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, Whitpain Township administers the code itself: Section 71-1 of the Township Code says "Whitpain Township hereby elects to administer and enforce the provisions of the Pennsylvania Construction Code Act," Section 71-2.2 A provides for "the designation of an employee of the Whitpain Township to serve as the Whitpain Township code official," and the Township's Code Enforcement Department, at 960 Wentz Road, Blue Bell, says its work "includes reviewing applications for permits, examining the accompanying plans and documents, issuing the applicable permit(s), conducting inspections during construction." Section 71-2 of the Township Code incorporates the Uniform Construction Code "as amended from time to time" as the Building Code of Whitpain Township, Section 71-2.1 adds appendixes of the 2003 International codes, and Sections 71-43 and 71-44 still print the "BOCA National Building Code," "being particularly the 1996 Edition thereof," and the CABO One- and Two-Family Dwelling Code, 1995 Edition, with the Township's modifications, while the Township's Building Code page names no edition and says "The Building Code adopted by the Board of Supervisors is the PA.UCC. Act 45, consult PA L&I for the current codes"; this record has not read the 1996 BOCA, 1995 CABO or 2003 editions' text and does not decide which edition the Township applies. Section 71-44's modifications quoted under the repair threshold change the permit section; neither Part 1 nor Part 7 of Chapter 71 changes the code's roofing provisions.
Permit process
Whitpain Township's code requires a permit for construction, alteration or repairs other than ordinary repairs, which it calls nonstructural repairs, and its fee schedule's residential roof replacement line carries the words "(Plywood/Sheathing only)"; whether a covering-only reroof needs a permit is not stated by the Township and is not decided here. Section 71-2.4 A of the Township Code keeps in force building code ordinances adopted on or before July 1, 1999 that "equal or exceed the requirements of the Uniform Construction Code," naming among them "Ordinance No 22-25 enacting the 1996 BOCA National Building Code and the CABO One- and Two-Family Dwelling Code." Section 71-44 B(1) (read October 7, 2026) modifies that CABO code's permit section to read "111.1 Permit required: A permit shall be obtained before beginning construction, alteration or repairs (other than ordinary repairs), using application forms furnished by the Building Official. Ordinary repairs are nonstructural repairs and do not include installation of or modification to plumbing lines, fire protection systems, fuel piping systems, means of egress components, chimneys and flue connectors, fireplaces and/or new air-conditioning and heating units." The same section goes on "A permit shall be required prior to installing or constructing the following accessory structure" and lists, among others, "to install or construct a shed, aboveground or in-ground swimming pool, garage, porch, roof, greenhouse or other accessory structure." The Township's Fee Schedule (Resolution No. 1619, effective January 1, 2026) lists among residential building permits "Roof, Window & Siding Replacement" at $100.00 with the words "(Plywood/Sheathing only)," and a commercial "Roof Covering Replacement" line. The Township has published no statement on whether a covering-only reroof is an ordinary repair, and this record does not decide whether a reroof is an "ordinary repair" under that section, whether the word "roof" in the accessory structure list reaches a reroof, or how the fee line's words limit it. Under state law, Act 45 says the Act "shall not apply to" "Alterations to residential buildings which do not make structural changes or changes to means of egress, except as might be required by ordinances in effect pursuant to section 303(b)(1) or adopted pursuant to section 503" or to "Repairs to residential buildings, except as might be required by ordinances in effect pursuant to section 303(b)(1) or adopted pursuant to section 503" (section 104(b)(5) and (6)), and of a municipal ordinance that adds to the code, section 503(c) says "An ordinance under this subsection shall not be effective nor enforceable unless subsections (d), (e), (f), (g), (h) and (i) have been satisfied." This record does not decide whether the municipality's requirement is one adopted under section 503 or kept in effect by section 303(b)(1). Before starting a reroof, ask the Code Enforcement Department (610-277-2400) whether it treats the job as an ordinary repair. The same modified CABO code says a violator "shall be punishable by a fine of not more than $1,000 for each day that a violation continues after due notice has been served." The Building Code page says "The building inspections required in conjunction with issued building permits can only be scheduled by contacting someone in the Code Enforcement Department" and "The maximum time for residential permit processing is 15 business days from original date of receipt of the application," and the Applications & Forms page links a Building Permit Online Application. Read for this answer: Chapter 71 of the Township Code, Building Construction, Part 1 (Sections 71-1 to 71-2.6), Part 6 (Property Maintenance Code) and Part 7 (Sections 71-43 and 71-44), in full; Chapter 16, Fee Schedule Authorization; a search of the whole Township Code for "roof" and for "reroofing," which found no other permit provision naming roof work; the Code Enforcement, Building Code, Applications & Forms and FAQ pages, which say nothing on roofing; and the Fee Schedule (Resolution No. 1619). The Township Building is at 960 Wentz Road, Blue Bell, phone 610-277-2400.