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, Bedminster Township, in Bucks County, issues permits through its Land and Municipal Office at 432 Elephant Road, Perkasie, and its Building and Zoning page names "Building Code Official: Keystone Municipal Services" and says "Inspections are handled by Keystone Municipal Services and are scheduled through the Township office at 215-249-3320." The Building and Zoning page says "Residential plans must comply with the 2021 IRC (International Residential Code)." The Township's building chapter, Chapter 95 of the Township Code (Building Regulations, with sections titled "Pennsylvania Construction Code Act," "Uniform Construction Code," "BOCA Basic National Plumbing Code" and "BOCA Basic National Building Code"), is published online but its section text could not be opened for this record, so the Township's enacted permit rules were not read.
Permit process
Bedminster Township's permit FAQ says "Starting October 22, 2014, permits are no longer required for roof replacement on residential structures, as long as there are no structural repairs involved." The Township's Frequently Asked Questions page, under "What projects require a permit?", says "Starting October 22, 2014, permits are no longer required for roof replacement on residential structures, as long as there are no structural repairs involved," and lists "roof replacement for commerical buildings" among work that needs a building permit. The same page says "Most of all activites require a permit" and "If you should not see a certain example, please contact the building/zoning office at 215-249-3320 to question whether a permit is required," and the Building and Zoning page says "A building permit is required for all construction." The 2022 fee schedule (Resolution No. 2022-05) has no roofing line. The Township's building chapter, Chapter 95 of the Township Code (Building Regulations, with sections titled "Pennsylvania Construction Code Act," "Uniform Construction Code," "BOCA Basic National Plumbing Code" and "BOCA Basic National Building Code"), is published online but its section text could not be opened for this record, so the Township's enacted permit rules were not read. 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." Because the Township's own building chapter was not read, this record does not decide whether an ordinary residential reroof needs a permit; the Township's stated practice is the no-permit line quoted above. For work that does need a permit, the fee schedule says that if construction begins "without receiving the required permits, the permit fee shall be 200% of the applicable permit fee." The Land and Municipal Office is open Monday to Friday, 8 a.m. to 4 p.m., at 215-249-3320. Read for this answer: the Township's Building and Zoning, Frequently Asked Questions, Building Permit Guidelines and fee schedule pages; the 2022 fee schedule, all 12 pages (a scanned document, transcribed from the rendered page images); and the table of contents of Chapter 95 of the Township Code.