For those of you who are submitting to any delegated municipality or to the State of Wisconsin for the first time for plumbing plan review from outside the State – Welcome!

The goal of this is to help highlight and prepare you for some key differences so you know what to prepare for and expect as you submit your project for plan review. It is also to help you quickly locate critical issues in the Wisconsin Plumbing Code. Oftentimes when we receive plans for new restaurants or other projects and the designer is familiar with the ICC suite of codes and standards – Wisconsin’s own homegrown plumbing code can catch even the most experienced engineers, architects, and contractors off guard if they aren’t used to it.

Wisconsin is one of only two states in the nation with their own Plumbing Code – Illinois is the other. Our state plumbing codes, plumbing product approval, and licensing is the responsibility of the State of Wisconsin Department of Safety and Professional Services (aka DSPS). The codes that directly relate to plumbing design and construction are part of the DSPS code system and are:

Chapters SPS 381 – 387 and can be found here. They are highlighted as follows:

SPS381 – Definitions and Standards

SPS382 – Design, Construction, Installation, Supervision, Maintenance And Inspections Of Plumbing. This is the main body of the plumbing design and installations codes for the state of Wisconsin. See below for further breakdown of this chapter.

SPS383 – Private Onsite Wastewater Treatment

SPS384 – Plumbing Products  All products, piping and fixtures must meet the criteria/standards in this chapter to be installed in the state of Wisconsin

SPS385 – Soil and Site Evaluations

SPS386 – Boat and Onshore Sewage Facilities

SPS387 – Private Onsite Wastewater Treatment System Replacements or Rehabilitation

For the purposes of this blog spotlight to help our submitters – we are just going to focus the rest of our conversation on SPS 382. This is the heart of the plumbing code in Wisconsin and it will better prepare you for what to expect when you submit.

While many parts of the DSPS plumbing codes are similar to International Codes, some areas of this code are much different including sizing calculations unique to Wisconsin.

Below is a breakdown and a brief description of each of the SPS382 subchapters and where to look as you dive into the Wisconsin Plumbing Code:

The 5 most common differences as seen on submitted plans between the Wisconsin Plumbing Code and the International Code Suite:

  1. RESTURANT SINKS: Three and four compartment restaurant scullery sinks require a direct connection to the greasy or sanitary drain system, not indirect drainage to a floor sink as per the International Codes.
  1. BACKFLOW / CROSS CONNECTION: Cross connection control and backflow prevention is required at the water supply to every piece of equipment, fixture, plumbing appliance and piping system, not only at the building water supply entrance as required by some of the International Codes.
  1. SANITARY AND STORM SIZING AND DESIGN: Sanitary and storm sewer and drainage systems along with water supply distribution systems have varying degrees of design/sizing differences vs the International Code Suite. Please double check your pipe sizing before submitting.
  1. VENTING SYSTEM ALTERNATES: Depending on your design, there are various sanitary venting systems are available in lieu of individual fixture venting. Example of these alternatives are Circuit Venting, Combination, Drain/Vent System, Common Venting, Wet Venting, and depending on the location Air Admittance Valves can be an option.
  1. HOT WATER RECIRCULATING: The State of Wisconsin is now requiring conformance to the IECC Table C404.5.1 in regard to hot water recirculating piping requirements to all public hand washing sinks and public lavatories. These requirements are more stringent than the hot water recirculating requirements in SPS382.40

E-Plan Exam looks forward to partnering with you to provide a safe, sanitary, and properly designed plumbing system for the project you are submitting!

Take care and see you on the next project!