# What do Chicago's plumbing code changes mean for a repipe? > Chicago plumbing code changes for repipes: the Phase 3 ordinance passed June 17, 2026, the 2021 amendments and the 80 psi valve rule. See what changes for you. URL: https://chicagolakerepiping.com/blog/chicago-plumbing-code-modernization-repipes/ The City Council's Phase 3 codes ordinance and the 2021 interim amendments both touched the plumbing code. Here is what each changed for replacing water supply pipe, and what stayed the same. Last Updated: October 25, 2026 **Chicago’s recent plumbing code changes adjust how a repipe is designed, not what it is made of.** The Phase 3 construction codes ordinance, passed by the City Council on June 17, 2026, lowers the pressure at which a pressure-reducing valve is required to 80 psi, among other changes. The 2021 interim amendments widened how copper can be joined. Neither one added PEX for drinking water, so a repipe inside the city is still copper. [Chicago Lake Repiping](https://chicagolakerepiping.com/) offers and manages [whole-house repiping](https://chicagolakerepiping.com/whole-house-repiping/) and [copper repiping](https://chicagolakerepiping.com/copper-repiping/) across Chicago and nearby Cook County suburbs, with the work done by licensed and insured plumbing contractors. This post summarizes the two rounds of changes as they bear on replacing water supply pipe. ## The Phase 3 ordinance The Phase 3 Construction Codes Modernization ordinance, Substitute Ordinance SO2026-0024930, was introduced on April 15, 2026 and received final action on June 17, 2026. The Department of Buildings announced that its new provisions could be used from October 1, 2026 and are mandatory for permit applications started on or after December 1, 2026. Several of its plumbing changes reach into a repipe. **Pressure-reducing valves.** Section 18-29-604.8 now requires a pressure-reducing valve where static pressure exceeds 80 psi at any fixture or outlet, reducing it to 80 psi or less. The earlier threshold was 100 psi. A building that would not have needed a valve before can need one now. The [Chicago water pressure guide](https://chicagolakerepiping.com/guide/chicago-water-pressure-prv/) explains what the valve does and how pressure is measured. **Hot and cold interconnections.** Section 18-29-604.2 now requires check valves or other provisions at points where the hot and cold water systems interconnect, so water cannot cross from one side to the other there. **Water heater relief valves.** The temperature and pressure relief setting in section 18-29-504.6 changed to not more than 210°F. That matters when a repipe also replaces the water heater. **Hot water pipe rating.** The rating for hot water distribution pipe in section 18-29-605.5 was corrected to 100 psi at 180°F. **Service and riser sizes.** The code’s sizing appendix keeps the rule that no water service may be smaller than 1 inch nominal pipe size, with 1.5 inches for the service and 1.25 inches for the riser where 1-inch flushometer valves are used. It deletes the line that set a 3/4-inch minimum for risers. Riser size is part of the design, so ask how the risers on a quote were sized, especially in a [two-flat](https://chicagolakerepiping.com/two-flat-repiping/) or a building with [shared risers](https://chicagolakerepiping.com/riser-replacement/). ## The 2021 interim amendments The earlier round came in Ordinance O2021-4134, adopted October 14, 2021, effective October 19, 2021 and mandatory for permit applications from March 1, 2022. The Department of Buildings described it as following a four-year study of alternative materials with about 3,000 participants. **PVC for drains.** The amendments expanded the use of PVC for drain, waste and vent pipe in low- and mid-rise residential buildings. That is the drain system, not the water supply; see [does repiping include drains](https://chicagolakerepiping.com/guide/does-repiping-include-drains/). **Joining copper.** Copper water tube can now be joined by soldering with lead-free solder and flux, brazing, mechanical and threaded joints, welding, press-connect fittings pressed with a tool certified by the fitting manufacturer, and listed push-fit fittings. Press fittings make a joint without an open flame, which can matter inside an old wall with dry framing behind the plaster. **Lead content.** Pipe, fittings, valves and faucets that supply drinking water must comply with NSF 372, with a weighted average lead content of 0.25% or less. **Connectors.** Flexible water connectors must stay accessible, and connectors to faucets and toilets are limited to 30 inches. ## What did not change **The material.** The code’s table of water distribution pipe, Table 18-29-605.5, lists brass, copper and copper-alloy pipe and tube, and galvanized steel. CPVC, polypropylene and PVDF appear only for secondary water in process applications. PEX is not listed, and neither round of changes added it. Homeowners report holding off on replacing galvanized in the hope that the City will allow PEX; nothing in either ordinance points that way. The [guide to whether PEX is allowed in Chicago](https://chicagolakerepiping.com/guide/is-pex-allowed-in-chicago/) covers the history. **Freeze protection and burial depth.** The rules that new concealed water pipe and pipe exposed to low temperatures be protected from freezing, and that water service pipe in the ground have at least 5 feet of cover, were not amended by either ordinance. **Permits and licensing.** Replacing existing piping still goes through a Department of Buildings permit, and the work is done by a Chicago-licensed plumbing contractor or by the owner of a detached single-family home doing their own work. The [permit guide](https://chicagolakerepiping.com/guide/chicago-repiping-permit/) covers the Express application and fees. ## The suburbs follow their own codes These are City of Chicago changes. Suburbs enforce their own adopted plumbing codes: Oak Park and Skokie follow the Illinois Plumbing Code, which lists PEX for water distribution, while Evanston’s and Park Ridge’s codes call for copper. The rules for a suburban address, including any pressure valve threshold, are confirmed per address before work starts. See [PEX repiping in the suburbs](https://chicagolakerepiping.com/pex-repiping/). ## What to do with this If a repipe is coming, the practical effects are three: expect the static pressure reading to decide whether a valve goes in, ask how the risers are sized, and if the water heater is being replaced, expect its relief valve to meet the new setting. For the bigger picture of why and when to repipe, the [galvanized pipes guide](https://chicagolakerepiping.com/guide/galvanized-pipes-chicago-homes/) is the place to start, and a call to the number on this page sets up a walk-through. ## Questions about this post ### Did Chicago's new plumbing code allow PEX? No. Neither the 2021 interim amendments nor the Phase 3 ordinance added PEX or another plastic pipe for drinking water distribution. The 2021 amendments expanded PVC for drain, waste and vent pipe in low- and mid-rise homes, which is a separate system. A repipe inside the city is still copper. ### When do Chicago's new plumbing rules apply to a repipe? The Department of Buildings made the Phase 3 provisions optional from October 1, 2026 and mandatory for permit applications started on or after December 1, 2026. A permit follows the code edition in effect when its application was submitted, so the date the repipe permit is applied for decides which rules it is designed to. ### What is the biggest Phase 3 change for a house being repiped? The pressure-reducing valve threshold. A valve is now required where static pressure at any fixture or outlet exceeds 80 psi, down from 100 psi, and it must bring the pressure to 80 psi or less. That makes the static pressure reading at the first visit part of the code check. ## Keep reading - Learn [When does Chicago's plumbing code require a pressure-reducing valve?](https://chicagolakerepiping.com/guide/chicago-water-pressure-prv/)The City's updated threshold for a pressure-reducing valve, what the valve does at the meter, why high static pressure stresses old and new piping, and how it fits into a repipe. - Learn [Do you need a permit to repipe a house in Chicago?](https://chicagolakerepiping.com/guide/chicago-repiping-permit/)What the Department of Buildings' Express permit covers when repiping a Chicago building, what pushes a job into plan review, the documents a riser or condo job needs, and what the suburbs do differently. - Decision Guide [Is PEX allowed in Chicago?](https://chicagolakerepiping.com/guide/is-pex-allowed-in-chicago/)Where PEX is and is not allowed: what Chicago's water distribution table actually lists, what the 2021 and Phase 3 code changes did and did not touch, which suburbs allow PEX, and what to do about plastic pipe already in the house. - Learn [Galvanized pipes in Chicago homes: what to do about them](https://chicagolakerepiping.com/guide/galvanized-pipes-chicago-homes/)How to tell whether a Chicago bungalow, two-flat or greystone home still has galvanized steel supply pipe, what its symptoms do and do not prove, and how Chicago's code, permits and lead rules shape the fix.