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, South Heidelberg Township administers the code through Kraft Municipal Group: the Township's Building/Permitting page says "Kraft Code Services is appointed by the Board of Supervisors to act as the Township's Building and Codes Officer" and gives Kraft Municipal Group, "Zoning Office/Building Inspections/Uniform Construction Code Enforcement," at 6525 Shillington Plaza, Shillington, and Kraft Municipal Group lists South Heidelberg Township among the municipalities it serves. Applications are dropped off and permits picked up at the Township Building, 555A Mountain Home Road, Sinking Spring. Chapter 178 of the Township Code (Ord. No. 189, June 24, 2004) adopts the Uniform Construction Code "as amended from time to time, as the municipal building code of this Township" and says "this section shall apply to all construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal, demolition of every building and/or structure occurring in the Township of South Heidelberg on or after July 1, 2004"; it names no roof work, and a search of the whole Township Code for "roof" and for "reroofing" found no section that requires or exempts a permit for roof work. Section 178-2L fills in Table R301.2(1), including "Ice shield underlayment required: Yes"; Chapter 178 changes nothing in the code's roofing provisions and names no code edition, and the Township's and the agency's pages name none for houses.
Permit process
The Township's own permit statements point two ways on roofing. The Township's Activities Requiring a Permit page (read October 9, 2026) lists "Roofing (structural repairs)" among "Construction activities requiring permits from the Building Department" and says nothing else on roofing. The Repair / Replacement Permit Application the Township posts on its Applying for a Permit page (dated 1/15/10) lists, under "Type of Repair/Replacement," "Non-structural Re-roofing (>25% of roof area)." Kraft Municipal Group's current permit application says building approval will be required where the project includes "the construction, enlargement, alteration, structural repair, relocation, or demolition of a building." Chapter 178 of the Township Code (Ord. No. 189, June 24, 2004) adopts the Uniform Construction Code "as amended from time to time, as the municipal building code of this Township" and says "this section shall apply to all construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal, demolition of every building and/or structure occurring in the Township of South Heidelberg on or after July 1, 2004"; it names no roof work, and a search of the whole Township Code for "roof" and for "reroofing" found no section that requires or exempts a permit for roof work. 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." One Township page limits roofing to structural repairs and a posted Township application lists non-structural re-roofing of more than 25% of the roof, so this record does not decide whether the Township requires a permit for an ordinary reroof. Ask Kraft Municipal Group at 610-775-7185 before work starts. The Repair / Replacement packet says "No construction may begin without paying for and receiving your approved permit. Performing work without a permit will result in the doubling of all permit fees," asks for proof of the contractor's workers' compensation insurance or a notarized exemption form, and gives the Building Inspector 3 weeks to review a residential application. A non-refundable residential application fee is due at drop-off at the Township Building, 555A Mountain Home Road, Sinking Spring, open 8:00AM to 5:00PM Monday thru Friday; checks are payable to South Heidelberg Township. Read for this answer: Chapter 178 of the Township Code, Construction Codes, Uniform (Sections 178-1 to 178-8), in full; Chapter 231, Fees, in full, which carries no building permit fees; every page of a search of the whole Township Code for "roof" and for "reroofing"; the Township's Building/Permitting, Activities Requiring a Permit and Applying for a Permit pages, its Building Permit and Repair / Replacement Permit packets; and Kraft Municipal Group's municipality list, its 2026 General Information sheet for South Heidelberg Township and its current permit application. No Township building fee schedule is published on the Township's site.