; follow the AHJ’s local submittal checklist to know which applies on your project. § 1403.1 and § 104.3.1.
Common mistakes
- Relying on the Chapter 14 text alone and ignoring the general submittal rules — e.g., submitting only one paper set where the AHJ requires two sets or digital files per § 104.3.1.
- Failing to pay the plan review fee when plans are submitted for review (AHJ enforces fees per § 104.3.2).
- Submitting drawings that aren’t drawn to scale or lack clarity to demonstrate compliance; the general document rules require clarity and scale.
- Assuming an RDP stamp is optional — the AHJ is explicitly permitted to require an RDP prepared design under § 1403.1. If local statutes require RDP signatures, the AHJ will enforce them.
Worked example — laboratory process piping (concrete numbers)
Scenario: Owner proposes new process piping in a university lab. The piping system will serve 12 outlets and requires a permit.
- What to prepare: Prepare plans, engineering calculations, and diagrams showing the piping layout, flow rates, materials, and connections. Submit these with the permit application per § 1403.1.
- How many sets: Chapter 14 allows one or more sets; however, the AHJ enforces the general requirement of two or more sets or digital submittal under § 104.3.1, so plan to submit two printed sets plus one digital set if the AHJ accepts electronic files.
- Who signs/seals: The AHJ may require that the plans/calculations be prepared and stamped by a registered design professional; confirm with the AHJ early. § 1403.1 permits the AHJ to require an RDP.
- Fees: Because plans are submitted for review, pay the plan review fee at submittal per § 104.3.2 (amount set by the jurisdiction). § 1403.1 points to the plan‑review fee procedure.
Result: Submit two printed sets + digital set, engineering calcs signed/sealed if required by AHJ, and pay the plan‑review fee at submittal. That satisfies the Chapter 14 requirement and the general construction document rules.
Related provisions
- § 1403.0 (Plans Required — heading for Chapter 14) — Chapter 14 context.
- § 1403.1 (General — plans, calculations, diagrams; AHJ may require RDP; plan review fee) — controlling text for process piping.
- § 1402.1 (Permits for process piping shall show the total number of outlets and such other information as required by the AHJ) — useful for what to include on the permit.
- § 104.3.1 (Construction documents — two or more sets, digital format where permitted; RDP where required; drawn to scale and clarity) — general submission requirements that apply to process‑piping submittals.
- § 104.3.2 (Plan review fees — fee due when plans/data submitted for review) — administrative fee procedure relevant to § 1403.1.
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 1.11.0. High relevance — show source text
SS/CC**|1|1R|2|3|4|5|6|6|6|6|6|6|6|6|6| |Adopting Agency
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amended (amended sections
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Chapter/Section||||||||||||||||||||||||| |Adopting Agency
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amended (amended sections
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amended (amended sections
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Chapter/Section|||||||||||||||||||||||||This state agency does not adopt sections identified with the following symbol: † The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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CHAPTER 14
PROCESS PIPING
1401.0 General.
1401.1 Applicability. Except as otherwise addressed in this code, this chapter shall govern the installation of process piping in or in conjunction with a building or structure located upon the premises.
1402.0 Permit.
1402.1 General. It shall be unlawful to install, alter, or repair or cause to be installed, altered, or repaired process material piping without first obtaining a permit.
Permits for process piping shall show the total number of outlets to be provided for on each system and such other information as required by the Authority Having Jurisdiction.
Fees for process piping permits are included in Table 104.5.
1403.0 Plans Required.
1403.1 General. Plans, engineering calculations, diagrams, and other data shall be submitted in one or more sets with each application for a permit. The Authority Having Jurisdiction shall be permitted to require plans, computations, and specifications to be prepared and designed by a registered design professional.
Where plans or other data are submitted for review, a plan review fee shall be paid, as provided in Section 104.3.2.
1404.0 Workmanship.
1404.1 General. Process piping shall not be strained or bent, nor shall tanks, vessels, vats, appliances, or cabinets be supported by or develop strain or stress on the piping.
CMC § 104.3.1. High relevance — show source text
DIVISION II SCOPE AND ADMINISTRATION
(2) Describe the land upon which the proposed work is to be done by legal description, street address, or similar description that will readily identify and definitely locate the proposed building or work.
(3) Indicate the use or occupancy for which the proposed work is intended.
(4) Be accompanied by construction documents and other data in accordance with Section 104.3.1.
(5) Be signed by the permittee or the permittee’s authorized agent. The Authority Having Jurisdiction shall be permitted to require evidence to indicate such authority.
(6) Give such other data and information in accordance with the Authority Having Jurisdiction.
104.3.1 Construction Documents. Construction documents, engineering calculations, diagrams, and other data shall be submitted in two or more sets, or in a digital format where permitted by the Authority Having Jurisdiction, with each application for a permit. The construction documents, computations, and specifications shall be prepared by, and the mechanical system designed by, a registered design professional. Construction documents shall be drawn to scale with clarity to identify that the intended work to be performed is in accordance with the code.
Exception: The Authority Having Jurisdiction shall be permitted to waive the submission of construction documents, calculations, or other data where the Authority Having Jurisdiction finds that the nature of the work applied for is such that reviewing of construction documents is not necessary to obtain compliance with the code.
104.3.2 Plan Review Fees. Where a plan or other data is required to be submitted in accordance with Section 104.3.1, a plan review fee shall be paid at the time of submitting construction documents for review.
The plan review fees for mechanical system work shall be determined and adopted by this jurisdiction.
The plan review fees specified in this subsection are separate fees from the permit fees specified in Section 104.5.
Where plans are incomplete or changed so as to require additional review, a fee shall be charged at the rate shown in Table 104.5.
104.3.3 Time Limitation of Application. Applications for which no permit is issued within 180 days following the date of application shall expire by limitation, plans and other data submitted for review thereafter, shall be returned to the applicant or destroyed by the Authority Having Jurisdiction. The Authority Having Jurisdiction shall be permitted to extend the time for action by the applicant for a period not to exceed 180 days upon request by the applicant showing that circumstances beyond the control of the applicant have prevented action from being taken. No application shall be extended more than once. In order to renew action on an application
after expiration, the applicant shall resubmit plans and pay a new plan review fee.
104.4 Permit Issuance. The application, construction documents, and other data filed by an applicant for a permit shall be reviewed by the Authority Having Jurisdiction. Such plans shall be permitted to be reviewed by other departments of this jurisdiction to verify compliance with applicable laws under their jurisdiction. Where the Authority Having Jurisdiction finds that the work described in an application for permit and the plans, specifications, and other data filed therewith are in accordance with the requirements of the code and other pertinent laws and ordinances and that the fees specified in Section 104.5 have been paid, the Authority Having Jurisdiction shall issue a permit therefore to the applicant.
CMC § 2.1. High relevance — show source text
In addition to the design calculations submitted under seal and signature, the following shall be included:
- Bridging design that differs from SJI 100 or SJI 200, such as cantilevered conditions and net uplift.
- Connection design for: 2.1. Connections that differ from SJI 100 or SJI 200, such as flush-framed or framed connections.
2.2. Field splices.
2.3. Joist headers.
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STEEL
2207 A .4 Steel joist drawings. Steel joist placement plans shall be provided to show the steel joist products as specified on the approved construction documents and are to be utilized for field installation in accordance with specific project requirements as stated in Section 2207 A .2. Steel joist placement plans shall include, at a minimum, the following:
- Listing of applicable loads as stated in Section 2207 A .2 and used in the design of the steel joists and joist girders as specified in the approved construction documents.
- Profiles for joist and joist girder configurations that differ from those defined by SJI 100 or SJI 200.
- Connection requirements for:
3.1. Joist supports. 3.2. Joist girder supports. 3.3. Field splices. 3.4. Bridging attachments. 4. Deflection criteria for joists and joist girder configurations that differ from those defined by SJI 100 or SJI 200. 5. Size, location and connections for bridging.
- Joist headers.
2207A.4.1 Design approval. [DSA-SS] Joist and joist girder design calculations and profiles with member sizes and connection details, and joist placement plans shall be provided to the enforcement agency and approved prior to joist fabrication, in accordance with the California Administrative Code (Title 24, Part 1). Joist and joist girder design calculations and profiles with member sizes and connection details shall bear the signature and stamp or seal of the registered engineer or licensed architect responsible for the joist design. Alterations to the approved joist and joist girder design calculations and profiles with member sizes and connection details, or to fabricated joists are subject to the approval of the enforcement agency.
2207 A .5 Certification. At completion of manufacture, the steel joist manufacturer shall submit a certificate of compliance to the owner or the owner’s authorized agent for submittal to the building official as specified in Section 1704.5 stating that work was performed in accordance with approved construction documents and with SJI 100 or SJI 200, as applicable.
2207A.6 Joist chord bracing. The chords of all joists shall be laterally supported at all points where the chords change direction.
SECTION 2208 A —STEEL DECK
2208 A .1 Steel decks. The design and construction of cold-formed steel floor and roof decks and composite slabs of concrete and steel deck shall be in accordance with SDI SD. The design of cold-formed steel diaphragms shall be in accordance with additional provisions of AISI S310, as applicable. The base material thickness of steel deck shall not be less than 0.0359 inch (0.9 mm) (20 gage).
CMC § 104.3.1. High relevance — show source text
(3) Indicate the use or occupancy for which the proposed work is intended.
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DIVISION II SCOPE AND ADMINISTRATION
(4) Be accompanied by construction documents in accordance with Section 104.3.1.
(5) Be signed by the permittee or the permittee’s authorized agent. The Authority Having Jurisdiction shall be permitted to require evidence to indicate such authority.
(6) Give such other data and information in accordance with the Authority Having Jurisdiction.
104.3.1 Construction Documents. Construction documents, engineering calculations, diagrams, and other data shall be submitted in two or more sets, or in a digital format where permitted by the Authority Having Jurisdiction, with each application for a permit. The construction documents, computations, and specifications shall be prepared by, and the plumbing designed by, a registered design professional. Construction documents shall be drawn to scale with clarity to identify that the intended work to be performed is in accordance with the code.
Exception: The Authority Having Jurisdiction shall be permitted to waive the submission of construction documents, calculations, or other data where the Authority Having Jurisdiction finds that the nature of the work applied for is such that reviewing of construction documents is not necessary to obtain compliance with the code.
104.3.2 Plan Review Fees. Where a plan or other data is required to be submitted in accordance with Section 104.3.1, a plan review fee shall be paid at the time of submitting construction documents for review.
The plan review fees for plumbing work shall be determined and adopted by this jurisdiction.
The plan review fees specified in this subsection are separate fees from the permit fees specified in Section 104.5.
Where plans are incomplete or changed so as to require additional review, a fee shall be charged at the rate shown in Table 104.5.
104.3.3 Time Limitation of Application. Applications for which no permit is issued within 180 days following the date of application shall expire by limitation, plans and other data submitted for review thereafter, shall be returned to the applicant or destroyed by the Authority Having Jurisdiction. The Authority Having Jurisdiction shall be permitted to exceed the time for action by the applicant for a period not to exceed 180 days upon request by the applicant showing that circumstances beyond the control of the applicant have prevented the action from being taken. No application shall be extended more than once. In order to renew action on an application after expiration, the applicant shall resubmit plans and pay a new plan review fee. 104.4 Permit Issuance. The application, construction documents, and other data filed by an applicant for a permit shall be reviewed by the Authority Having Jurisdiction. Such plans shall be permitted to be reviewed by other departments of this jurisdiction to verify compliance with applicable laws under their jurisdiction. Where the Authority Having Jurisdiction finds that the work described in an application for permit and the plans, specifications, and other data filed therewith are in
CMC § 105.6.1 High relevance — show source text
[A] 105.6.1 Refusal to issue a permit. Where the application or construction documents do not conform to the requirements of pertinent laws, the code official shall reject such application in writing, stating the reasons therefor.
[A] 105.7 Validity of permit. The issuance or granting of a permit or approval of plans, specifications and computations shall not be construed to be a permit for, or an approval of, any violation of any of the provisions of this code or of any other ordinance of the jurisdiction. Permits presuming to give authority to violate or conceal the provisions of this code or other ordinances of the jurisdiction shall not be valid.
[A] 105.8 Expiration. On or after January 1, 2019, every permit issued shall become invalid unless the work on the site authorized by such permit is commenced within 12 months after its issuance or if the work authorized on the site by such permit is suspended or aban- doned for a period of 12 months after the time the work is commenced. The building official is authorized to grant, in writing, one or more extensions of time for periods not more than 180 days each. The extension shall be requested in writing and justifiable cause demon- strated. (See Health and Safety Code Section 18938.5 and 18938.6.)
[A] 105.9 Retention of permits. Permits shall at all times be kept on the premises designated therein and shall at all times be subject to inspection by the code official or other authorized representative.
[A] 105.10 Revocation of permits. Permits issued under this code can be suspended or revoked where it is determined by the code official that:
- It is used by a person other than the person to whom the permit was issued.
- It is used for a location other than that for which the permit was issued.
- Any of the conditions or limitations set forth in the permit have been violated.
- The permittee fails, refuses or neglects to comply with any order or notice duly served on him or her under the provisions of this code within the time provided therein.
- There has been any false statement or misrepresentation as to material fact in the application or plans on which the permit or application was made.
- The permit is issued in error or in violation of any other ordinance, regulations or provisions of this code.
The code official is allowed to, in writing, suspend or revoke a permit issued under the provisions of this code whenever the permit is issued in error or on the basis of incorrect information supplied, or in violation of any ordinance or regulation or any of the provisions of this code.
SECTION 106—CONSTRUCTION DOCUMENTS
[A] 106.1 General. Plans, engineering calculations, diagrams and other data shall be submitted in not fewer than two sets, or in a digital format where allowed by the code official, with each application for a permit. The construction documents shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed. Where special conditions exist, the code official is authorized to require additional documents to be prepared by a registered design professional.
Exception: Submission of plans, calculations, construction inspection requirements and other data, if it is found that the nature of the work applied for is such that reviewing of plans is not necessary to obtain compliance with this code.
CMC § 150.2 High relevance — show source text
Air seal all accessible areas of the ceiling plane between the attic and the conditioned space in accordance with the requirements in Title 24, Part 6 Section 150.2(b)1Jii.
Exception 1 to Section A4.204.1.1: Where the capacity of the existing main electrical service panel is insufficient to supply the electrical capacity of a heat pump and where the existing main electrical service panel is sufficient to supply a new or replacement air conditioner, as calculated according to the requirements of California Electrical Code Article 220.83 or 220.87. Documentation of electrical load calculations in accordance with Article 220 must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.
Exception 2 to Section A4.204.1.1: Where the required capacity of a heat pump to meet the system selection requirements of Section 150.0(h)5 is greater than or equal to 12,000 Btu/h more than the required capacity of an air conditioner to meet the design cooling load. Documentation of heating and cooling load calculations in accordance with 150.0(h) must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.
A4.204.1.2 Altered pool and/or spa heating for existing multifamily buildings. Alteration of an existing multifamily pool and/or spa heating system shall meet the following:
Heating source sizing. Heating systems or equipment for pools or spas shall meet one of the sizing requirements of Items 1 through 5 below:
- A solar pool heating system with a solar collector surface area that is equivalent to 65 percent or greater of the surface areas of the pool or spa or a combination of both respectively; or
- A heat pump pool heater as the primary heating system that meets the sizing requirements of Reference Joint Appendix JA16.3. The control for the heat pump pool heater shall meet the requirements specified in Title 24, Part 6, Section 110.4(d). The supplementary heater can be of any energy source; or
- A heating system that derives at least 60 percent of the annual heating energy from on-site renewable energy or on-site recovered energy; or
- A combination of a solar pool heating system and heat pump pool heater without any additional supplementary heater; or
- A pool heating system determined by the Energy Commission Executive Director to use no more energy than the systems specified in Item 1, 2, 3, or 4 above.
Exception 1 to A4.204.1.2: Portable electric spas compliant with 20 CCR, Section 1605.3(g)(7) of the Appliance Efficiency Regulations.
Exception 2 to A4.204.1.2: A pool or spa that is heated solely by a solar pool heating system without any supplementary heater.
Exception 3 to A4.204.1.2: An existing building with inadequate Solar Access Roof Area (SARA) as specified in Title 24, Part 6, Section 170.2(f) for a solar pool heating system to be installed.
Exception 4 to A4.204.1.2: Heating systems which are used exclusively for permanent spa applications in existing buildings with gas availability.
Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25402, 25402.1, 25402.4 and 25402.8, Public Resources Code.
CMC § 106.3 High relevance — show source text
[A] 106.3 Site plan. In addition to the requirements for plans in the California Building Code, site plans shall include topography, width and percent of grade of access roads, landscape and vegetation details, locations of structures or building envelopes, existing or proposed overhead utilities, occupancy classification of buildings, types of ignition-resistant construction of buildings, structures and their appendages, roof classification of buildings and site water supply systems. The code official is authorized to waive or modify the requirement for a site plan where the application for permit is for alteration or repair or where otherwise warranted.
[A] 106.4 Vegetation management compliance . Prior to the building permit final approval, the property shall be in compliance with the vegetation management requirements prescribed in Section 603, including California Public Resources Code 4291 or California Government Code Section 51182. Acceptable methods of compliance inspection and documentation shall be determined by the enforc- ing agency and shall be permitted to include any of the following: 1. Local, state or federal fire authority or designee authorized to enforce vegetation management requirements. 2. Enforcing agency.
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3. Third-party inspection and certification authorized to enforce vegetation management requirements. 4. Property owner certification authorized by the enforcing agency.
[A] 106.5 Fire protection plan. Where required by the code official pursuant to Section 602, a fire protection plan shall be prepared and shall be submitted to the code official for review and approved as a part of the plans required for a permit.
[A] 106.6 Other data and substantiation. Where required by the code official, the plans and specifications shall include classification of fuel loading, fuel model light, medium or heavy, and substantiating data to verify classification of fire-smart vegetation.
[A] 106.7 Vicinity plan. In addition to the requirements for site plans, plans shall include details regarding the vicinity within 300 feet (91 440 mm) of lot lines, including other structures, slope, vegetation, fuel breaks, water supply systems and access roads.
[A] 106.8 Retention of plans. One set of approved plans, specifications and computations shall be retained by the code official for a period of not less than 180 days from date of completion of the permitted work or as required by state or local laws; and one set of approved plans and specifications shall be returned to the applicant, and said set shall be kept on the site of the building, use or work at all times during which the work authorized thereby is in progress. Refer to Building Standards Law, Health and Safety Code Sections 19850 and 19851 for permanent retention of plans.
[A] 106.9 Examination of documents. The code official shall examine or cause to be examined the accompanying construction documents and shall ascertain by such examinations whether the construction indicated and described is in accordance with the requirements of this code and other pertinent laws or ordinances.
[A] 106.10 Amended construction documents. Work shall be installed in accordance with the approved construction documents, and changes made during construction that are not in compliance with the approved documents shall be resubmitted for approval as an amended set of construction documents.
CMC § 106.1 High relevance — show source text
- It is used by a person other than the person to whom the permit was issued.
- It is used for a location other than that for which the permit was issued.
- Any of the conditions or limitations set forth in the permit have been violated.
- The permittee fails, refuses or neglects to comply with any order or notice duly served on him or her under the provisions of this code within the time provided therein.
- There has been any false statement or misrepresentation as to material fact in the application or plans on which the permit or application was made.
- The permit is issued in error or in violation of any other ordinance, regulations or provisions of this code.
The code official is allowed to, in writing, suspend or revoke a permit issued under the provisions of this code whenever the permit is issued in error or on the basis of incorrect information supplied, or in violation of any ordinance or regulation or any of the provisions of this code.
SECTION 106—CONSTRUCTION DOCUMENTS
[A] 106.1 General. Plans, engineering calculations, diagrams and other data shall be submitted in not fewer than two sets, or in a digital format where allowed by the code official, with each application for a permit. The construction documents shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed. Where special conditions exist, the code official is authorized to require additional documents to be prepared by a registered design professional.
Exception: Submission of plans, calculations, construction inspection requirements and other data, if it is found that the nature of the work applied for is such that reviewing of plans is not necessary to obtain compliance with this code.
[A] 106.2 Information on plans and specifications. Plans and specifications shall be drawn to scale on substantial paper or cloth and shall be of sufficient clarity to indicate the location, nature and extent of the work proposed, and show in detail that it will conform to the provisions of this code and relevant laws, ordinances, rules and regulations.
[A] 106.3 Site plan. In addition to the requirements for plans in the California Building Code, site plans shall include topography, width and percent of grade of access roads, landscape and vegetation details, locations of structures or building envelopes, existing or proposed overhead utilities, occupancy classification of buildings, types of ignition-resistant construction of buildings, structures and their appendages, roof classification of buildings and site water supply systems. The code official is authorized to waive or modify the requirement for a site plan where the application for permit is for alteration or repair or where otherwise warranted.
[A] 106.4 Vegetation management compliance . Prior to the building permit final approval, the property shall be in compliance with the vegetation management requirements prescribed in Section 603, including California Public Resources Code 4291 or California Government Code Section 51182. Acceptable methods of compliance inspection and documentation shall be determined by the enforc- ing agency and shall be permitted to include any of the following: 1. Local, state or federal fire authority or designee authorized to enforce vegetation management requirements. 2. Enforcing agency.
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3. Third-party inspection and certification authorized to enforce vegetation management requirements. 4. Property owner certification authorized by the enforcing agency.
CMC § 204.1.1 High relevance — show source text
A4.204.1.1 Altered space-conditioning system serving existing single-family dwelling units – mechanical cooling. When a space-conditioning system serving an existing single-family dwelling unit is altered in Climate Zones 1 through 14 and 16 by installation or replacement of an air conditioner, the altered system shall comply with either a or b below in addition to the requirements for installation specified by Title 24, Part 6, Sections 150.2(b)1E and 150.2(b)1F: a. A heat pump shall be the primary heating source and sized according to the system selection requirements specified by Title 24, Part 6 of Section 150.0(h)5. Supplemental heating may be provided by an existing gas furnace or existing electric resistance heating; or b. An air conditioner shall meet the following requirements: i. R-8 duct insulation for ducts located in unconditioned space; and ii. The duct system measured air leakage shall be equal to or less than 5 percent of the system air handler airflow as confirmed through field verification and diagnostic testing, per the requirements in Title 24, Part 6, Reference Residential Appendix Section RA3.1.4.3.1; and iii. Demonstrate, in every control mode, airflow greater than or equal to 400 CFM per ton of nominal cooling capacity through the return grilles, and an air-handling unit fan efficacy less than or equal to 0.35 W/CFM. The airflow rate and fan efficacy requirements in this section shall be confirmed through field verification and diagnostic testing, following the procedures outlined in Title 24, Part 6, Reference Residential Appendix RA3.3; and iv. In all climate zones refrigerant charge verification requirements shall meet the requirements in Title 24, Part 6 Section 150.2(b)1Fiib; and v. Vented attics shall have insulation installed to achieve a U -factor of 0.020 or insulation installed at the ceiling level shall result in an insulated thermal resistance of R-49 or greater for the insulation alone; and vi. Air seal all accessible areas of the ceiling plane between the attic and the conditioned space in accordance with the requirements in Title 24, Part 6 Section 150.2(b)1Jii.
Exception 1 to Section A4.204.1.1: Where the capacity of the existing main electrical service panel is insufficient to supply the electrical capacity of a heat pump and where the existing main electrical service panel is sufficient to supply a new or replacement air conditioner, as calculated according to the requirements of California Electrical Code Article 220.83 or 220.87. Documentation of electrical load calculations in accordance with Article 220 must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.
Exception 2 to Section A4.204.1.1: Where the required capacity of a heat pump to meet the system selection requirements of Section 150.0(h)5 is greater than or equal to 12,000 Btu/h more than the required capacity of an air conditioner to meet the design cooling load. Documentation of heating and cooling load calculations in accordance with 150.0(h) must be submitted to the enforcement agency prior to permitting for both the heat pump and proposed air conditioner.
A4.204.1.2 Altered pool and/or spa heating for existing multifamily buildings. Alteration of an existing multifamily pool and/or spa heating system shall meet the following:
Heating source sizing. Heating systems or equipment for pools or spas shall meet one of the sizing requirements of Items 1 through 5 below: 1.
CMC § 801.0 High relevance — show source text
Part I
E 801.0 Heating, Ventilation, and Air Conditioning Systems Commissioning. E 801.1 Applicability. The provisions of this section apply to the commissioning of commercial and institutional HVAC systems.
E 802.0 Commissioning. E 802.1 Commissioning Requirements. HVAC commissioning shall be included in the design and construction processes of the project to verify that the HVAC systems and components meet the owner’s project requirements and in accordance with this appendix. Commissioning shall be performed in accordance with this appendix by personnel trained and certified in commissioning by a nationally recognized organization. Commissioning requirements shall include the following:
(1) Owner’s project requirements
(2) Basis of design
(3) Commissioning measures shown in the construction doc uments
(4) Commissioning plan
(5) Functional performance
(6) Testing
(7) Post construction documentation and training
(8) Commissioning report
2025 CALIFORNIA MECHANICAL CODE 479
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APPENDIX E
HVAC systems and components covered by this appendix as well as process equipment and controls, and renewable energy systems shall be included in the scope of the commissioning requirements. E 802.2 Owner’s Project Requirements (OPR). The performance goals and requirements of the HVAC system shall be documented before the design phase of the project begins. This documentation shall include not less than the following:
(1) Environmental and sustainability goals
(2) Energy efficiency goals
(3) Indoor environmental quality requirements
(4) Equipment and systems performance goals
(5) Building occupant and O&M personnel expectations E 802.3 Basis of Design (BOD). A written explanation of how the design of the HVAC system meets the owner’s project requirements shall be completed at the design phase of the building project, and updated as necessary during the design and construction phases. The basis of design document shall cover not less than the following systems:
(1) Heating, ventilation, air conditioning (HVAC) systems and controls
(2) Water heating systems
(3) Renewable energy systems E 802.4 Commissioning Plan. A commissioning plan shall be completed to document the approach to how the project will be commissioned, and shall be started during the design phase of the building project. The commissioning plan shall include not less than the following:
(1) General project information
(2) Commissioning goals
(3) Systems to be commissioned. Plans to test systems and components shall include not less than the following:
(a) A detailed explanation of the original design intent.
(b) Equipment and systems to be tested, including the extent of tests.
(c) Functions to be tested.
(d) Conditions under which the test shall be performed.
(e) Measurable criteria for acceptable performance.
(4) Commissioning team information.
(5) Commissioning process activities, schedules, and responsibilities. Plans for the completion of commissioning requirements listed in Section E 802.5 through Section E 802.7 shall be included.
E 802.5 Functional Performance Testing. Functional performance tests shall demonstrate the correct installation and operation of each component, system, and system-to-system interface in accordance with the approved plans and specifications. Functional performance testing reports shall contain information addressing each of the building components tested, the testing methods utilized, and readings and adjustments made.
CMC § 802.3 High relevance — show source text
(5) Building occupant and O&M personnel expectations E 802.3 Basis of Design (BOD). A written explanation of how the design of the HVAC system meets the owner’s project requirements shall be completed at the design phase of the building project, and updated as necessary during the design and construction phases. The basis of design document shall cover not less than the following systems:
(1) Heating, ventilation, air conditioning (HVAC) systems and controls
(2) Water heating systems
(3) Renewable energy systems E 802.4 Commissioning Plan. A commissioning plan shall be completed to document the approach to how the project will be commissioned, and shall be started during the design phase of the building project. The commissioning plan shall include not less than the following:
(1) General project information
(2) Commissioning goals
(3) Systems to be commissioned. Plans to test systems and components shall include not less than the following:
(a) A detailed explanation of the original design intent.
(b) Equipment and systems to be tested, including the extent of tests.
(c) Functions to be tested.
(d) Conditions under which the test shall be performed.
(e) Measurable criteria for acceptable performance.
(4) Commissioning team information.
(5) Commissioning process activities, schedules, and responsibilities. Plans for the completion of commissioning requirements listed in Section E 802.5 through Section E 802.7 shall be included.
E 802.5 Functional Performance Testing. Functional performance tests shall demonstrate the correct installation and operation of each component, system, and system-to-system interface in accordance with the approved plans and specifications. Functional performance testing reports shall contain information addressing each of the building components tested, the testing methods utilized, and readings and adjustments made.
E 802.6 Post Construction Documentation and Train- ing. A system manual and systems operations training are required.
E 802.6.1 Systems Manual. Documentation of the operational aspects of the HVAC system shall be completed within the systems manual and delivered to the building owner and facilities operator. The systems manual shall include not less than the following:
(1) Site information, including facility description, history, and current requirements.
(2) Site contact information.
(3) Basic O&M, including general site operating procedures, basic troubleshooting, recommended maintenance requirements, and site events log.
(4) Major systems.
(5) Site equipment inventory and maintenance notes.
(6) Equipment/system warranty documentation and information.
(7) “As-Built” design drawings.
(8) Other resources and documentation.
E 802.6.2 Systems Operations Training. The training of the appropriate maintenance staff for each equipment type or system shall include not less than the following:
(1) System/Equipment overview (what it is, what it does, and what other systems or equipment it interfaces with).
(2) Review of the information in the systems manual.
(3) Review of the record drawings on the system/equip ment.
E 802.7 Commissioning Report. A complete report of commissioning process activities undertaken through the design, construction, and post-construction phases of the building project shall be completed and provided to the
owner.
Part II
E 803.0 Commissioning Acceptance.
E 803.1 General. Part II of this appendix provides a means of verifying the commissioning requirements of Section E 802.1. The activities specified in Part II of this appendix includes three aspects, as described as follows:
CMC § 2207.3 High relevance — show source text
2207.3 Calculations. The steel joist and joist girder manufacturer shall design the steel joists and steel joist girders in accordance with SJI 100 or SJI 200 to support the load requirements of Section 2207.2. The registered design professional shall be permitted to require submission of the steel joist and joist girder calculations as prepared by a registered design professional responsible for the product design. Where requested by the registered design professional, the steel joist manufacturer shall submit design calculations with a cover letter bearing the seal and signature of the joist manufacturer’s registered design professional. In addition to the design calculations submitted under seal and signature, the following shall be included:
- Bridging design that differs from SJI 100 or SJI 200, such as cantilevered conditions and net uplift.
- Connection design for: 2.1. Connections that differ from SJI 100 or SJI 200, such as flush-framed or framed connections.
2.2. Field splices.
2.3. Joist headers.
2207.4 Steel joist drawings. Steel joist placement plans shall be provided to show the steel joist products as specified on the approved construction documents and are to be utilized for field installation in accordance with specific project requirements as stated in Section 2207.2. Steel joist placement plans shall include, at a minimum, the following:
- Listing of applicable loads as stated in Section 2207.2 and used in the design of the steel joists and joist girders as specified in the approved construction documents.
- Profiles for joist and joist girder configurations that differ from those defined by SJI 100 or SJI 200.
- Connection requirements for:
3.1. Joist supports. 3.2. Joist girder supports. 3.3. Field splices. 3.4. Bridging attachments. 4. Deflection criteria for joists and joist girder configurations that differ from those defined by SJI 100 or SJI 200. 5. Size, location and connections for bridging.
- Joist headers.
Steel joist placement plans do not require the seal and signature of the joist manufacturer’s registered design professional.
[OSHPD 1R, 2 & 5] Not permitted by OSHPD.
2207.5 Certification. At completion of manufacture, the steel joist manufacturer shall submit a certificate of compliance to the owner or the owner’s authorized agent for submittal to the building official as specified in Section 1704.5 stating that work was performed in accordance with approved construction documents and with SJI 100 or SJI 200, as applicable.
2207.6 Joist chord bracing. [OSHPD 1R, 2 & 5] The chords of all joists shall be laterally supported at all points where the chords change direction.
SECTION 2208—STEEL DECK
2208.1 Steel decks. The design and construction of cold-formed steel floor and roof decks and composite slabs of concrete and steel deck shall be in accordance with SDI SD. The design of cold-formed steel diaphragms shall be in accordance with additional provisions of AISI S310, as applicable.
[OSHPD 1R, 2 & 5] The base material thickness of the steel deck shall not be less than 0.0359 inch (0.9 mm) (20 gage).
Frequently asked questions
Do I always need a registered design professional (RDP) to prepare process‑piping plans?
Not always. § 1403.1 permits the AHJ to require plans to be prepared by an RDP; whether it is required depends on the AHJ and local statutes. Check the AHJ’s submittal checklist.
How many physical sets of drawings must I submit?
Chapter 14 says one or more sets under § 1403.1, but the general rules in § 104.3.1 typically require two or more sets (or digital files). Follow the AHJ’s checklist to resolve which applies.
Will I have to pay a plan review fee?
Yes — if plans or other data are submitted for review a plan review fee is due, as referenced in § 1403.1 and detailed in § 104.3.2. The amount is set by the jurisdiction.
Can the AHJ waive plans and calculations?
Yes. The general construction‑document exception in § 104.3.1 permits the AHJ to waive submission where the nature of the work makes review unnecessary.
What if my drawings aren’t drawn to scale or clear?
The AHJ can reject incomplete or unclear documents; § 104.3.1 requires construction documents to be drawn to scale and with sufficient clarity to demonstrate code compliance.
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