Commercial Plumbing Contractor in St. Louis, MO & Surrounding Areas
Legacy Plumbing is a self-performing commercial plumbing contractor for general contractors, developers, and facility owners across the St. Louis metro and a 2-hour radius. Ground-up new construction, underground site utilities, design/build, and complex commercial systems.
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Commercial Plumbing Services Across St. Louis
A complete commercial scope — from the first underground sleeve to the final inspection.
Design/Build & Preconstruction
Early budgeting, constructability review, and value engineering with your design team to de-risk the schedule.
Learn moreGround-Up New Construction
Underground rough-in, top-out, trim-out, and final inspections sequenced with your GC schedule.
Learn moreUnderground & Site Utilities
Self-performed sanitary, storm, water service, and grease waste with in-house excavation equipment.
Learn moreTenant Improvements & Build-Outs
Restaurant, retail, office, medical, and dental TI work — coordinated to keep your opening date.
Learn moreMedical & Process Gas Piping
Brazed med gas, lab gas, and process piping installed, certified, and tested to NFPA 99.
Learn moreBackflow Install & Annual Testing
RPZ and DCVA assemblies installed, repaired, and certified to meet local code.
Learn moreHydro-Jetting & Sewer Repair
Camera inspection, jetting, and trenchless repair for commercial sewer and drain lines.
Learn moreCommercial Service & Maintenance
Planned maintenance and scheduled service from 7am–3:30pm daily from our dedicated service division.
Learn more
Underground & Site Utilities — In-House Across St. Louis
We own and operate our own excavators, skid steers, and mini-excavators so we can self-perform underground sanitary, storm, water service, and grease waste. One trade, one schedule, one point of accountability.
- Underground sanitary & vent
- Storm & roof drain
- Domestic water service
- Grease waste & interceptors
- Site utility tie-ins
- Backflow & meter pits
Commercial Plumbing Across Every Sector
Commercial Service & Maintenance — St. Louis Metro
When a backed-up line or failed water heater threatens revenue, our service division dispatches a stocked truck as scheduled. We support the buildings we build — and the ones we didn't.
- Scheduled service from 7am–3:30pm daily
- Planned preventative maintenance
- Backflow testing & certification
- Water heater & boiler service
- Drain cleaning & hydro-jetting
- Repipe & leak repair
Bidding a Project in St. Louis?
Get a bid from a self-performing commercial plumbing contractor headquartered in O'Fallon, MO, serving the greater St. Louis region.