Adopted building code
The 2021 International Residential Code, as adopted by the State in the Pennsylvania Uniform Construction Code (UCC). 34 Pa. Code 403.21(a)(7) adopts "The 'International Residential Code of 2021,' except that:" followed by the State's list of exclusions and modifications, effective January 1, 2026 (55 Pa.B. 7701). None of the State's changes touches Chapter 9, Roof Assemblies, or Section R803, Roof Sheathing, so those apply as the International Code Council publishes them. Work on existing buildings is also pointed to the State's existing-building code: "The repair, alteration, change of occupancy, addition and relocation of existing buildings must comply with Chapter 34 of the 'International Building Code of 2021' or with the 'International Existing Building Code of 2021'" (34 Pa. Code 403.21(f)). The UCC is the minimum everywhere in the state: "no municipality may propose or enact any ordinance which is less than the minimum requirement of the Uniform Construction Code" (Pennsylvania Construction Code Act, Act 45 of 1999, section 503(b)). The Act also lists work it "shall not apply to", including "Alterations to residential buildings which do not make structural changes or changes to means of egress" or to "Repairs to residential buildings," in each case "except as might be required by ordinances" kept in force under section 303(b)(1) or adopted under section 503 (Act 45 section 104(b)(5) and (6); 34 Pa. Code 403.1(b)(8) and (9)). The Act defines a repair as "The reconstruction or renewal of any part of an existing building for the purpose of its maintenance." So whether the code's roofing rules reach a given house reroof depends on the municipality's own ordinances. Everything above is Pennsylvania state law, the same in every municipality. Locally, Morrisville Borough administers the code through a retained agency: Section 129-2 of the Borough Code says the Borough "hereby elects to administer and enforce the provisions of the Pennsylvania Construction Code Act," Section 129-4 lets Borough Council retain "one or more construction code officials or third-party agencies to act on behalf of the Borough of Morrisville," and the Borough's Code Enforcement page names Barry Isett & Associates, Inc., at 484-861-3468, as its contact; permit packets go to the Borough office at 35 Union Street. Section 129-3 adopts the Uniform Construction Code, "as amended from time to time," as the Borough's municipal building code, and Section 129-15 keeps in force building code ordinances adopted on or before July 1, 1999 that equal or exceed the code, without naming them. Article VII of Chapter 129 (Ord. No. 942, June 23, 2004) still names the "International Residential Code, 2003 Edition," while the Borough's current submittal requirements say "Pennsylvania has implemented the ICC 2021 Code series with amendments as voted by the RAC"; this record has not read the 2003 edition's text and does not decide which edition the Borough applies.
Permit process
No Morrisville Borough text read names reroofing as permit work or as exempt. Section 129-20D of the Borough Code says "The Borough shall exempt and not require an owner or authorized agent to obtain a permit to construct, enlarge, alter, repair, move, demolish or change the occupancy of a commercial or residential building, structure or facility" for work "that is identified in Chapter 403.42 (c) or Chapter 403.62 (c) of the Construction Code except that the Borough shall not exempt and shall require a permit for the following:" Its residential list names fences, retaining walls over two feet, sidewalks and driveways, window replacement, garage doors, "Replacement of existing siding," uncovered decks and certain piping; it does not name roofing. Section 129-19B charges a fee "for each and every building within the Borough to be constructed, altered, repaired, or improved," and the fee schedule itself is kept in the Borough offices, not in the code. The Borough's PA UCC Building Permit Application Submittal Requirements (posted September 8, 2026) and its UCC Permit Application name no roof work, and the Code Enforcement page lists no work that needs or does not need a permit. Under state law, Act 45 section 104(b)(5) and (6) list "Alterations to residential buildings which do not make structural changes or changes to means of egress" and "Repairs to residential buildings" among work the Act does not apply to, "except as might be required by ordinances in effect pursuant to section 303(b)(1) or adopted pursuant to section 503," and 34 Pa. Code 403.62(c) says "A permit is not required for the exceptions listed in § 403.1(b) (relating to scope) and the following, if the work does not violate a law or ordinance." Whether Section 129-20D's exemption reaches an ordinary reroof turns on reading the regulation it cites, and neither the Borough's code nor its pages name reroofing as permit work or as exempt, so this record does not decide whether the Borough requires a permit for an ordinary reroof. Ask the Borough's code enforcement contact before work starts. The Borough's submittal requirements say "All documentation must be submitted as a single packet via PDF file(s)," that "Permit packets shall be submitted to the Morrisville Borough office staff for a completion check prior to review," and that all contractors and subcontractors submit an "Annual Contractor Registration Application," a "Copy of active Pennsylvania Home Improvement Contractor (HIC) Registration" and a "Certificate of Insurance naming Morrisville Borough as certificate holder," with property owners working on their own property exempt. The municipal building is open Monday to Friday, 8:00 a.m. to 4:30 p.m., at 215-295-8181. Read for this answer: Chapter 129 of the Borough Code, Building and Construction Codes, in full; Chapter A476, Fees; every page of a search of the whole Borough Code for "roof" and for "reroofing"; the Code Enforcement page; the PA UCC Building Permit Application Submittal Requirements; and the UCC Permit Application. The Borough's fee schedule was not found published online.