What commercial plumbing covers
Commercial plumbing is a different trade from residential service, even when the same license covers both. It deals with larger supply lines, grease traps and interceptors for restaurants, backflow prevention devices required by code, multi-fixture restrooms, boiler and water heater systems sized for occupancy, and drainage that has to handle far more volume than a house. Work orders range from routine maintenance contracts for office parks and retail strips in Irmo to full rough-in plumbing for new construction or tenant buildup. There are 8 businesses in this category, and their range of experience varies from small crews that handle service calls to outfits equipped for ground-up commercial jobs.
What to look for before you hire
Check that the contractor carries commercial general liability coverage at limits that match your lease or insurance requirements, and ask whether they're familiar with backflow testing and certification, since most municipalities require annual documentation. Ask about response time for emergencies (a burst line or backed-up sewer in a business shuts down revenue fast), and whether they staff enough licensed plumbers to handle a multi-fixture job without dragging it out. Get a written scope and timeline for anything beyond a simple repair, and ask for references from other commercial clients, not just homeowners.
How we score the list
Our ranking weighs licensing, verified reviews, responsiveness, and the breadth of commercial work each company actually documents, not just what they claim to do. See the full ranked guide to plumbers in Irmo for how these 8 businesses compare, and read our methodology for the details behind the scoring.