CMC · California Mechanical Code
What inspections are required during and after installation?
Before you cover or backfill any process piping, notify the building department for a rough inspection; after concealment the final inspection requires a pressure test (hydraulic = 1.5× design pressure or pneumatic = 110%) held at least 30 minutes with no perceptible drop, witnessed by the AHJ.
Last reviewed: July 6, 2026
What the code requires — plain English
The California Mechanical Code requires the permit holder to notify the enforcing agency when process piping is ready for inspection and forbids concealment of installed piping before inspection. The Authority Having Jurisdiction (AHJ) must perform a rough piping inspection before piping is covered and a final piping inspection after installation—during the final inspection the piping must pass a pressure test with specified pressures and minimum hold time. See § 1405.1, § 1405.2.1, and § 1405.2.2 for these requirements.
Never cover or conceal process piping before the AHJ has had the opportunity to perform the required rough inspection; final approval requires a pressure test held to the code-specified pressure and time. § 1405.1; § 1405.2.1; § 1405.2.2.
Requirements in detail
Who is responsible
- The permit holder (or their agent) must notify the AHJ when piping is ready for inspection; the AHJ is responsible for performing the inspections. See § 1405.1.
When inspections must occur
- Before concealment: the Rough Piping Inspection must occur after piping is installed but before it is covered or concealed. See § 1405.2.1.
- After concealment/at completion: the Final Piping Inspection occurs after the piping is installed and any portions that will be concealed have been concealed; the AHJ must witness required tests during this inspection. See § 1405.2.2.
Tests and acceptance criteria (final inspection)
- Test types: hydraulic testing or pneumatic testing are specified for pressure verification. See § 1405.2.2.
- Required test pressures:
- Hydraulic test: not less than one-and-one-half times the maximum designed operating pressure. See § 1405.2.2.
- Pneumatic test: not less than 110 percent of the maximum designed operating pressure. See § 1405.2.2.
- Minimum hold time: test pressure shall be held for a period satisfactory to the AHJ, but not less than 30 minutes, with no perceptible drop in pressure. See § 1405.2.2.
- Test presence and equipment: tests must be made in the presence of the AHJ and the permit holder must furnish necessary apparatus for tests. See § 1405.2.2.
Underground piping
- Excavations needed for underground piping must remain open until the piping has been inspected and approved. If the piping is covered before approval, it must be exposed on the AHJ’s direction. See § 1405.1.
Decision table — what to expect and when
| Inspection Type | When performed | Key decision-relevant value(s) | Code Reference |
|---|---|---|---|
| Rough Piping Inspection | After installation and before piping is covered/concealed | Verify piping size, material, installation per code | § 1405.2.1 |
| Final Piping Inspection | After installation and after concealed portions are concealed | Must pass pressure test: hydraulic = 1.5× design pressure OR pneumatic = 110%, hold ≥ 30 minutes with no perceptible drop; AHJ must witness test; permit holder provides apparatus | § 1405.2.2 |
| Underground Excavation | Before backfill | Excavation kept open until inspected & approved; if covered before approval, AHJ may require exposure | § 1405.1 |
Exceptions & special cases
- The code allows the AHJ to direct that covered underground piping be exposed for inspection if it was concealed before approval — the permit holder must comply. See § 1405.1.
- The AHJ may accept an alternate schedule or additional tests where satisfactory (the code gives the AHJ discretion about acceptable hold times and presence for tests), but the minimums in § 1405.2.2 are mandatory.
- (Related authority) The AHJ may require additional or special inspections in other parts of the code (see related provisions below) — always check local AHJ rules for any jurisdictional enhancements.
Common mistakes
- Covering piping before the rough inspection is performed. The code explicitly prohibits concealment prior to inspection. See § 1405.2.1 and § 1405.1.
- Using the wrong test pressure: applying only 100% of design pressure (insufficient) or miscalculating the multiplier (%). Remember hydraulic = 1.5×; pneumatic = 110%. See § 1405.2.2.
- Holding the test for less than 30 minutes (or not meeting the AHJ’s required duration). The code requires no less than 30 minutes and no perceptible pressure drop. See § 1405.2.2.
- Not having necessary testing apparatus available or attempting to run the test without the AHJ present—tests must be made in the presence of the AHJ, and equipment supplied by the permit holder. See § 1405.2.2.
Worked example — concrete scenario
Scenario: A process piping system is installed with a maximum designed operating pressure of 100 psi. The contractor must schedule both rough and final inspections.
Steps and numbers:
- After installing piping and before covering, the contractor notifies the AHJ for the Rough Piping Inspection to verify size, material and installation. Reference: § 1405.2.1.
- After concealment is completed and the system is ready for use, the contractor schedules the Final Piping Inspection. Reference: § 1405.2.2.
- Testing options and required pressures:
- If doing a hydraulic test, apply at least 1.5 × 100 psi = 150 psi. Hold for a time satisfactory to the AHJ but no less than 30 minutes, with no perceptible drop. AHJ must be present. § 1405.2.2.
- If doing a pneumatic test, apply at least 110% × 100 psi = 110 psi, with the same hold-time and observation requirements. § 1405.2.2.
- The permit holder brings the pressure gauges and pumping apparatus; the AHJ observes and either approves the piping or issues corrections. § 1405.2.2; § 1405.1.
Related provisions
- § 1405.1 — Notification, keeping excavations open, exposure on AHJ direction.
- § 1405.2.1 — Rough Piping Inspection timing and scope (size, material, installation).
- § 1405.2.2 — Final Piping Inspection: pressure-test requirements, hold time, AHJ presence, apparatus provided by permit holder.
- § 1405.2 — Overview that AHJ shall make the listed inspections and either approve or notify of noncompliance.
- (Related administrative inspection rules) § 105.1 / § 105.2 — General inspection requirements and scheduling for mechanical systems (see CMC Division II: inspections and testing).
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 1405.2 High relevance — show source text
Excavations required for the installation of underground piping shall be kept open until such time as the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.
1405.2 Required Inspections. The Authority Having Jurisdiction shall make the following inspections and shall either approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.
1405.2.1 Rough Piping Inspection. This inspection shall be made after process piping authorized by the permit has been installed and before piping has been cov
ered or concealed. This inspection shall include a determination that the piping size, material, and installation are in accordance with the requirements of this code.
1405.2.2 Final Piping Inspection. This inspection shall be made after piping authorized by the permit has been installed and after portions thereof that are to be covered or concealed are so concealed. This inspection shall include a pressure test, at which time the piping shall stand a pressure of not less than one-and-one-half times the maximum designed operating pressure where hydraulic testing is conducted or 110 percent where testing is conducted pneumatically. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes with no perceptible drop in pressure. HPM drain, waste, and vent piping shall be tested in accordance with the plumbing code. Tests shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder.
1405.3 Other Inspections. In addition to the inspections required by this section, the Authority Having Jurisdiction shall be permitted to require a special inspector, as specified in the building code, during installation of piping systems. In cases where the work authorized was installed in accordance with plans and specifications prepared by a registered design professional, the Authority Having Jurisdiction shall be permitted to require a final signed report stating that the work was installed in accordance with approved plans and specifications and the applicable provisions of this chapter.
1406.0 Pipe, Tubing, and Fittings.
1406.1 General. Process pipe, tubing, and fittings shall comply with ASME B31.3 and shall be installed in accordance with the manufacturer’s installation instructions. Materials shall be rated for the operating temperatures and pressures of the system, and shall be compatible with the type of liquid.
1406.2 Hazardous Process Piping (HPP). HPP supply piping or tubing in service corridors shall be exposed to view. HPP piping shall be identified in accordance with nationally recognized standards to indicate the material being transported. Liquid HPP piping shall have an approved means for directing spilled materials to an approved containment or drainage system.
Liquid HPP waste or drainage systems shall be installed in accordance with the plumbing code.
1406.2.1 Installation in Exit Corridors and Above Other Occupancies. Hazardous process supply pipe shall not be located within exit corridors, within a portion of a means of egress required to be enclosed in fire-resistive construction, or in concealed spaces in or above
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PROCESS PIPING
areas not classified as Group H Occupancies, except as permitted by this subsection.
CMC § 1401.0 High relevance — show source text
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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.
1405.0 Inspections.
1405.1 General. Upon completion of the installation, alteration, or repair of process piping, and prior to the use thereof, the Authority Having Jurisdiction shall be notified that such piping is ready for inspection.
Excavations required for the installation of underground piping shall be kept open until such time as the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.
1405.2 Required Inspections. The Authority Having Jurisdiction shall make the following inspections and shall either approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.
1405.2.1 Rough Piping Inspection. This inspection shall be made after process piping authorized by the permit has been installed and before piping has been cov
ered or concealed. This inspection shall include a determination that the piping size, material, and installation are in accordance with the requirements of this code.
1405.2.2 Final Piping Inspection. This inspection shall be made after piping authorized by the permit has been installed and after portions thereof that are to be covered or concealed are so concealed. This inspection shall include a pressure test, at which time the piping shall stand a pressure of not less than one-and-one-half times the maximum designed operating pressure where hydraulic testing is conducted or 110 percent where testing is conducted pneumatically. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes with no perceptible drop in pressure. HPM drain, waste, and vent piping shall be tested in accordance with the plumbing code. Tests shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder.
CMC § 105.0 High relevance — show source text
(2) Refunding of not more than a percentage, as determined by this jurisdiction where no work has been done under a permit issued in accordance with this code.
The Authority Having Jurisdiction shall not authorize refunding of a fee paid except upon written application filed by the original permittee not to exceed 180 days after the date of fee payment.
105.0 Inspections and Testing. 105.1 General. Mechanical systems for which a permit is required by this code shall be inspected by the Authority Having Jurisdiction.
No mechanical system or portion thereof shall be covered, concealed, or put into use until inspected and approved as prescribed in this code. Neither the Authority Having Jurisdiction nor the jurisdiction shall be liable for expense entailed in the removal or replacement of material required to permit inspection. Mechanical systems regulated by this code shall not be connected to the energy fuel supply lines until authorized by the Authority Having Jurisdiction.
105.2 Required Inspections. New mechanical system work and such portions of existing systems as affected by new work, or changes, shall be inspected by the Authority Having Jurisdiction to ensure compliance with the requirements of this code and to ensure that the installation and construction of the mechanical system are in accordance with approved plans. The Authority Having Jurisdiction shall make the following inspections and other such inspections as necessary. The permittee or the permittee’s authorized agent shall be responsible for the scheduling of such inspections as follows:
(1) Underground inspection shall be made after trenches or ditches are excavated and bedded, piping installed, and before backfill is put in place.
(2) Rough-in inspection shall be made prior to the installation of wall or ceiling membranes.
(3) Final inspection shall be made upon completion of the installation.
105.2.1 Uncovering. Where a mechanical system, or part thereof, which is installed, altered, or repaired, is covered or concealed before being inspected, tested, and approved as prescribed in this code, it shall be uncovered for inspection after notice to uncover the work has been issued to the responsible person by the Authority Having Jurisdiction. The requirements of this section shall not be considered to prohibit the operation of mechanical systems installed to replace existing equipment serving
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DIVISION II SCOPE AND ADMINISTRATION
an occupied portion of the building in the event a request for inspection of such equipment has been filed with the Authority Having Jurisdiction not more than 72 hours after such replacement work is completed, and before a portion of such mechanical system is concealed by a permanent portion of the building. 105.2.2 Other Inspections. In addition to the inspections required by this code, the Authority Having Jurisdiction shall be permitted to require other inspections to ascertain compliance with the provisions of this code and other laws that are enforced by the Authority Having Jurisdiction.
105.2.3 Inspection Requests. It shall be the duty of the person doing the work authorized by a permit to notify the Authority Having Jurisdiction that such work is ready for inspection. The Authority Having Jurisdiction shall be permitted to require that a request for inspection be filed not less than 1 working day before such inspection is desired. Such request shall be permitted to be made in writing or by telephone, at the option of the Authority Having Jurisdiction.
It shall be the duty of the person requesting inspections in accordance with this code to provide access to and means for inspection of such work.
CMC § 1.1.1 High relevance — show source text
R109.1.1.1 Concrete slab and under-floor inspection. Concrete slab and under-floor inspections shall be made after in-slab or under-floor reinforcing steel and building service equipment, conduits, piping or other ancillary building trade products or equip- ment are installed, but before any concrete is placed or floor sheathing is installed, including the subfloor.
R109.1.2 Plumbing, mechanical, gas and electrical systems inspection. Rough inspection of plumbing, mechanical, gas and electrical systems shall be made prior to covering or concealment, before fixtures or appliances are set or installed, and prior to framing inspection.
Exception: Backfilling of ground-source heat pump loop systems tested in accordance with the California Mechanical Code prior to inspection shall be permitted.
R109.1.3 Floodplain inspections. For construction in flood hazard areas as established by Table R301.2, upon placement of the lowest floor, including basement, and prior to further vertical construction, the building official shall require submission of documentation, prepared and sealed by a registered design professional, of the elevation of the lowest floor, including basement, required in Section R306.
R109.1.4 Frame and masonry inspection. Inspection of framing and masonry construction shall be made after the roof, masonry, framing, firestopping, draftstopping and bracing are in place and after chimneys and vents to be concealed are completed and the rough electrical, plumbing, heating, wires, pipes and ducts are approved.
R109.1.4.1 Moisture content verification. Moisture content of framing members shall be verified in accordance with the Califor- nia Green Building Standards Code, Chapter 4, Division 4.5.
R109.1.4.2 Lath and gypsum board inspection. Lath and gypsum board inspections shall be made after lathing and gypsum board, interior and exterior, is in place, but before any plastering is applied or gypsum board joints and fasteners are taped and finished.
R109.1.5 Other inspections. In addition to inspections in Sections R109.1.1 through R109.1.4.2, the building official shall have the authority to make or require any other inspections to ascertain compliance with this code and other laws enforced by the building official.
R109.1.5.1 Fire-resistance-rated construction inspection. Where fire-resistance-rated construction is required between dwelling units or due to location on property, the building official shall require an inspection of such construction after lathing or gypsum panel products are in place, but before any plaster is applied, or before panel joints and fasteners are taped and finished. Protection of joints and penetrations in fire-resistance-rated assemblies shall not be concealed from view until inspected and approved.
R109.1.5.2 Special inspections. For special inspections, see California Building Code, Chapter 17.
R109.1.5.3 Weather-exposed balcony and walking surface waterproofing. Where balconies or other elevated walking surfaces are exposed to water from direct or blowing rain, snow or irrigation, and the structural framing is protected by an impervious moisture barrier, all elements of the impervious moisture barrier system shall not be concealed until inspected and approved.
Exception: Where special inspections are provided in accordance with California Building Code Section 1705.1.1, Item 3.
R109.1.6 Final inspection. Final inspection shall be made after the permitted work is complete and prior to occupancy.
CMC § 104.4.6 High relevance — show source text
104.4.6 Retention of Plans. One set of approved construction documents and computations shall be retained by the Authority Having Jurisdiction until final approval of the work is covered therein.
One set of approved construction documents, computations, and manufacturer’s installation instructions shall be returned to the applicant, and said set shall be kept on the site of the building or work at times during which the work authorized thereby is in progress.
104.5 Fees. Fees shall be assessed in accordance with the provisions of this section and as set forth in the fee schedule, Table 104.5. The fees are to be determined and adopted by this jurisdiction. 104.5.1 Work Commencing Before Permit Issuance. Where work for which a permit is required by this code has been commenced without first obtaining said permit, a special investigation shall be made before a permit is issued for such work. 104.5.2 Investigation Fees. An investigation fee, in addition to the permit fee, shall be collected whether or not a permit is then or subsequently issued. The investigation fee shall be equal to the amount of the permit fee
that is required by this code if a permit were to be issued. The payment of such investigation fee shall not exempt a person from compliance with other provisions of this code, nor from a penalty prescribed by law. 104.5.3 Fee Refunds. The Authority Having Jurisdiction shall be permitted to authorize the refunding of a fee as follows:
(1) The amount paid hereunder that was erroneously paid or collected.
(2) Refunding of not more than a percentage, as determined by this jurisdiction where no work has been done under a permit issued in accordance with this code.
The Authority Having Jurisdiction shall not authorize refunding of a fee paid except upon written application filed by the original permittee not to exceed 180 days after the date of fee payment.
105.0 Inspections and Testing. 105.1 General. Mechanical systems for which a permit is required by this code shall be inspected by the Authority Having Jurisdiction.
No mechanical system or portion thereof shall be covered, concealed, or put into use until inspected and approved as prescribed in this code. Neither the Authority Having Jurisdiction nor the jurisdiction shall be liable for expense entailed in the removal or replacement of material required to permit inspection. Mechanical systems regulated by this code shall not be connected to the energy fuel supply lines until authorized by the Authority Having Jurisdiction.
105.2 Required Inspections. New mechanical system work and such portions of existing systems as affected by new work, or changes, shall be inspected by the Authority Having Jurisdiction to ensure compliance with the requirements of this code and to ensure that the installation and construction of the mechanical system are in accordance with approved plans. The Authority Having Jurisdiction shall make the following inspections and other such inspections as necessary. The permittee or the permittee’s authorized agent shall be responsible for the scheduling of such inspections as follows:
(1) Underground inspection shall be made after trenches or ditches are excavated and bedded, piping installed, and before backfill is put in place.
(2) Rough-in inspection shall be made prior to the installation of wall or ceiling membranes.
(3) Final inspection shall be made upon completion of the installation.
CMC § 1705.7 High relevance — show source text
The duties of the geotechnical engineer or his or her qualified representative shall include, but need not be limited to, the inspec- tion of cleared areas and benches prepared to receive fill; inspection of the removal of all unsuitable soils and other materials; the approval of soils to be used as fill material; the inspection of placement and compaction of fill materials; the testing of the completed fills; and the inspection or review of geotechnical drainage devices, buttress fills or other similar protective measures in accordance with the approved construction documents.
A verified report shall be submitted by the geotechnical engineer as required by the California Administrative Code. The report shall indicate that all tests and inspections required by the approved construction documents were completed and whether the tested materials and/or inspected work meet the requirements of the approved construction documents.
1705.7 Driven deep foundations. Special inspections and tests shall be performed during installation of driven deep foundation elements as specified in Table 1705.7. The approved geotechnical report and the construction documents prepared by the registered design professionals shall be used to determine compliance.
TABLE 1705.7—REQUIRED SPECIAL INSPECTIONS AND TESTS OF DRIVEN DEEP FOUNDATION ELEMENTS Col2 Col3 TYPE CONTINUOUS
SPECIAL INSPECTIONPERIODIC
SPECIAL
INSPECTION1. Verify element materials, sizes and lengths comply with the requirements. X — 2. Determine capacities of test elements and conduct additional load tests, as required. X — 3. Inspect driving operations and maintain complete and accurate records for each element. X — 4. Verify placement locations and plumbness, confirm type and size of hammer, record number
of blows per foot of penetration, determine required penetrations to achieve design capacity,
record tip and butt elevations and document any damage to foundation element.X — 5. For steel elements, perform additional special inspections in accordance with Section 1705.2. In accordance with Section 1705.2 In accordance with Section 1705.2 6. For concrete elements and concrete-filled elements, perform tests and additional special
inspections in accordance with Section 1705.3.In accordance with Section 1705.3 In accordance with Section 1705.3 7.For specialty elements, perform additional inspections as determined by the registered design
professional in responsible charge.In accordance with Statement of Special
InspectionsIn accordance with Statement of Special
Inspections1705.7.1 Driven deep foundations observation. [OSHPD 1R, 2 & 5] The installation of driven deep foundations shall be continu- ously observed by a qualified representative of the geotechnical engineer responsible for that portion of the project.
The representative of the geotechnical engineer shall make a report of the deep foundation pile-driving operation giving such pertinent data as the physical characteristics of the deep foundation pile-driving equipment, identifying marks for each deep founda- tion pile, total depth of embedment for each deep foundation; and when the allowable deep foundation pile loads are determined by a dynamic load formula, the design formula used, and the permanent penetration under the last 10 blows. One copy of the report shall be sent to the enforcement agency.
CMC § 6.4 High relevance — show source text
- Installation and anchorage of ductwork designed to carry hazardous materials in structures assigned to Seismic Design Category C, D, E or F.
- Installation and anchorage of vibration isolation systems in structures assigned to Seismic Design Category C, D, E or F where the approved construction documents require a nominal clearance of [1] / 4 inch (6.4 mm) or less between the equipment support frame and restraint.
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- Installation of mechanical and electrical equipment, including duct work, piping systems and their structural supports, where automatic sprinkler systems are installed in structures assigned to Seismic Design Category C, D, E or F to verify one of the following: 6.1. Minimum clearances have been provided as required by Section 13.2.4 ASCE/SEI 7. 6.2. A nominal clearance of not less than 3 inches (76 mm) has been be provided between automatic sprinkler system drops and sprigs and: structural members not used collectively or independently to support the sprinklers; equipment attached to the building structure; and other systems’ piping.
Where flexible sprinkler hose fittings are used, special inspection of minimum clearances is not required.
1705.13.7 Storage racks. Steel storage racks and steel cantilevered storage racks that are 8 feet (2438 mm) in height or greater and assigned to Seismic Design Category D, E or F shall be provided with periodic special inspection as required by Table 1705.13.7.
TABLE 1705.13.7—REQUIRED INSPECTIONS OF STORAGE RACK SYSTEMS Col2 Col3 Col4 Col5 TYPE CONTINUOUS
INSPECTIONPERIODIC
INSPECTIONREFERENCED
STANDARDIBC REFERENCE 1. Materials used, to verify compliance with one or more of the
material test reports in accordance with the approved
construction documents.— X — — 2. Fabricated storage rack elements. — X — Section 1704.2.5 3. Storage rack anchorage installation. — X ANSI/MH16.1
Section 7.3.2— 4. Completed storage rack system, to indicate compliance with
the approved construction documents.— X — — 1705.13.8 Seismic isolation systems. Periodic special inspection shall be provided for seismic isolation systems in seismically isolated structures assigned to Seismic Design Category B, C, D, E or F during the fabrication and installation of isolator units and energy dissipation devices.
1705.13.9 Cold-formed steel special bolted moment frames. Periodic special inspection shall be provided for the installation of cold-formed steel special bolted moment frames in the seismic force-resisting systems of structures assigned to Seismic Design Category D, E or F.
1705.14 Testing for seismic resistance. Testing for seismic resistance shall be required as specified in Sections 1705.14.1 through 1705.14.4, unless exempted from special inspections by the exceptions of Section 1704.2.
CMC § 1705.16 High relevance — show source text
[BF] 1705.16 Intumescent fire-resistive materials. Special inspections and tests for intumescent fire-resistive materials applied to structural elements and decks shall be performed in accordance with AWCI 12-B. Special inspections and tests shall be based on the fire-resistance design as designated in the approved construction documents. Special inspections and tests shall be performed during construction. Additional visual inspection shall be performed after the rough installation and, where applicable, prior to the concealment of electrical, automatic sprinkler, mechanical and plumbing systems.
[BF] 1705.17 Exterior insulation and finish systems (EIFS). Special inspections shall be required for all EIFS applications.
Exceptions:
- Special inspections shall not be required for EIFS applications installed over a water-resistive barrier with a means of draining moisture to the exterior.
- Special inspections shall not be required for EIFS applications installed over masonry or concrete walls.
[BF] 1705.17.1 Water-resistive barrier coating. A water-resistive barrier coating complying with ASTM E2570 requires special inspection of the water-resistive barrier coating where installed over a sheathing substrate.
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[BF] 1705.18 Fire-resistant penetrations and joints. In high-rise buildings, in buildings assigned to Risk Category III or IV, or in fire areas containing Group R occupancies with an occupant load greater than 250, special inspections for through-penetrations, membrane penetration firestops, fire-resistant joint systems and perimeter fire containment systems that are tested and listed in accordance with Sections 714.4.1.2, 714.5.1.2, 715.3.1 and 715.4 shall be in accordance with Section 1705.18.1 or 1705.18.2.
[OSHPD 1R, 2 & 5] Buildings assigned to all Risk Categories shall be subject to special inspections for fire-resistant penetrations and joints.
[BF] 1705.18.1 Penetration firestops. Inspections of penetration firestop systems that are tested and listed in accordance with Sections 714.4.1.2 and 714.5.1.2 shall be conducted by an approved agency in accordance with ASTM E2174.
[BF] 1705.18.2 Fire-resistant joint systems. Inspection of fire-resistant joint systems that are tested and listed in accordance with Sections 715.3.1 and 715.4 shall be conducted by an approved agency in accordance with ASTM E2393.
[F] 1705.19 Testing for smoke control. Smoke control systems shall be tested by a special inspector.
[F] 1705.19.1 Testing scope. The test scope shall be as follows:
During erection of ductwork and prior to concealment for the purposes of leakage testing and recording of device location.
Prior to occupancy and after sufficient completion for the purposes of pressure difference testing, flow measurements and detection and control verification.
[F] 1705.19.2 Qualifications. Approved agencies for smoke control testing shall have expertise in fire protection engineering, mechanical engineering and certification as air balancers.
CMC § 7-115 High relevance — show source text
1704 A .1 General. Special inspections and tests, statements of special inspections, responsibilities of contractors, submittals to the building official and structural observations shall meet the applicable requirements of this section.
1704 A .2 Special inspections and tests. Where application is made to the building official for construction as specified in Section 105 the owner shall employ one or more approved agencies to provide special inspections and tests during construction on the types of work specified in Section 1705 A and identify the approved agencies to the building official. These special inspections and tests are in addition to the inspections by the building official that are identified in Section 110.
[OSHPD 1 & 4] The inspectors shall act under the direction of the architect or structural engineer or both, and be responsible to the Owner. Where the California Administrative Code (CAC) Section 7-115 (a) 2 permits construction documents to be prepared under the
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SPECIAL INSPECTIONS AND TESTS
responsible charge of a mechanical, electrical or civil engineer, inspectors shall be permitted to work under the direction of engineer in appropriate branch as permitted therein.
Exceptions:
- Special inspections and tests are not required for construction of a minor nature or as warranted by conditions in the jurisdiction as approved by the building official.
- [DSA-SS, DSA-SS/CC] Reference to Section 105 and Section 110 shall be to the California Administrative Code instead.
1704 A .2.1 Special inspector qualifications. Prior to the start of the construction, the approved agencies shall provide written documentation to the building official demonstrating the competence and relevant experience or training of the special inspectors who will perform the special inspections and tests during construction. Experience or training shall be considered to be relevant where the documented experience or training is related in complexity to the same type of special inspection or testing activities for projects of similar complexity and material qualities. These qualifications are in addition to qualifications specified in other sections of this code.
The registered design professional in responsible charge and engineers of record involved in the design of the project are permitted to act as an approved agency and their personnel are permitted to act as special inspectors for the work designed by them, provided they qualify as special inspectors.
1704 A .2.2 Access for special inspection. The construction or work for which special inspection or testing is required shall remain accessible and exposed for special inspection or testing purposes until completion of the required special inspections or tests.
1704 A .2.3 Statement of special inspections. The applicant shall submit a statement of special inspections prepared by the regis- tered design professional in general responsible charge in accordance with Section 107.1 as a condition for construction documents review . This statement shall be in accordance with Section 1704 A .3.
[DSA-SS, DSA-SS/CC] Reference to Section 107.1 shall be to the California Administrative Code instead.
1704 A .2.4 Report requirement. The inspector(s) of record and approved agencies shall keep records of special inspections and tests.
CMC § 6.4 High relevance — show source text
Anchorage of electrical equipment for emergency and standby power systems in structures assigned to Seismic Design Category D, E or F. 2. Anchorage of other electrical equipment in structures assigned to Seismic Design Category D, E or F. 3. Installation and anchorage of piping systems designed to carry hazardous materials and their associated mechanical units in structures assigned to Seismic Design Category D, E or F. 4. Installation and anchorage of ductwork designed to carry hazardous materials in structures assigned to Seismic Design Category D, E or F. 5. Installation and anchorage of vibration isolation systems in structures assigned to Seismic Design Category D, E or F where the approved construction documents require a nominal clearance of [1] / 4 inch (6.4 mm) or less between the equipment support frame and restraint. 6. Installation of mechanical and electrical equipment, including duct work, piping systems and their structural supports, where automatic sprinkler systems are installed in structures assigned to Seismic Design Category D, E or F to verify one of the following: 6.1. Minimum clearances have been provided as required by Section 13.2.4 ASCE/SEI 7. 6.2. A nominal clearance of not less than 3 inches (76 mm) has been be provided between automatic sprinkler system drops and sprigs and: structural members not used collectively or independently to support the sprinklers; equipment attached to the building structure; and other systems’ piping.
Where flexible sprinkler hose fittings are used, special inspection of minimum clearances is not required.
2025 CALIFORNIA BUILDING CODE 17A-17
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
SPECIAL INSPECTIONS AND TESTS
1705 A .13.7 Storage racks. Steel storage racks and steel cantilevered storage racks that are 8 feet (2438 mm) in height or greater and assigned to Seismic Design Category D, E or F shall be provided with periodic special inspection as required by Table 1705 A .13.7.
TABLE 1705A.13.7—REQUIRED INSPECTIONS OF STORAGE RACK SYSTEMS Col2 Col3 Col4 Col5 TYPE CONTINUOUS
INSPECTIONPERIODIC
INSPECTIONREFERENCED
STANDARDIBC REFERENCE 1. Materials used, to verify compliance with one or more of the
material test reports in accordance with the approved
construction documents.— X — — 2. Fabricated storage rack elements. — X — Section 1704_A_.2.5 3. Storage rack anchorage installation. — X ANSI/MH16.1
Section 7.3.2— 4. Completed storage rack system, to indicate compliance with
the approved construction documents.— X — — �
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1705 A .13.8 Seismic isolation and damping systems. Periodic special inspection shall be provided for seismic isolation and damping systems in structures assigned to Seismic Design Category D, E or F during the fabrication and installation of isolator units and energy dissipation devices. Continuous special inspection is required for prototype and production testing of isolator units and damping devices.
CMC § 26.6.4 High relevance — show source text
- Reports of material properties verifying compliance with the requirements of AWS D1.4 for weldability as specified in Section 26.6.4 of ACI 318 for reinforcing bars in concrete complying with a standard other than ASTM A706 that are to be welded.
- Reports of mill tests in accordance with Section 20.2.2.5 of ACI 318 for reinforcing bars complying with ASTM A615 and used to resist earthquake-induced flexural or axial forces in the special moment frames, special structural walls or coupling beams connecting special structural walls of seismic force-resisting systems in structures assigned to Seismic Design Category D, E or F.
1704 A .6 Structural observations. The owner shall employ a registered design professional to perform structural observations. The structural observer shall visually observe representative locations of structural systems, details and load paths for general conformance to the approved construction documents. Structural observation does not include or waive the responsibility for the inspections in Section 110 or the special inspections in Section 1705 A or other sections of this code. Prior to the commencement of observations, the structural observer shall submit to the building official a written statement identifying the frequency and extent of structural observations. At the conclusion of the work included in the permit, the structural observer shall submit to the building official a written statement that the site visits have been made and identify any reported deficiencies that, to the best of the structural observer’s knowledge, have not been resolved.
[DSA-SS, DSA-SS/CC] Reference to Section 110 shall be to the California Administrative Code instead.
SECTION 1705 A —REQUIRED SPECIAL INSPECTIONS AND TESTS
1705 A .1 General. Special inspections and tests of elements and nonstructural components of buildings and structures shall meet the applicable requirements of this section.
1705 A .1.1 Special cases. Special inspections and tests shall be required for proposed work that is, in the opinion of the building official, unusual in its nature, such as, but not limited to, the following examples:
- Construction materials and systems that are alternatives to materials and systems prescribed by this code.
- Unusual design applications of materials described in this code.
- Materials and systems required to be installed in accordance with additional manufacturer’s instructions that prescribe requirements not contained in this code or in standards referenced by this code.
1705 A .2 Steel construction. The special inspections and nondestructive testing of steel construction in buildings, structures and portions thereof shall be in accordance with this section.
Exception: Special inspections of the steel fabrication process shall not be required where the fabrication process for the entire building or structure does not include any welding, thermal cutting or heating operation of any kind. In such cases, the fabricator shall be required to submit a detailed procedure for material control that demonstrates the fabricator’s ability to maintain suitable records and procedures such that, at any time during the fabrication process, the material specification and grade for the main stress-carrying elements are capable of being determined. Mill test reports shall be identifiable to the main stress-carrying elements where required by the approved construction documents.
1705 A .2.1 Structural steel. Special inspections and nondestructive testing of structural steel elements in buildings, structures and portions thereof shall be in accordance with the quality assurance requirements of AISC 360 and this code.
CMC § 1.8.4.1 High relevance — show source text
**_ 1.8.4.1 Permits. A written construction permit shall be obtained from the enforcing agency prior to the erection, construction, reconstruction, installation, relocation, or alteration of any mechanical system. Exceptions: (1) Work exempt from permits as specified in Chapter 1, Scope and Administration, Division II, Section 104.2 Items (1) through (5) of this code. (2) Changes, alterations, or repairs of a minor nature not affecting structural features, egress, sanitation, safety, or accessibility as determined by the enforcing agency.
(3) Retroactive permits issued in accordance with Health and Safety Code Section 17958.12.
Exemptions from permit requirements shall not be deemed to grant authorization for any work to be done in any manner in violation of other provisions of law or this code. 1.8.4.2 Fees. Subject to other provisions of law, the governing body of any city, county, or city and county may prescribe fees to defray the cost of enforcement of rules and regulations promulgated by the Department of Housing and Community Development. The amount of the fees shall not exceed the amount reasonably neces- sary to administer or process permits, certificates, forms, or other documents, or to defray the costs of enforcement. For additional information, see State Housing Law, Health and Safety Code, Division 13, Part 1.5, Section 17951 and California Code of Regulations, Title 25, Divi- sion 1, Chapter 1, Subchapter 1, Article 3, commencing with Section 6.
1.8.4.3 Plan Review and Time Limitations. Subject to other provisions of law, provisions related to plan checking, prohibition of excessive delays, and contracting with or employment of private parties to perform plan checking are set forth in the State Housing Law, Health and Safety Code Section 17960.1, and for employee housing, in Health and Safety Code Section 17021. 1.8.4.3.1 Retention of Plans. The building depart- ment of every city, county, or city and county shall maintain an official copy, microfilm, or electronic or other type of photographic copy of the plans of every building, during the life of the building, for which the department issued a building permit. Exceptions: (1) Single or multiple dwellings not more than two stories and basement in height. (2) Garages and other structures appurtenant to buildings listed in Exception 1. (3) Farm or ranch buildings appurtenant to build- ings listed in Exception 1. (4) Any one-story building where the span between bearing walls does not exceed 25 feet (7620 mm), except a steel frame or concrete building. All plans for common interest developments as defined in Section 4100 of the California Civil Code shall be retained. For additional information regarding plan retention and reproduction of plans by an enforcing agency, see Health and Safety Code Sections 19850 through 19852. 1.8.4.4 Inspections. Construction or work for which a permit is required shall be subject to inspection by the building official and such construction or work shall remain accessible and exposed for inspection purposes _until approved.
Frequently asked questions
What qualifies as "before piping is covered or concealed"?
Before any permanent covering—drywall, slab backfill, ceiling membranes, insulation or other means that would hide the piping from visual inspection—has been installed. See § 1405.2.1.
Can I backfill an underground trench before inspection?
No. Excavations for underground piping must remain open until piping is inspected and approved; if covered prematurely the AHJ may require exposure. See § 1405.1.
How long must I hold the pressure test?
Test pressure must be held for a period acceptable to the AHJ but not less than 30 minutes with no perceptible drop. See § 1405.2.2.
Who must be present during the pressure test?
The Authority Having Jurisdiction (AHJ) must be present when the tests are made. See § 1405.2.2.
Do I need to bring test equipment?
Yes — the permit holder must furnish necessary apparatus for conducting the tests. See § 1405.2.2.
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