Plumbing Permit in St. Louis, Missouri
It depends
Sometimes, depending on the project
Before any plumbing, drainlaying or process drainage work, any connection to a sewer, and any installation, replacement or permanent removal of a backflow prevention device.
By Mario Bailey, verified against official sources
Quick answer
The City Plumbing Code requires a permit before plumbing, drainlaying or process drainage work, before any connection to a sewer, and before installing, replacing or permanently removing a backflow prevention device, with minor repairs carved out. Minor repairs mean repairs to traps or cocks, opening waste or supply pipes, traps or drains, or frozen pipes; they stop being minor as soon as connections to soil, supply, waste or vent pipes are disturbed or a fixture is set or replaced. Clearing a stoppage or fixing a leak is exempt as long as no valve, pipe or fixture is replaced or rearranged; if a concealed trap or pipe has to come out and be replaced with new material, the code treats that as new work needing a permit. Permits go to plumbing contractors licensed by the City of St. Louis, and there is no statewide plumbing license standing in for that.
Who is pulling this permit?
Apply yourself
Hire it out
Before you sign, ask the contractor:
- Who pulls the permit, you or me, and is the permit fee included in the bid?
- Which inspections will this job need, and who meets the inspector on site?
- Is your contractor license active in this locality, and under which business name?
When a permit is usually needed
Before any plumbing, drainlaying or process drainage work, any connection to a sewer, and any installation, replacement or permanent removal of a backflow prevention device.
What a plumbing permit costs in St. Louis
How to apply in St. Louis
You apply for a residential plumbing permit at your local building department by filing an application that describes the scope of work and site, along with construction documents, before any regulated plumbing installation, alteration, or repair begins. Minor repairs that do not touch piping or fixtures are generally exempt, and once issued the permit only stays valid if work is started within its time limit.
What most plumbing permit applications include:
- A permit is required before any owner or authorized agent constructs, alters, repairs, removes, converts, or replaces a plumbing system regulated by the code (IRC R105.1).
- The application must identify and describe the work, describe the site, state the intended use and occupancy, and be signed by the applicant or an authorized agent (IRC R105.3).
- Two or more sets of construction documents must accompany the application, drawn with enough clarity to show the location, nature, and extent of the proposed plumbing work and how it will conform to code (IRC R106.1, R106.1.1).
- Minor plumbing repairs, such as clearing a stoppage or removing and resetting a water closet without rearranging pipes or fixtures, are exempt from permit (IRC R105.2).
- Once issued, a permit is only valid for a limited window, commonly 180 days, and becomes invalid if the work is not started or is abandoned within that time, though extensions can be requested (IRC R105.3.2, R105.5).
General submittal guidance from 2021 International Residential Code (IRC), Chapter 1 Scope and Administration, Sections R105 Permits and R106 Construction Documents. Source. City of St. Louis Building Division, Permit Section (Department of Public Safety) sets the exact checklist for St. Louis.
Where to apply in St. Louis:
City of St. Louis Building Division, Permit Section (Department of Public Safety)
- Building Division Permit Section, City Hall, 1200 Market Street, Room 425, St. Louis, MO 63103
- Phone: (314) 622-3313
- Email: stlcitypermits@stlouis-mo.gov
Inspections and closing out your permit
Plumbing inspections are timed to whatever is about to hide the pipe: underground and under-slab piping is checked before concrete covers it, rough-in piping is pressure or water tested before walls close up, and a final inspection checks every fixture and backflow protection once the work is complete.
- Piping and equipment placed under a slab or floor must be in place and inspected before any concrete is poured or floor sheathing is installed over it (IRC R109.1.1.1).
- Rough plumbing, along with the mechanical, gas, and electrical rough-in, must be inspected prior to covering or concealment and before fixtures or appliances are set (IRC R109.1.2).
- Rough drain, waste, and vent (DWV) piping is tested with water, air, or (for plastic piping) a vacuum, and must show no evidence of leakage before it is closed in (IRC P2503.5.1).
- The water-distribution piping is tested and must hold tight under the system's working pressure, or under a 50 psi air test for non-plastic piping, before it is concealed (IRC P2503.7).
- The framing inspection cannot proceed until the plumbing rough inspection, along with the mechanical and electrical rough inspections, has been approved (IRC R109.1.4).
- At the final drainage test, each fixture is filled and then drained, and its traps and fixture connections must prove watertight by visual inspection (IRC P2503.5.2).
- Final inspection is made after all work required by the permit is complete, and includes confirming backflow protection, such as vacuum breakers on hose bibbs, is installed (IRC R109.1.6, P2902.4.3).
Schedule each inspection in advance and pass the final before you use the work or close the permit. Request inspections through the St. Louis permit portal or by phone at (314) 622-3313.
Inspection sequence from 2021 International Residential Code (IRC), Section R109 Inspections and Section P2503 Inspection and Tests. Source. An open permit left un-inspected can surface later in a title search or home sale.
Your Plumbing Permit checklist for St. Louis
- Confirm the requirement. Sometimes, depending on the project. Usually needed: Before any plumbing, drainlaying or process drainage work, any connection to a sewer, and any installation, replacement or permanent removal of a backflow prevention device.
- Budget the fee. Plumbing permit fees are established by City Ordinance 71644. The application fee for all plumbing permits is $30.00. Fixtures (floor drain, sump, water heater, reduced pressure backflow device or double gate/double check valve, roof drain or trapped outlet) are $10.00 each; a tap, water connection or extension is $25.00 each; a sewer extension, connection or repair is $25.00 each; irrigation system zones are $25.00 each; rough inspection $25.00; finish inspection $25.00; re-inspection $30.00. Starting work before the permit issues triggers a surcharge that scales with the permit fee, from $35.00 on a $0 to $50.00 permit up to $1,005.00 over $10,000.00. Official fee schedule.
- Apply. You apply for a residential plumbing permit at your local building department by filing an application that describes the scope of work and site, along with construction documents, before any regulated plumbing installation, alteration, or repair begins. Minor repairs that do not touch piping or fixtures are generally exempt, and once issued the permit only stays valid if work is started within its time limit. Start at the St. Louis permit portal.
- Keep the office details handy. City of St. Louis Building Division, Permit Section (Department of Public Safety). Phone: (314) 622-3313. Address: Building Division Permit Section, City Hall, 1200 Market Street, Room 425, St. Louis, MO 63103.
- Plan for inspections. Plumbing inspections are timed to whatever is about to hide the pipe: underground and under-slab piping is checked before concrete covers it, rough-in piping is pressure or water tested before walls close up, and a final inspection checks every fixture and backflow protection once the work is complete.
Compiled from the official sources on this page. Last checked .
Frequently asked questions
- Do you need a plumbing permit in St. Louis?
- The City Plumbing Code requires a permit before plumbing, drainlaying or process drainage work, before any connection to a sewer, and before installing, replacing or permanently removing a backflow prevention device, with minor repairs carved out. Minor repairs mean repairs to traps or cocks, opening waste or supply pipes, traps or drains, or frozen pipes; they stop being minor as soon as connections to soil, supply, waste or vent pipes are disturbed or a fixture is set or replaced. Clearing a stoppage or fixing a leak is exempt as long as no valve, pipe or fixture is replaced or rearranged; if a concealed trap or pipe has to come out and be replaced with new material, the code treats that as new work needing a permit. Permits go to plumbing contractors licensed by the City of St. Louis, and there is no statewide plumbing license standing in for that. Always confirm with the City of St. Louis Building Division, Permit Section (Department of Public Safety) before starting.
- How much does a plumbing permit cost in St. Louis?
- Plumbing permit fees are established by City Ordinance 71644. The application fee for all plumbing permits is $30.00. Fixtures (floor drain, sump, water heater, reduced pressure backflow device or double gate/double check valve, roof drain or trapped outlet) are $10.00 each; a tap, water connection or extension is $25.00 each; a sewer extension, connection or repair is $25.00 each; irrigation system zones are $25.00 each; rough inspection $25.00; finish inspection $25.00; re-inspection $30.00. Starting work before the permit issues triggers a surcharge that scales with the permit fee, from $35.00 on a $0 to $50.00 permit up to $1,005.00 over $10,000.00. See the official fee schedule for current amounts.
- How long does a plumbing permit take in St. Louis?
- Approved permit or feedback by email within 10 business days of submission, and most applications are approved within 1 to 3 business days. Times can vary by workload and project scope, so confirm with the office.
- Where do you apply for a plumbing permit in St. Louis?
- You can apply through the St. Louis permit portal or contact the City of St. Louis Building Division, Permit Section (Department of Public Safety) directly. The links are listed on this page.
- Can a homeowner pull a plumbing permit themselves in St. Louis?
- Under Missouri law (RSMo 701.055.1 and 701.055.2; RSMo 327.101.2(5)(a); RSMo 327.191.2(5)(a); RSMo 700.656.5): Missouri does not license general contractors at the state level and has no statewide owner-builder permit statute, disclosure affidavit, or resale restriction comparable to Florida's one year rule. Whether a homeowner may pull the permit and do the work is decided by the city or county that issues the permit. Where state law does speak, it is permissive: RSMo 327.101.2(5)(a) and RSMo 327.191.2(5)(a) let an unlicensed person render architectural and engineering services for the construction, remodeling or repair of a privately owned dwelling house, provided the drawings say the person is not licensed, so plans for a house do not have to be sealed by an architect or engineer. RSMo 701.055.1 expressly preserves a property owner's right to install, modify or repair their own on-site sewage disposal system as long as the state standard is met, and RSMo 701.055.2 adds that no permit or contractor registration is required simply to clean it. RSMo 700.656.5 exempts a person who installs a manufactured home on his or her own property for his or her own occupancy from the otherwise mandatory state installer license. None of these exemptions excuses a local permit where the local jurisdiction requires one. Confirm how St. Louis applies this before you apply.
From the Library
What else needs a permit in St. Louis
Every other permit type we have verified for this jurisdiction, with the rule that applies here.
| Project | Permit needed? | Threshold | Typical fee |
|---|---|---|---|
| Deck Permit | It depends | inches above adjacent grade for an uncovered wood deck or patio resting directly on the ground or a rock base with no permanent foundation | Charged as a building permit on estimated construction cost: $25.00 application fee plus... |
| Electrical Permit | It depends | Not specified | Electrical permit fees are established by City Ordinance 70802. |
| Fence Permit | It depends | Not specified | A fence is permitted as a Miscellaneous Structures Permit under Section 109.2.3 of the... |
| HVAC Permit | It depends | Not specified | Mechanical permit fees are established by City Ordinance 70800. |
| Patio Permit | It depends | Not specified | A patio cover is charged as a building permit on estimated construction cost: $25.00... |
| Pool Permit | It depends | inches of water depth, applied together with a 250 square foot surface area test | Charged as a building permit on estimated construction cost: $25.00 application fee plus... |
| Roof Replacement Permit | It depends | percent of roof sheathing removed and replaced during a like-material roof covering replacement | Charged as a building permit for alterations and repairs on estimated construction cost:... |
| Shed Permit | It depends | square feet of floor area for a detached accessory building, which must also keep the setbacks required by the Zoning Ordinance | Charged as a building permit on estimated construction cost: $25.00 application fee plus... |
| Solar Permit | Permit required | Not specified | Charged as a building permit on estimated construction cost: $25.00 application fee plus... |
Plumbing Permit in other Missouri localities
Everything above, sourced
Code references
National and state model-code sections the general guidance on this page is drawn from. They are not St. Louis documents; the office above sets the local rules.
Verified by a person against the sources above on , not confirmed with City of St. Louis Building Division, Permit Section (Department of Public Safety). Rules change; confirm before you build. How we verify.
Last checked: Report an error on this page
Compare Plumbing Permit requirements across Missouri localities
Permit office
City of St. Louis Building Division, Permit Section (Department of Public Safety)
(314) 622-3313Permit portal