One- & Two-Family (Uniform Dwelling Code)

​​The Uniform Dwelling Code (UDC) is the statewide building code for one- and two-family dwellings built since June 1, 1980. The Division of Industry Services (DIS) provides consultation and education concerning UDC construction standards and inspection procedures. Building materials are evaluated for conformance with standards. UDC inspection and contractor credentials are administered. The UDC is enforced in all Wisconsin municipalities.

Questions regarding the Uniform Dwelling Code can be sent to

Wis. Admin. Code §SPS 327 describes standards for the construction and inspection of camping units. Go to the Camping Units program page for more information.​


2024 Winter Inspector Code Updates
Wisconsin’s regional inspector associations, in cooperation with the Wisconsin Code Officials Alliance and the Wisconsin Department of Safety & Professional Services, are offering virtual and in-person training sessions in early 2024 for Wisconsin’s Electrical Code, Uniform Dwelling Code, Plumbing Code, and Commercial Building Code.  These courses can provide continuing education credits for Industry Services inspection and Dwelling Contractor Qualifier (DCQ) credentials.  Fire inspectors, designers, contractors, and others with an interest in Wisconsin’s codes may also benefit from the programs.

Recall Alert: Schneider Electr​ic Square D QO™ Plug-On-Neutral Load Center

Schneider Electric has issued a product recall on specific models of the Square D QO™ Plug-On-Neutral Load Center (also known as a breaker box or electrical panel). Visit Schneider Electric online at for more information.

Any recalled models previously installed within the state of Wisconsin will be flagged during inspection and may require replacement before the inspection is approved.

​ ​

​​eSLA Instructions For Permit Requestors

How to File for a UDC Permit, including FAQs

eSLA Instructions For Municipalities

UDC Permits in eSLA FAQs (Options 1, 2, and 3)

Uploading CSV Files of UDC Permit Data to eSLA (Option 2)

API Guidance Document (Option 3)

Municipality Training Videos

UDC Permit Tabulation (By County)

Act 211 requires the department to have a standard electronic building permit form (SBD-5823) available to municipalities by January 2, 2017. This permit form shall require contractor license numbers and the expiration dates of their licenses. It also requires municipalities or their agents to provide their permit forms electronically to DSPS through our approved electronic system by January 2, 2018. These permits must be submitted to DSPS by the 15th of the first month after it is issued. If a municipality fails to submit the permit by the required time after the permit was issued, a refund of the amount paid for the building permit minus the state seal shall be given to the permit applicant.

To ensure compliance with Act 211, municipalities must contact DSPS UDC staff to obtain an access code and choose the method by which they will submit information to the DSPS. All municipalities must begin supplying their new one- and two- family dwelling permit information to the DSPS by January 2, 2018.

An official representative of the municipality should initiate and authorize the creation of the municipality's access code and selection of the filing method. A building inspector contracted with the municipality may establish a login access code with this system only upon completion of an agreement between the inspector and the municipality, such as provided in the Act 211 Inspector-Muni Agreement. Maintain a copy of the agreement for your records. There is no need to submit the agreement to DSPS.


DSPS is offering three ways to electronically submit these permits:

  1. Applicants file permits electronically to the municipality through the DSPS system, and the municipality reviews the permits online through the same DSPS system. Permit information is automatically provided to DSPS.
  2. A municipality may use the CSV template file, provided by DSPS, to enter all permit information. The CSV file must be manually uploaded to the system each month and is then available in the electronic system.
  3. Municipalities that incorporate their own computerized permit filing system may interface with the Department's data connector software. See DSPS Building Permit System Application Programming Interface (API) for more information on implementing this option.

The Municipality Workspace provides the municipal representative access to permit information submitted by builders of for new one- and two- family dwellings. Municipality FAQ

Municipal building permits for new one- and two- family dwellings that differ from the one on the DSPS website may not be utilized until approved by the department.

Permit Pullers

Permit pullers must submit all required plans and data directly to the municipality per municipality’s instructions. The plans, data and permit must be reviewed, and the approved permit fee must be paid before the permit is considered an issued permit.

To file a building permit for a new one- and two- family dwelling, contact the municipality directly to determine how building permit applications should be filed.

To access the Electronic Building Permit System, please click here.

If you have questions on how to use the Electronic Building Permit System, please utilize the Requesting Electronic Building Permit FAQ.

Petition for Variance

A petition for variance from the Uniform Dwelling Code cannot be submitted through the eSLA system. Submit the completed SBD-9890X​ form with the ​appropriate fee to the address below. The Department will review the petition and issue a determination​ in accordance with Wis. Admin. Code SPS 320.19(3)​

Wisconsin Department of Safety and Professional Services
Division of Industry Services
4822 Madison Yards Way
PO Box 7302
Madison, WI 53707-7302

UDC Modular Manufacturer Application (PDF)
UDC Modular Manufacturer Application (fill-in)
UDC Modular Manufacturer Approval Procedures and Checklist
Wisconsin Uniform Building Permit Application (PDF)
Wisconsin Uniform Building Permit Application (fill-in)
(DoA Document Sales)
SBD-5824Wisconsin Uniform Building Permit Card (DoA Document Sales)
SBD-6025Inspection Report and Notice of Non-Compliance (DoA Document Sales)
SBD-6072One- and Two-Family Dwelling Permit to Start Construction
SBD-7611Solar Energy System Pre-Sale Information
UDC SealsUDC Seals and Program-Related Documents (DoA Document Sales)
Modular Home Program Insignia
Modular Home Program Insignia (DoA Document Sales)
SBD-9890XPetition for Variance Application
SBD-10837Erosion and Sediment Control Field Guide
SBD-10891Wisconsin Energy Efficiency Certificate
WorksheetOptional Makeup and Combustion Air Worksheet
Inspection ChecklistInspection Checklist for Typical One- or Two-Family Home
1000ISUDC Religious Waiver

Deck Codes SPS 321.225

Can we still use the UDC deck codes that we have always been using or is Appendix B the new code we have to enforce? How does Appendix C affect decks?

The department has determined that a deck can be built per the following methods effective January 1, 2016:

  • OPTION 1
    SPS 321.225 Decks. (1) Decks attached to dwellings and
    any detached decks that serve an exit shall comply with the applicable
    provisions of subchs. II to X of ch. SPS 321, including all
    of the following:
    (a) Excavation requirements under s. SPS 321.14;
    (b) Footing requirements under s. SPS 321.15 (2) (f);
    (c) Frost penetration requirements under s. SPS 321.16;
    (d) Load requirements under s. SPS 321.02;
    (e) Stair, handrail and guard requirements of s. SPS 321.04.
    (f) Decay protection requirements of s. SPS 321.10.
  • OPTION 2
    SPS 321.225 (2) A deck that complies with the standards in ch. SPS 320-325 Appendix B, and ch. SPS 320-325 Appendix C, if applicable, shall be considered as complying with sub. (1). Meaning, you would follow Appendix B and C exclusively.
  • OPTION 3
    Also, the department has determined that a deck designed and constructed to the DCA6 standard, (Prescriptive Residential Deck Construction Guide-2012 IRC version by The American Would Council), would be considered code compliant. The decision was based on several factors which included the following:
    -Based on prior analysis by the department, the DCA6 standard met or exceeded Wisconsin Uniform Dwelling Code requirements.
    -The DCA6 standard is primarily based on NDS standards, which the Department also adopts in SPS 320.24
    -Finally, utilizing the DCA6 standard would in fact be considered a form of structural analysis which is accepted under the scope of SPS321.02(2).

NOTE: You may not “mix and match” the options, meaning take parts from Appendix B then use parts of SPS 321.225(1).

Garage Penetrations SPS 321.08

I am inquiring about holes in an attached garage. Is there any code that requires the sealing of holes in the garage? We do seal all holes and boxes on the common wall but we have been cited twice for not sealing in the garage.

Yes, holes created in fire separations dwellings and garages must be protected. This includes holes that were drilled for wiring and not used.

SPS 321.08(1)(a) requires fire separation of dwelling units from attached garages.

SPS 321.08(3)(b) specifically addresses penetrations by electrical and plumbing components.

SPS 321.08(3)(b) (b) Electrical and plumbing components. Penetrations of a required separation by electrical and plumbing components shall be firmly packed with noncombustible material or shall be protected with a listed through-penetration firestop system with a rating of at least one hour.

Habitable Rooms in Basements SPS 321.05(2) & 323.02(3)(c)

I have a question regarding habitable rooms in basements without openable windows. In a rec room or theater room in the basement with no openable windows, SPS323.02 (3) (c) states a balanced mechanical ventilation system producing one air change per hour of fresh outside air while room is occupied must be provided. Does a simple exhaust fan in the basement rec room qualify for this ventilation?

No, you cannot simply exhaust air from the habitable room. There are two codes that require fresh outside air be brought in while in use for habitable rooms without openable windows. Fenestration air through leakage does not apply towards this. The codes are listed below:

SPS 321.05 Natural ventilation.
(2) VENTILATION. (a) 1. Balanced mechanical ventilation may be provided in lieu of openable exterior doors, skylights or windows provided the system is capable of providing at least one air change per hour of fresh outside air while the room is occupied.

SPS 323.02 (3) VENTILATION. (c) Habitable rooms.
Habitable rooms without openable windows shall be provided with a balanced mechanical ventilation system producing one air change per hour of fresh outside air while the room is occupied.

Is the required mechanical ventilation required to be tied into a light switch so it's on when the room is occupied?

The fan has to be tied to a switch that’s readily accessible however the code is silent as to whether it must be directly tied to a light switch. We do encourage you to consider the use of an occupancy sensor tied to the ventilation exhaust/makeup air system.

Ramp Footings SPS 321.16

I am looking for clarification on whether or not a ramp requires frost protection for landings that are built into the ramp. When you read SPS 321.16 (1) it states landings shall be placed below the frost penetration level or least 48” below adjacent grade. Do all landings require frost protection?

The code section below exempts the landings contained within the ramp. If the top of the ramp were to abut a landing or stoop with frost protected footing, then only that end of the ramp would need to comply. The rest of the ramp does not.

SPS 321.16 Frost protection. (1) EXCEPTIONS.
(d) Subsection (1) (a) does not apply to the footing for a ramp and its handrail posts unless the ramp abuts a frost-protected stoop or landing, in which case only the footing for that abutting end of the ramp is required to have the frost protection under sub. (1) (a), such as by bearing onto the stoop or landing, so that a tripping hazard is not created.

Note: See ch. SPS 325 Appendix A for further information.

SBD-10879Updated Solid Fuel-Fired Water Heating Appliances Brochure
Right to Cure Law"Right to Cure" Brochure
Wall Bracing UpdateWall Bracing Presentation
CBRF and Residential DHS Regulatory Model DHS Regulatory Model for 2015 Winter Code Updates
SBD-10715Information on State Building Plan Review Requirements Before Municipalities Issue Permits, Can be Posted by Municipalities
Rules for Water HeatersRules for Water Heaters Used as Space Heaters
Building A Home in WisconsinInformational Brochure on Uniform Dwelling Code in Wisconsin
Smoke Detectors Save LivesOne- and Two-Family Dwellings Need Smoke Alarms and Carbon Monoxide Alarms Brochure
Camping Unit Contracts ContactsCamping Unit Permit and Inspections Contacts
Soil Erosion Guidance Publication UWEXStandard Erosion Control Plan for 1- & 2-Family Dwelling Construction Sites
Erosion Control for Home Builders
Inspection Checklist POST 2007Manufactured Home Installation Inspection Checklist POST 4/1/2007
Inspection Checklist PRE 2007Manufactured Home Installation Inspection Checklist PRE 4/1/2007
Soil Erosion Control Plan Audit?
2017 Soil Erosion Audit Changes
Deck Column Footing Size WorksheetWorksheet for determining footing size
Heat Loss Calculator with InstructionsHeat Loss Calculator and Instructions (.xslx)

REScheck is a software application that has been created by the Federal Department of Energy for demonstrating compliance with building envelope requirements of various State building codes.

Effective January 1, 2016, the Wisconsin Uniform Dwelling Code updated its energy conservation code to the 2009 International Energy Conservation Code. As before, compliance with the UDC can be shown by use of the federal REScheck program. However the newest software version available on the federal DOE website no longer has the option to calculate heating plant sizing. In order to continue to offer that service, here is a link to the older version of REScheck, build version (This may be confirmed by looking at “About” under “Help” on the menu bar of the software. Note that you may have problems if you have more than one version of REScheck on your computer). If you use this version, you must first calculate building envelope compliance by selecting the “2009 IECC” under “Code” on the menu bar, even though you may see a warning that your location requires use of the “Wisconsin 2009” code. After printing that out and without exiting REScheck, you may switch your code to “Wisconsin 2009”, enter your county location and calculate your heating plant size on the Loads tab, as before.

Alternatively to size your heating plant by hand calculation after you have calculated building envelope compliance per the 2009 IECC, you would perform the following calculations, ignoring the units of measure:

  1. Multiply the value in the “Your UA” field, from the Envelope tab of Rescheck, by the temperature difference for your dwelling location, which is 70 minus the value from the Outdoor Design Temperature of SPS 323.02(1) table and map in Appendix A of the UDC (link). (Note that subtracting a minus value is the same as adding.)
  2. Calculate your conditioned building volume by multiplying your total conditioned floor area including basements in square feet by its average ceiling height in feet.
  3. Select an air infiltration rate between 0.2 and 0.5 air changes per hour, based on your estimated dwelling envelope tightness.
  4. Multiply the building volume value from step 2 by your selected air infiltration rate from step 3 and by your temperature difference and by the constant 0.018.

Add together the values from steps 1 and 4 to obtain your minimum heating plant output capacity, in BTU/hour. (Note that the UDC no longer has an over-sizing limit.)

Wisconsin product approvals are typically valid for five years unless there is a relevant code change. During the approval period, the product approval may be included with individual project submittals and used for the term of the project approval, which may extend past the product approval term. Product approvals are listed on this website for the term of their approval. Contact DIS if a copy of an expired approval is needed.

Click Here for Manufacturers of Approved Building Materials

Submit product approval applications via eSLA