Plumbing and HVAC rules in Pennsylvania

Pennsylvania has no state plumbing license. Some municipalities, such as Philadelphia and Allegheny County, license plumbers, and home improvement contractors register with the state Attorney General.^{1, 2, 3}

Pennsylvania's Department of Labor and Industry says the state has no licensing for most construction contractors. Home improvement contractors register with the Attorney General.^{1, 4}

Pennsylvania's Uniform Construction Code uses the 2021 International Plumbing Code, and Philadelphia and Allegheny County run their own plumbing codes.⁵ The Uniform Construction Code uses the 2021 International Mechanical Code for mechanical work.⁵

Pennsylvania's Uniform Construction Code lists replacing mechanical or plumbing systems as work that needs a permit, but it doesn't apply to residential repairs, or to residential alterations without structural or egress changes, unless a local ordinance says so. For a house, it comes down to your municipality.^{6, 7}

If your home has a backflow preventer, your water utility can tell you whether it needs testing and who can test it.