CMC · California Mechanical Code
Administration & Permits
This hub summarizes the CMC’s permit, fee, plan‑review, inspection and enforcement framework (see §1.8.4 and the administration chapters).
Last reviewed: July 6, 2026
Overview
This area of the California Mechanical Code (CMC) covers the procedural rules that govern permits, fees, plan review, inspections and enforcement for mechanical work in California. The CMC makes clear that a written construction permit is required before erection, installation, alteration, relocation or reconstruction of mechanical systems, and it establishes exceptions, retroactive‑permit rules, and limits on exemptions. See §1.8.4.1 for permits, §1.8.4.2 for fees, and §1.8.4.3 for plan‑review and retention requirements.
Why it matters: these provisions set who must apply, what documents are required, what work may be exempt, how fees are set, and the framework for inspections and enforcement — all essential for compliance, permitting timelines, and avoiding stop‑work or retrofit requirements. The CMC’s administrative rules sit alongside the broader Division II administration and enforcement chapters (for example, construction documents §106, fees §108, inspections §109, certificate of occupancy §110 and means of appeal §112) that shape local plan‑check and inspection workflows.
In this section
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 04-15 Medium relevance — show source text
. . . . . . . . . 063928
Table 1 Description of Items to be Furnished and Installed by Customer Item Description 1 Option 1: Meter Adapter, Cooper B-Line Cat. No. MARR20L45GRSD
(160A) Use with Customer’s Panel Rated at 160A Continuous1, 21 Option 2: Meter Adapter, Ekstrom Industries No. 722B (175A). Specify Left, Right, or Bottom Hub 2 Combination Service Meter and Breaker Panel (rating as required) 3 Pull Termination Box, 8” x 12” x 4”, Rain-Tight, Circle A-W (Cooper B-Line) No. R-9007A or Equivalent (see Note
4M on Page 2)4 Conduit, See Notes 4C and 4G on Page 1 5 Hub to Be Closed and Made Tamper Proof 6 Pull Termination Box, 12” x 26” x 6”, Rain-Tight, Circle A-W Catalog Number R-90008, or Equivalent
(see Note 4K on Page 2)1 Fifth jaw accessory, use Cooper B-Line Cat. No. 50365. 2 Reducer hub and gasket accessories for 2” conduit, use Cooper B-Line Cat. No. AW200 and 12750A.
061032 Page 2 of 4 Rev. #04: 04-15-11
UG-1: Services Greenbook Residential and Small Commercial Overhead to Underground Electric Service Conversion
Optional Removable by Customer
To Be Removed
by PG&E
Meter Socket (see Figure 2 through Figure 7 on Pages 3 through 4)
For Riser and Pull Box Detail (see Figure 2 through Figure 7 on Pages 3 through 4)
For Gas and Water Sealing Requirements,
see Documents 063927 and Document 063928
48” Min.
72” Max.
Customer Shall Dig and Backfill Trench
(see Note 4B on Page 1)
Min. Bend
Depth
To PG&E Distribution System
As required byCol2 Col3 Customer Shall Dig and Backfill Trench
(see Note 4B on Page 1)
For Riser and Pull Box Detail (see Figure 2 through Figure 7 on Pages 3 through 4)
Meter Socket (see Figure 2 through Figure 7 on Pages 3 through 4)
To Be Removed
by PG&E
For Gas and Water Sealing Requirements,
seeDocuments 063927 andDocument 063928
To PG&E Distribution System
Optional Removable by Customer
48” Min.
72” Max.
As required by
Min. Bend
DepthDocument 063927 and Document 063928
Figure 1 Typical Service Conversion
PG&E Service Termination Point
See Note 4K on Page 2
PG&E Service Termination Point (see Note 4L on Page 2)
CMC § 1-12 Medium relevance — show source text
1.9 Division of the State Architect . . . . . . . . . . . . . . . . . . . . 1-12
1.10 Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-15
1.12 State Librarian. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
1.13 Department of Water Resources . . . . . . . . . . . . . . . . . . 1-20
1.14 California State Lands Commission . . . . . . . . . . . . . . . 1-20
DIVISION II – SCOPE AND ADMINISTRATION . . . . . . . . . . . . . . . . . 1-21
PART 1—SCOPE AND APPLICATION. . . . . . . . . . . . . . . . . . . . . . . 1-21
101 Scope and General Requirements. . . . . . . . . . . . . . . 1-21
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-22
PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-22
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-22
104 Duties and Powers of Code Official. . . . . . . . . . . . . . 1-22
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
106 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-26
107 Temporary Uses, Equipment and Systems. . . . . . . 1-28
108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28
109 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28
110 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-30
111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30
112 Means of Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30
CMC § 2.3 Medium relevance — show source text
**_ Refer to the Special Occupancy Parks Act, California Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000 for special occupancy park administra- tive and enforcement authority, permits, fees, viola- tions, inspections, and penalties both within and outside of special occupancy parks. Exception: Special occupancy parks where the Department of Housing and Community Develop- ment is the enforcing agency. 1.8.3.2.4 Employee Housing Act. Refer to the Employee Housing Act, California Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600 for employee housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.3.2.5 Factory-Built Housing Law. Refer to the Factory-Built Housing Law, California Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000 for factory-built housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.4 Permits, Fees, Applications, and Inspections. 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.
CMC § 7.5 Medium relevance — show source text
7.5|Fees|N||||||||| |104.8|Liability|Y||||||||| |104.8.1|Legal defense|Y||||||||| |104.9|Approved materials
and equipment|N||||||||| |104.9.1|Material and
equipment reuse|N||||||||| |104.10|Other agencies|N||||||||| |105|Permits|Y||||||||| |105.1|General|Y||||||||| |105.2|Permits required|Y||||||||| |105.3|Work exempt from
permit|Y||||||||| |105.4|Permit application|Y||||||||| |105.4.1|Preliminary
inspection|N||||||||| |105.4.2|Time limitation of
application|N||||||||| |105.5|Permit approval|N||||||||| |105.6|Permit issuance|N||||||||| |105.6.1|Refusal to issue a
permit|N||||||||| |105.7|Validity of permit|N||||||||| |105.8|Expiration|Y||105.5.1||||||| |105.9|Retention of permits|N|||||||||APPENDIX H-22 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
APPENDIX H—REFERENCED CALIFORNIA DOCUMENTS
2025 CWUIC—continued Col2 Adopted
Yes/NoIWUIC
SectionCBC
SectionCFC
SectionTitle 14,
Division 1.5
SectionTitle 19,
Division 1
SectionGov Code
SectionPRC
SectionHSC
SectionSection Title Title Title Title Title Title Title Title Title Title Chapter 1 _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration _Division II—_Scope and Administration 105.10 Revocation of permits Y 106 Construction
documentsY 106.1 General Y 107.1 106.2 Information on plans
and specificationsY 106.3 Site plan Y 106.4 Vegetation manage-
ment_compliance_Y 701A.5 106.5 Fire protection plan Y 106.6 Other data and
substantiationN 106.7 Vicinity plan Y 106.8 Retention of plans Y 1.11.3.5 106.9 Examination of
documentsN 106. CMC § 04-15 Medium relevance — show source text
. . . . . . . . . . . . . . . . . . . UG-1: Services/Greenbook . . . . . . . . . . . . . . . . . . 063927 Methods and Requirements for Installing Commercial Underground Electric Services 0−600 Volts to Customer-Owned Facilities . . . . . . . . . . . . . . . . . . . . UG-1: Services/Greenbook . . . . . . . . . . . . . . . . . . 063928
Table 1 Description of Items to be Furnished and Installed by Customer Item Description 1 Option 1: Meter Adapter, Cooper B-Line Cat. No. MARR20L45GRSD
(160A) Use with Customer’s Panel Rated at 160A Continuous1, 21 Option 2: Meter Adapter, Ekstrom Industries No. 722B (175A). Specify Left, Right, or Bottom Hub 2 Combination Service Meter and Breaker Panel (rating as required) 3 Pull Termination Box, 8” x 12” x 4”, Rain-Tight, Circle A-W (Cooper B-Line) No. R-9007A or Equivalent (see Note
4M on Page 2)4 Conduit, See Notes 4C and 4G on Page 1 5 Hub to Be Closed and Made Tamper Proof 6 Pull Termination Box, 12” x 26” x 6”, Rain-Tight, Circle A-W Catalog Number R-90008, or Equivalent
(see Note 4K on Page 2)1 Fifth jaw accessory, use Cooper B-Line Cat. No. 50365. 2 Reducer hub and gasket accessories for 2” conduit, use Cooper B-Line Cat. No. AW200 and 12750A.
061032 Page 2 of 4 Rev. #04: 04-15-11
UG-1: Services Greenbook Residential and Small Commercial Overhead to Underground Electric Service Conversion
CMC § 1-22 Medium relevance — show source text
PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-22
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-22
104 Duties and Powers of Code Official. . . . . . . . . . . . . . 1-22
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
106 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-26
107 Temporary Uses, Equipment and Systems. . . . . . . 1-28
108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28
109 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28
110 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-30
111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30
112 Means of Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30
113 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
114 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
115 Unsafe Structures and Equipment . . . . . . . . . . . . . . 1-31
116 Emergency Measures . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32
117 Demolition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32
CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
202 General Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
CHAPTER 3 PROVISIONS FOR ALL COMPLIANCE
METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3
301 Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
CMC § 1-24 Medium relevance — show source text
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-24
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-24
104 Duties and Powers of Building Official. . . . . . . . . . . 1-25
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
106 Floor and Roof Design Loads . . . . . . . . . . . . . . . . . . . 1-29
107 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-29
108 Temporary Structures, Equipment and Systems . . . . . . . . . . . . . . . . . . . . . 1-31
109 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
110 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
111 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-33
112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
113 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
114 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
115 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
CHAPTER 3 OCCUPANCY CLASSIFICATION AND USE . . . . .3-1
301 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
302 Occupancy Classification and Use Designation . . . . 3-3
CMC § 1-4 Medium relevance — show source text
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-4
1.12 Board of Forestry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
DIVISION II SCOPE AND ADMINISTRATION . . . . . . . . . . . . . 1-15
PART 1—GENERAL PROVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
101 Scope and General Requirements. . . . . . . . . . . . . . 1-15
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-17
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . 1-17
104 Duties and Powers of the Code Official . . . . . . . . . 1-17
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19
106 Construction Documents . . . . . . . . . . . . . . . . . . . . . 1-20
107 Temporary Uses, Equipment and Systems . . . . . . 1-21
108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21
109 Inspection and Enforcement . . . . . . . . . . . . . . . . . . 1-22
110 Certificate of Completion . . . . . . . . . . . . . . . . . . . . . 1-24
111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
112 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
113 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
CHAPTER 3 WILDLAND-URBAN INTERFACE AREAS . . . . 3-3
CMC § 8.10 Medium relevance — show source text
1.8.10 Other Building Regulations . . . . . . . . . . . . . . . . . . . . . . 1-13
1.9 Division of the State Architect . . . . . . . . . . . . . . . . . . . . 1-13
1.10 Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-17
1.12 State Librarian. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-22
1.13 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-22
1.14 California State Lands Commission . . . . . . . . . . . . . . . 1-22
DIVISION II – SCOPE AND ADMINISTRATION . . . . . . . . . . . . 1-23
Part 1—Scope and Application. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
101 Scope and General Requirements. . . . . . . . . . . . . . . 1-23
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-24
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-24
104 Duties and Powers of Building Official. . . . . . . . . . . 1-25
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
106 Floor and Roof Design Loads . . . . . . . . . . . . . . . . . . . 1-29
107 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-29
108 Temporary Structures, Equipment and Systems . . . . . . . . . . . . . . . . . . . . . 1-31
109 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
110 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
111 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-33
CMC § 1.8.4 Medium relevance — show source text
SECTION 1.8.4—PERMITS, FEES, APPLICATIONS AND INSPECTIONS
1.8.4.1 Permits. A written construction permit shall be obtained from the enforcing agency prior to the erection, construction, reconstruction, installation, moving or alteration of any building or structure.
Exceptions:
1. Work exempt from permits as specified in Chapter 1, Division II, Scope and Administration, Section 105.2. 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 necessary to administer or process permits, certificates, forms or other documents, or to defray the costs of enforcement. For additional information, see the State Housing Law, Health and Safety Code, Division 13, Part 1.5, Section 17951 and California Code of Regulations, Title 25, Division 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 department of every city, county, or city and county shall maintain an official copy, microfilm, 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 buildings 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.
CMC § 9-11 Medium relevance — show source text
9”||||||Col1 Col2 Col3 /8” /8” /8” 8” 8” 9/16”
Bus Drilling Detail
Figure 9-11 Bused CT Cabinet (4-Wire Service, 400 Amps Max)
9-9 2022 – 2023
Section 9, Electric Metering: Components and Cable Terminating Facilities
9.9. Meter Box for Transformer-Rated Metering
Applicants must ensure that meter socket jaw requirements and connections are made according to the rules in Section 5, “Electric Metering: General,” Subsection 5.6., “Meter Types and Connections,” on Page 5-26.
Horizontal Lay-In Bonding Lug With #8 Min. Wire Capacity
3/4” Wire Pulling Space
Caution Sign “DO NOT BREAK SEALS,
NO FUSES INSIDE”
Hub 12” Min. 12” Min. Col3 Hub Col5 Col6 Front Seal
ALS,
E”
Hub
3”
3”
1-3/4” Max.
5”
See Note 1
9”
2
11”Hub Hub Hub Front Seal
ALS,
E”
Hub
3”
3”
1-3/4” Max.
5”
See Note 1
9”
2
11”9”
2
1”Front Seal
ALS,
E”
Hub
3”
3”
1-3/4” Max.
5”
See Note 1
9”
2
11”Front Seal
ALS,
E”
Hub
3”
3”
1-3/4” Max.
5”
See Note 1
9”
2
11”Front Seal
ALS,
E”
Hub
3”
3”
1-3/4” Max.
5”
See Note 1
9”
2
11”See Note 1 See Note 1 Front Seal
ALS,
E”
Hub
3”
3”
1-3/4” Max.
5”
See Note 1
9”
2
11”1-3/4” 1-3/4” Max. Max. Max. 2 K.O. (See Note 2)
4-1/2”
CMC § 4.00 Medium relevance — show source text
10
wood screw|1|24|4.00|0.90|DR|DR|2.85|DR|DR|DR| |Minimum 1x
Wood Furringd|Minimum 2x
Wood Stud|1/4" lag screw|11/2|12|4.00|2.65|1.50|0.90|4.00|1.65|0.80|DR| |Minimum 1x
Wood Furringd|Minimum 2x
Wood Stud|1/4" lag screw|11/2|16|4.00|1.95|0.95|0.50|4.00|1.10|DR|DR| |Minimum 1x
Wood Furringd|Minimum 2x
Wood Stud|1/4" lag screw|11/2|24|4.00|1.10|DR|DR|3.25|0.50|DR|DR| |For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
DR = Design Required, o.c. = on center.
a. Wood framing and furring shall be spruce-pine-fir or any wood species with a specific gravity of 0.42 or greater in accordance with ANSI/AWC NDS.
b. Nail fasteners shall comply with ASTM F1667, except nail length shall be permitted to exceed ASTM F1667 standard lengths.
c. The thickness of wood structural panels complying with the specific gravity requirements of Note a shall be permitted to be included in satisfying the minimum required
penetration into framing.
d. Where the required cladding fastener penetration into wood material exceeds3/4 inch and is not more than 11/2 inches, a minimum 2-inch nominal wood furring or an
approved design shall be used.
e. Foam sheathing shall have a minimum compressive strength of 15 psi in accordance with ASTM C578 or ASTM C1289.
f. Furring shall be spaced not greater than 24 inches on center in a vertical or horizontal orientation. In a vertical orientation, furring shall be located over wall studs and attached with
the required fastener spacing. In a horizontal orientation, the indicated 8-inch and 12-inch fastener spacing in furring shall be achieved by use of two fasteners into studs at 16 inches
and 24 inches on center, respectively.|For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
DR = Design Required, o.c. = on center.
a. Wood framing and furring shall be spruce-pine-fir or any wood species with a specific gravity of 0.42 or greater in accordance with ANSI/AWC NDS.
b. Nail fasteners shall comply with ASTM F1667, except nail length shall be permitted to exceed ASTM F1667 standard lengths.
c. The thickness of wood structural panels complying with the specific gravity requirements of Note a shall be permitted to be included in satisfying the minimum required
penetration into framing.
d. Where the required cladding fastener penetration into wood material exceeds3/4 inch and is not more than 11/2 inches, a minimum 2-inch nominal wood furring or an
approved design shall be used.
e.
Frequently asked questions
When is a mechanical permit required?
A written construction permit must be obtained before erection, installation, relocation, alteration, or reconstruction of any mechanical system, except for specific minor exemptions listed in the code or retroactive permits authorized by statute. See §1.8.4.1 for the permit requirement and its exceptions.
How are permit fees and plan review handled?
Fees may be imposed to defray enforcement and processing costs but cannot exceed amounts reasonably necessary; plan review procedures and time limits are addressed in the code’s plan‑review provisions. See §1.8.4.2 (fees) and §1.8.4.3 (plan review/retention).
Where do inspections, certificates and appeals fit in?
Inspections, certificates of occupancy/completion, and appeal mechanisms are governed by the administration and enforcement chapters that work with the CMC permitting provisions — see the administration chapter listings (e.g., §§106, 108–110, 112) for how documents, fees, inspections and appeals are organized.
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