Which Building Code Applies to a Construction Defect Claim?

Permit dates, code transitions, and the existing building code in PA, Philadelphia, NJ, and FL

To decide which building code applies to a construction defect claim, start with the permit. The governing edition is normally the one under which the permit application was reviewed, subject to each state’s transition rules. Alterations to an existing building are evaluated under the existing building code, which also sets when new work must meet the requirements for new construction.

The “code of record” is the specific code edition, with local amendments, under which a project was permitted and approved.

Load requirements and referenced standards change between editions, so identifying the code of record helps a forensic engineer compare the work with the requirements that applied to it..

Which building code applies in PA, Philadelphia, NJ, and Florida?

Pennsylvania and Philadelphia

Section 304(c)(4) of Pennsylvania’s Uniform Construction Code allows a permit under the code in effect when a design or construction contract was signed. The application must be filed within six months of the new code’s effective date.

Philadelphia’s Code Bulletin B-2501 adds two rules. Amendments to an issued permit are reviewed under the original permit’s edition. An expired permit that is resubmitted falls under the 2021 codes.

New Jersey

New Jersey adopted the 2024 I-Codes in rule R.2026 d.086. Under N.J.A.C. 5:23-1.6, for six months after a subcode revision’s operative date, a complete application may be reviewed under the preceding code. An issued permit generally continues under its edition while it stays valid.

Florida

The Florida Building Code, Existing Building, often called the Florida Existing Building Code, governs work in existing structures. The Florida Building Commission’s October 2026 workplan lists a 9th Edition effective date of December 31, 2026. Its final rule hearing is still marked “TBD..”

What records establish the code of record?

• The permit application date and, in Pennsylvania, the design or construction contract date
• Approved permit drawings and plan review comments
• The code edition stated in the drawings’ code summary or general notes
• Inspection records and the certificate of occupancy
• Later alteration, addition, or change-of-occupancy permits
• Permit amendments, renewals, or reinstatements

The filing date is then compared with the jurisdiction’s transition rule. A code evaluation can document any conflict in the records and the evidence on each side.

How do later alterations change which code governs?

A building can carry several codes of record. The original structure follows one edition. A later alteration follows the edition in force when its own permit was reviewed.

For Pennsylvania and Philadelphia permits under the 2021 codes, commercial and multifamily alterations follow the 2021 International Existing Building Code (IEBC). Under Section 301.3, the applicant selects one method: prescriptive (Chapter 5), work area (Chapters 6 through 12), or performance (Chapter 13). The work area method defines Level 1, 2, and 3 alterations in Sections 602 through 604 and treats additions and change of occupancy separately.

Commercial examples

Rooftop mechanical units or a solar array add gravity load to an existing roof, which makes the work an alteration. Under the prescriptive method, 2021 IEBC Section 503.3 sets a 5 percent threshold for existing gravity elements. Above that increase in design gravity load, the element generally must carry the loads the IBC requires for new structures.

Whether a given element crosses the threshold is a calculation for that element, under the governing edition and any local amendments.

A change in use that raises the required floor live load, such as office space converted to file storage, can be a change of occupancy under IEBC Chapter 10. Section 1006.1 requires elements carrying live load from the changed area to meet IBC Section 1607 for the new use. An exception applies where the element’s demand-capacity ratio rises 5 percent or less.

How is the work compared with the governing edition?

Provisions are compared in the edition that governed the work, which may differ from the current one. A code evaluation can identify the edition, local amendments, documents relied on, and any gaps in the permit file.

For attorneys: what to request early

Request before site work:

• The full municipal permit file, including the application date
• Approved permit drawings, plus bid and construction sets and all revisions
• All later permits for the property
• Correspondence on which code edition the applicant elected

A litigation support engineer can review that file for gaps. The same method applies to commercial buildings and houses and multifamily buildings.

Frequently asked questions

Does today’s code apply to an older building?

Usually the original permit’s edition governs the original construction. Under Section 302.3 of the 2021 International Existing Building Code, materials that complied when installed may remain in use unless the code official finds them unsafe. New work follows the code in force when that work was permitted, which may be a newer edition.

What if the drawings do not state a code edition?

The permit application date and the jurisdiction’s adoption records can point to the edition. The edition in force on the filing date, adjusted for any transition or grace period, is the usual starting point, and plan review comments may confirm it.

Does an expired or resubmitted permit change the governing code?

It can in Philadelphia and New Jersey. Philadelphia Code Bulletin B-2501 states that an expired permit resubmitted for review is subject to the 2021 codes. In New Jersey, an expired permit or resubmitted project may have to meet the edition in effect at the new application or reinstatement, so both dates matter.

Which code governs work on an existing building in New Jersey?

New Jersey uses its Rehabilitation Subcode, N.J.A.C. 5:23-6, instead of the IEBC. It sorts work into six categories, from repair through addition, and additions must meet the other technical subcodes. Rule R.2026 d.086 did not amend the Rehabilitation Subcode, but those other subcodes now adopt the 2024 I-Codes.

Talk with a construction defect expert: New Jersey, Pennsylvania, and Florida

Penn Valley Engineering, LLC was founded in 2005 by Gregory S. Baker, P.E., licensed in Pennsylvania, New Jersey, Delaware, Maryland, and Florida. He has served as an engineering expert in the New Jersey Superior Court and Pennsylvania courts. He provides construction defect expert witness services.

Call South Jersey (Cinnaminson) at (856) 872-3537, Philadelphia at (215) 821-7686, or Central Florida (Brevard County) at (321) 394-8026. Email info@pennvalleyengineering.com or use our contact form.

This article is general information, not legal advice. Code requirements change, and local amendments vary. Confirm the applicable code with the authority having jurisdiction.

Sources

• City of Philadelphia, Code Bulletin B-2501, Implementation of 2021 International Codes (Oct. 20, 2025)
• Jensen Hughes, Pennsylvania Adopts 2021 I-Codes into the UCC
• City of York, PA, 2021 UCC Code Update and Implementation
• N.J. Department of Community Affairs, Adoption of 2024 Model Codes, R.2026 d.086
• N.J.A.C. 5:23-1.6
• N.J.A.C. 5:23-6.1, Rehabilitation Subcode
• Jensen Hughes, New Jersey Uniform Construction Code Update (Aug. 25, 2026)
• Alachua County, FL, Florida Building Codes
• Florida Building Commission, Workplan, October 2026
• ICC, 2021 International Existing Building Code, Chapter 3 (Sections 301.3, 302.3)
• ICC, 2021 IEBC, Chapter 5, Prescriptive Compliance Method (Section 503.3)
• ICC, 2021 IEBC, Chapter 6, Classification of Work (Sections 602 to 604)
• ICC, 2021 IEBC, Chapter 10, Change of Occupancy (Section 1006.1)
• City of Philadelphia, 2021 IEBC Significant Changes FAQ
• City of Houston, 2021 IEBC overview (Section 101.2 scope exception)
• Kirk Wagner, S.E., “The Basics of the 5% Rule,” STRUCTURE magazine (2018 IEBC)

By Gregory S. Baker, P.E. | As of October 22, 2026