Wisconsin Building Energy Codes

Code Level

2009 IECC Model Residential Code vs. Wisconsin's 2009 IECC Amendments

Requirement 2009 IECC Model Code WI 2009 IECC Amendments
Tables 322.31-1, 322.31-2 & 322.31-4
Window Fenestration U-factor: 0.35 Two additional prescriptive compliance options were created*
Wood Frame Wall Insulation

R-value: 20 or 13+5 (CZ 6) 21 (CZ 7)

R-value: 21/19+5 


R-value: 20 or 13+5 (CZ 6) R-value: 21 (CZ 7) *

Basement/Foundation Wall Insulation R-value: 15/19
U-factor: 0.050

R-value: 15/19
U-factor: 0.045


R-value: 15/19
U-factor: 0.050 *

*Use of this value for compliance requires installation of efficient heating equipment see the list of detailed code changes



Authorized by – Statute. The commercial building energy code is authorized by Wisconsin Statutes 101.027 where it lists requirements for rule promulgation, department oversight, and code updates. The residential energy code is authorized by Wisc Stat 101.62 through powers granted to the Uniform Dwelling Code Council.

Oversight – Previously under the Department of Commerce, as of 2012 all building codes oversight and regulation has been moved to the Department of Safety and Professional Services, along with renumbering of all regulations (e.g. the residential energy code was COMM 22, and is now SPS 322). 

Code change process – Regulatory and Legislative. The Office of Codes and Applications in the Department of Safety & Professional Services reviews, proposes and approves code changes after a public comment process. Adopted code changes are then approved by legislative committee. As of amendments implemented in Wisconsin's 2011 fiscal budget, all code changes to the Universal Dwelling Code that would increase the cost of the home by more than $1000 are required to go through a full legislative process for approval (Wisc Stat 227.137(3)(f)).

Code change cycle - Every three years for commercial (Wisc Stat 101.027(3)(a)2), concurrent with updates to the model energy code. The energy code for residential buildings does not have a set update cycle.


Enforcement – SPS Chapters 363 and 367 (commercial and rental buildings) requirements may be changed by local governments or agencies by ordinance only if the alternatives are as stringent as those in the referenced code. SPS Chapter 322 requirements must be applied without local modification. Code inspections are performed by local code officials, and if the local jurisdiction does not have code enforcement then by the Department of Safety & Professional Services (for commercial buildings) or by an agency or delegate approved by the Department (for residential buildings). Enforcement powers lie with the Department of Safety & Professional Standards.

Implementation/Compliance Studies – Wisconsin completed a commercial code compliance study in 2011.

Primary Contacts

Wisconsin Department of Safety and Professional Services

Wisconsin Code Officials Alliance

Building Inspectors Association, Southeast Wisconsin Region