# New Construction > Commercial New Construction Plumbing; St. Louis, St. Charles and Jefferson County; Underground Rough-In. Canonical: https://legacyplumbingmo.com/services/new-construction Last updated: 2026-10-28 Ground-Up Commercial Legacy Plumbing has installed commercial plumbing systems for new-build projects across the St. Louis metro since 1996. Our master-licensed team handles everything from underground rough-in through final fixture trim-out, on schedule and on budget. Contact Us [636-978-0120](tel:+16369780120) ## Bid My New Construction Project Tell us about your project — we respond within one business day. Who We Serve ## Who We Serve on Ground-Up Work - Industrial and manufacturing facilities - Warehouse, distribution and cold storage - Medical office buildings and clinics - Schools and municipal buildings - Mid-size commercial shells and retail centers - General contractors bidding plan-and-spec work ### Explore More - [Design-Assist & Preconstruction](https://legacyplumbingmo.com/services/design-assist-preconstruction) - [Tenant Build-Out](https://legacyplumbingmo.com/commercial/tenant-finish) - [Plumbing in O'Fallon, MO](https://legacyplumbingmo.com/locations/ofallon) - [All Commercial Services](https://legacyplumbingmo.com/commercial) For ground-up projects that also need site work and underground utilities, Kuesel, our sister company under Kuesel Holding Company, handles the earthwork and [water and sewer site utilities](https://kueselinc.com/services/water-sewer) . Our Process ## How a New Construction Job Runs ### Takeoff & Hard Bid We price off your plans and specs, flag scope gaps, and return a written number your estimator can rely on. ### Underground Rough-In Sanitary, storm and water service set and tested before the slab pour, coordinated with the site contractor. ### Above-Ground Rough Waste, vent, domestic water and gas run tight to the model so other trades keep moving. ### Trim & Fixture Set Fixtures, carriers, water heaters and specialties installed and protected for turnover. ### Test, Inspect, Close Out Pressure tests, chlorination, inspector walk and O&M documents delivered with the punch list clear. ## Why Choose Legacy for New Construction Why Contractors Hand Us the Plumbing Scope ### A commercial contractor since 1996 We are primarily a commercial contractor, with select residential service through our service division. Every crew we field has built commercial and industrial systems. ### Master-licensed across the metro Licensed in St. Louis City, St. Louis County, St. Charles County and Jefferson County jurisdictions. ### Manpower that holds the schedule UA Local 562 manpower means we can add bodies when the GC compresses the schedule instead of asking for more float. ### Written pre-job planning Every job starts with a written plan so material, manpower and inspections are sequenced before day one. Need site utilities, excavation or earthwork? Work with our sister company [Kuesel](https://kueselinc.com/) , under Kuesel Holding Company. ## Request a New Construction Bid Send scope, schedule and site address. We reply within one business day. ## Bid My New Construction Project Tell us about your project — we respond within one business day. For examples of this work, see [Ground-Up Site Utilities (O'Fallon, MO)](https://legacyplumbingmo.com/projects/ground-up-site-utilities-ofallon-mo) , [Cold Storage Facility in Foristell (Foristell, MO)](https://legacyplumbingmo.com/projects/cold-storage-facility-foristell-mo) and [Middle School Renovation in St. Charles (St. Charles, MO)](https://legacyplumbingmo.com/projects/middle-school-renovation-st-charles-mo) . For planning guidance, read [Underground Plumbing Before the Slab: A Commercial Coordination and Inspection Checklist](https://legacyplumbingmo.com/resources/underground-plumbing-before-the-slab-checklist) and [How Prefabricated Plumbing Assemblies Shorten Schedules on Multifamily, Hotel, Healthcare and School Projects](https://legacyplumbingmo.com/resources/prefabricated-plumbing-assemblies-shorten-schedules) . ### Related Services - [New Construction Plumbing in O'Fallon, MO](https://legacyplumbingmo.com/commercial/new-construction-plumbing-ofallon-mo) - [Design-Assist & Preconstruction](https://legacyplumbingmo.com/services/design-assist-preconstruction) - [Tenant Build-Out](https://legacyplumbingmo.com/commercial/tenant-finish) ### Next Steps - [Request Service](https://legacyplumbingmo.com/request-service) - [View All Commercial Services](https://legacyplumbingmo.com/commercial) - [Request a Free Estimate](https://legacyplumbingmo.com/contact-us) ## Where we work ### St. Charles County - [Commercial plumbing in St. Charles County](https://legacyplumbingmo.com/locations/st-charles-county) - [Commercial plumbing in O'Fallon](https://legacyplumbingmo.com/locations/ofallon) - [Commercial plumbing in St. Peters](https://legacyplumbingmo.com/locations/st-peters) - [Commercial plumbing in St. Charles](https://legacyplumbingmo.com/locations/st-charles) - [Commercial plumbing in Wentzville](https://legacyplumbingmo.com/locations/wentzville) - [Commercial plumbing in Lake Saint Louis](https://legacyplumbingmo.com/service-area/lake-st-louis-mo) - [Commercial plumbing in Dardenne Prairie](https://legacyplumbingmo.com/service-area/dardenne-prairie-mo) - [Commercial plumbing in Cottleville](https://legacyplumbingmo.com/service-area/cottleville-mo) ### Lincoln County - [Commercial plumbing in Troy](https://legacyplumbingmo.com/service-area/troy-mo) - [Commercial plumbing in Moscow Mills](https://legacyplumbingmo.com/service-area/moscow-mills-mo) - [Commercial plumbing in Elsberry](https://legacyplumbingmo.com/service-area/elsberry-mo) ### Warren County - [Commercial plumbing in Warrenton](https://legacyplumbingmo.com/service-area/warrenton-mo) - [Commercial plumbing in Wright City](https://legacyplumbingmo.com/service-area/wright-city-mo) - [Commercial plumbing in Marthasville](https://legacyplumbingmo.com/service-area/marthasville-mo) ### St. Louis County - [Commercial plumbing in Chesterfield](https://legacyplumbingmo.com/locations/chesterfield) - [Commercial plumbing in Clayton](https://legacyplumbingmo.com/locations/clayton) - [Commercial plumbing in Affton](https://legacyplumbingmo.com/service-area/affton-mo) - [Commercial plumbing in Ladue](https://legacyplumbingmo.com/service-area/ladue-mo) - [Commercial plumbing in Brentwood](https://legacyplumbingmo.com/service-area/brentwood-mo) ### Jefferson County - [Commercial plumbing in Jefferson County](https://legacyplumbingmo.com/locations/jefferson-county) - [Commercial plumbing in Arnold](https://legacyplumbingmo.com/service-area/arnold-mo) - [Commercial plumbing in Festus](https://legacyplumbingmo.com/service-area/festus-mo) - [Commercial plumbing in Crystal City](https://legacyplumbingmo.com/service-area/crystal-city-mo) ### St. Louis City - [Commercial plumbing in St. Louis](https://legacyplumbingmo.com/locations/st-louis) - [Commercial plumbing in Central West End](https://legacyplumbingmo.com/service-area/central-west-end-mo) - [Commercial plumbing in Compton Heights](https://legacyplumbingmo.com/service-area/compton-heights-mo) - [Commercial plumbing in Lafayette Square](https://legacyplumbingmo.com/service-area/lafayette-square-mo) [All commercial plumbing service areas by county](https://legacyplumbingmo.com/service-areas) ## Need a Plumber in St. Louis or the Surrounding Area? Written bids within one business day, scheduled service Monday–Friday 7am–4pm (emergency calls answered 24/7 — nights & weekends billed at premium rates), and union-trained crews since 1996 across the St. Louis metro and a 2-hour radius. [Get Free Estimate](https://legacyplumbingmo.com/contact-us) [636-978-0120](tel:+16369780120) ## From Our Job Sites Restroom group rough-in in framed walls Restroom fixture rough-in with carriers Copper water and PVC drain lines run overhead Overhead PVC drain and vent piping in a commercial building Underground rough-in bedded in gravel Overhead PVC piping above an insulated ceiling ## Related - [Contact Legacy Plumbing](https://legacyplumbingmo.com/contact-us) - [Company facts](https://legacyplumbingmo.com/company-facts) - [All pages (llms.txt)](https://legacyplumbingmo.com/llms.txt)