Pennsylvania Uniform Construction Code (UCC)


Residential Code: The 2009 Uniform Construction Code is based on the 2009 IECC. It also offers alternate compliance paths through the 2009 IRC (Chapter 11) and the 2009 Pennsylvania Alternative Residential Energy Provisions (PA-Alt) (see below). The residential code applies to 1- and 2-family detached homes and townhouses and is mandatory statewide. REScheck may be used to show compliance.

Commercial Code: The 2009 Uniform Construction Code is based on the 2009 IECC with reference to ASHRAE 90.1-2007. The commercial code applies to nonresidential buildings and is mandatory statewide. COMcheck may be used to show compliance.

Code Change Cycle: Generally reviewed every three years with the publication of the new editions of the International Code Council's series of model codes. Most recent code update effective December 31, 2009.

In November 1999, the Pennsylvania Legislature passed Act 45, the Pennsylvania Uniform Construction Code Act of 1999 (since amended in 2004), mandating a statewide building code across Pennsylvania. The legislation requires the Pennsylvania Department of Labor and Industry (DLI) to promulgate regulations to implement the requirements of the legislation and, in addition, to consider the development of alternative prescriptive methods for energy conservation that account for the various climatic regions within the Commonwealth. In deriving these energy standards, the DLI was to seek to balance energy savings with initial construction costs.

The Pennsylvania Housing Research Center (PHRC) developed the Pennsylvania Alternative Residential Energy Provisions (PA-Alt) for consideration by DLI to meet their legislated mandate. The PA-Alt was developed with the intent of being:

  • simpler to build to and easier to enforce;
  • more rational and flexible;
  • focused on Pennsylvania in terms of climatic and other conditions;
  • equivalent to the provisions of the International Energy Conservation Code (IECC).

The PA-Alt is an alternative to Chapter 11 of the International Residential Code (IRC). It is intended to supplement the IRC and, to the extent possible, to be consistent in format and general intent. The scope and definitions used in the IRC apply. It is important to note that a choice needs to be made by the builder or design professional between the PA-Alt, the IRC, and the IECC.

The initial version of the PA-Alt was developed in 2000 and was based on the 2000 IECC and IRC. The second version was updated in 2003 and was based on the 2003 IECC and IRC. The third version was updated in 2006 and was based on the 2006 IECC and IRC. The 2009 PA-Alt is the fourth iteration of the PA-Alt and is equivalent to the 2009 IECC and IRC.

Enforcement of the 2003 UCC began in April 2004. Its successor edition, the 2006 UCC, became effective on December 31, 2006. The current code, the 2009 UCC, became effective December 31, 2009.

In 2011, the Pennsylvania General Assembly passed legislation significantly altering the process to update the state’s construction codes. On January 31, a bill (HB 377) was introduced that would amend the Uniform Construction Code Act of 1999 to require 2/3 approval for any code update proposals by the Department of Labor and Industry (DLI) Review and Advisory Council (RAC). Among other changes, the RAC would be required to submit a report on any proposed changes within 12 months of the official publication of ICC’s triennial code updates. HB 377 also repealed the residential sprinkler provisions of the 2009 IRC and reverted to the 2006 wall bracing requirements.

The bill was approved by the House on March 7. The Senate approved amendments on April 12, and the House concurred April 13. Gov. Tom Corbett signed the legislation in law as Act 1 on April 25. The UCC has been subject to rollback attempts before in both the legislature and state courts.


Over 90% of Pennsylvania's 2,563 municipalities have elected to administer and enforce the UCC locally, using their own employees or via certified third party agencies (private code enforcement agencies) that they have retained. In these municipalities, the Department has no code enforcement authority, except where the municipality lacks the services of a person certified as an "Accessibility Inspector/Plans Examiner."

If a municipality has "opted out," the Department is responsible for all commercial code enforcement in that municipality. The Department also has sole jurisdiction for all elevators and all state-owned buildings, no matter where they are located.

Certified third party agencies hired by property owners (or their contractors) enforce the residential requirements of the UCC in all opt-out municipalities. Detailed information about these agencies and a listing of the choices of the state's municipalities can be accessed at the website of the Department of Labor and Industry.

Back to Pennsylvania

Based on: 
Date Passed: 
Thursday, December 10, 2009
Date Effective: 
Thursday, December 31, 2009
Pennsylvania_Alternative_Residential_Energy_Provisions_2009.pdf1.47 MB
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