2021 IBC Chapter 1
Chapter 1 of the IBC does not tell anyone how to build a wall. It tells everyone who decides, what needs a permit, what has to be drawn, when the building official comes out, and what piece of paper lets people use the building. On a community clinic, a small apartment building, or a church fellowship hall, most of the surprises come from this chapter, not from the structural or fire chapters. This lesson walks a project from application to certificate of occupancy, then covers what happens when something goes wrong.
Section 101 sets the scope: the IBC governs the construction, alteration, repair, and use of buildings and structures. Section 101.4 lists the companion codes, and 101.4.7 sends repair, alteration, change of occupancy, addition, and relocation of existing buildings to the International Existing Building Code. That pointer matters for GCHS, because most rehab work is on existing buildings. This course teaches the new-construction provisions of the IBC; the existing-building code decides how much of them an older building must meet. Section 102.6 adds that the legal occupancy of a structure that existed on the date of adoption may continue without change, except where the codes say otherwise. Chapter 2 holds the definitions, including fire area, occupant load, high-rise building, and change of occupancy.
This course teaches the text of the 2021 IBC. Which edition actually binds a project depends on local adoption. As checked on September 28, 2026: Texas Local Government Code Section 214.216 makes the IBC as it existed on May 1, 2012 the default municipal commercial building code (House Bill 738 of 2021 moved that date forward from May 1, 2003, effective January 1, 2022). That is a floor, and cities may adopt newer editions by ordinance. The City of Houston approved the 2021 I-Codes, with local amendments, on October 25, 2023, effective January 2, 2024. Only projects submitted after that date follow them; earlier applications stay under the 2015 Construction Code. So never say that Texas uses the 2021 IBC. Ask the jurisdiction which edition and which amendments apply. The edition used for the permit is printed on the certificate of occupancy (111.2).
Section 105.1 says an owner or the owner's authorized agent who intends to construct, enlarge, alter, repair, move, demolish, or change the occupancy of a building or structure, or to install regulated electrical, gas, mechanical, or plumbing systems, must first apply to the building official and obtain the permit. Note that changing the occupancy is on the list even when no wall moves. Section 105.2 then lists work exempt from a permit. Its lead-in carries a warning: an exemption is not authorization to violate the code. Local amendments often change the list, so check the adopted version.
Under 105.3.2 an application is deemed abandoned 180 days after filing unless the applicant is pursuing it in good faith or a permit has been issued. The building official may grant extensions of not more than 90 days each, requested in writing with justifiable cause. Once issued, a permit becomes invalid under 105.5 if the work does not commence within 180 days, or if the work is suspended or abandoned for 180 days after it starts. Extensions must be requested in writing, with justifiable cause, and each is limited to 180 days. Temporary structures and uses (Section 108) are allowed for not more than 180 days, with extensions for demonstrated cause.
Worked example. A fellowship hall addition is filed on March 1, 2027 and the design team goes quiet. Counting 180 days gives August 28, 2027, the date the application is deemed abandoned unless it is being pursued in good faith. Suppose the permit is issued September 1, 2027, the foundation starts September 20, and the church stops work on October 15 for lack of funds. Another 180 days gives April 12, 2028. If work is still suspended on that date, the permit is invalid unless a written extension was granted. The official's counting practice governs the exact day, so treat these as planning dates and call early.
Section 107.1 requires construction documents, the statement of special inspections, the geotechnical report, and other data in two or more sets (or digitally where the jurisdiction allows). The documents are prepared by a registered design professional where required by the statutes of the jurisdiction; the IBC itself does not always require one, and the Texas engineering and architectural practice acts decide when a licensed professional is needed. The official may waive submittal where a review is not necessary. Section 107.2 lists what the documents must show, including fire protection shop drawings (107.2.2), the means of egress (107.2.3), the exterior wall envelope (107.2.4), details of the moisture barrier system for exterior balconies and elevated walking surfaces (107.2.5), the site plan (107.2.6), and structural information (107.2.7). Amended documents go back for approval (107.4).
Section 110.1 puts the burden on the owner or agent to keep work visible and accessible until it is approved, and it says that an approved inspection is never approval of a violation. Section 110.2 lets the official examine the site before issuing a permit. Section 110.3 lists twelve inspection items, 110.3.1 through 110.3.12. The permit holder notifies the official when work is ready (110.5), and work may not go past an inspection point without approval; portions that fail must be corrected and stay uncovered until authorized (110.6). The official may accept reports of approved inspection agencies (110.4).
| Inspection | Section | Made when |
|---|---|---|
| Footing and foundation | 110.3.1 | Excavation done, reinforcing and forms in place |
| Slab and under-floor | 110.3.2 | Reinforcing and under-slab services in place, before concrete or floor sheathing |
| Lowest floor elevation | 110.3.3 | Flood hazard areas |
| Frame | 110.3.4 | Roof deck, framing, fireblocking, and bracing in place; rough electrical, plumbing, and mechanical approved |
| Types IV-A, IV-B, IV-C connection protection | 110.3.5 | Wood cover inspected before other coverings (new in 2021) |
| Lath and gypsum board | 110.3.6 | Before plaster or before taping and finishing |
| Balcony and walking surface waterproofing | 110.3.7 | Before the moisture barrier is concealed |
| Fire and smoke penetrations | 110.3.8 | Before they are concealed |
| Energy, other, and special inspections | 110.3.9 to 110.3.11 | As the project requires |
| Final | 110.3.12 | All permit work complete; flood hazard elevation documents in first (110.3.12.1) |
Section 111.1 says no building may be used or occupied, and no change of occupancy made, until the building official issues a certificate of occupancy. Under 111.2 the certificate is issued after an inspection finds no violations, and it lists twelve things: the permit number, the address, the owner's name and address, a description of the portion covered, a statement that it was inspected for compliance, the building official's name, the code edition used for the permit, the use and occupancy group (Chapter 3), the type of construction (Chapter 6), the design occupant load, whether the sprinkler system is required where an automatic sprinkler system is provided, and any special stipulations. That list is a preview of the whole course. A temporary certificate can be issued before all work is done if the occupied portion is safe, and the official sets its time period (111.3). A certificate issued in error, on incorrect information, or in violation of the code can be suspended or revoked in writing (111.4).
Section 114 covers unlawful acts, notices of violation, prosecution, and penalties. Under Section 115 the official may issue a stop work order when work is contrary to the code or dangerous (115.1). It must be in writing, go to the owner, the owner's agent, or the person doing the work, state the reason, and state the conditions for resuming; the cited work stops immediately (115.2). In an emergency no written notice is needed first (115.3). Continuing after service, except work directed to remove the violation or unsafe condition, brings fines (115.4). Section 116.1 deems a structure unsafe for causes such as inadequate means of egress, inadequate light and ventilation, a fire hazard, illegal or improper occupancy, or inadequate maintenance. Related points: the official may enter to inspect at reasonable times after presenting credentials to an occupant and requesting entry, and if entry is refused, uses the remedies provided by law (104.6). Alternative materials and methods must be approved and must be at least equivalent in quality, strength, effectiveness, fire resistance, durability, and safety (104.11). Section 113 provides the means of appeals.
In the field
A nonprofit buys a vacant one-story retail building to turn into a small clinic and wants to "just paint and open." Before pricing anything, ask for the last certificate of occupancy. A shop becoming a clinic is a change of occupancy (Group M to Group B), which needs a permit and a new certificate under 105.1 and 111.1 even with only cosmetic work, and the existing-building code decides what upgrades follow. Then map the inspections: which will you request, and what must stay open until the inspector signs off? A contractor who closes a wall before the frame or penetration inspection has to open it again.
1. A community center wants a detached one-story storage shed under the base 2021 IBC exemption from permit in Section 105.2. What is the largest floor area that stays exempt?
2. A church plans a 6 ft wood privacy fence and, separately, an 8 ft masonry screen fence around a dumpster. Under Section 105.2, which fence is exempt from a permit?
3. A retaining wall shows 3 ft 6 in. of exposed height above grade, and its footing bottom is 12 in. below grade. The wall retains only level soil. Under Section 105.2, is it exempt?
4. A new concrete walkway is 18 in. above adjacent grade, is not over any basement or story below, and is part of an accessible route. Under Section 105.2, the walkway is:
5. A design team submits an application for a Group B office building and does not respond to the plan review comments. Under Section 105.3.2, the application is deemed abandoned after how long, unless it is pursued in good faith?
6. A permit was issued and framing started, but work stopped for funding. Under Section 105.5, the permit becomes invalid if work stays suspended for:
7. Under Section 107.1 of the IBC, construction documents are prepared by a registered design professional:
8. A four-story mass timber office building uses wood cover to provide connection fire-resistance ratings. Which 2021 inspection item applies?
9. An inspector arrives for a frame inspection on a Group M shell. The roof deck and framing are in, but fireblocking is unfinished and the rough plumbing has not been approved. Under Section 110.3.4, the inspector should:
10. Under Section 110.1, who has the duty to keep permitted work visible and accessible for inspection until it is approved?
11. A new Group R-2 building is in a flood hazard area. According to Section 110.3.12.1, what must be submitted before the final inspection?
12. A dental practice will move into a former retail shop. The work is limited to painting and new carpet, but the use changes from Group M to Group B. Under Section 111.1, before the practice opens:
13. A restaurant tenant space has a finished dining room, but the kitchen is still under construction. Under Section 111.3, the building official may:
14. An official finds a serious hazard on a site during an emergency. Under Section 115.3, the official: