Professional Installation
Plumbing Installation Services
From water heaters to whole-home repiping, Darwyn's Plumbing delivers professional installation services that are built to last. Over 27 years installing plumbing systems across the St. Louis Metro-East area.
Installation Services
Every installation is performed to current Illinois plumbing codes by our licensed, experienced technicians. We pull permits when required and coordinate inspections so you're fully covered.
Water Heater Installation
Tank and tankless water heater installation. We carry top brands and size the unit correctly for your home's hot water demands.
Sump Pump Installation
Protect your basement from flooding with a properly sized sump pump. We also install battery backup systems for power outages.
Plumbing Fixture Installation
Faucets, sinks, toilets, showers, bathtubs — we install all fixture types in kitchens and bathrooms.
Water Softener Installation
Hard water damages pipes and appliances. We install whole-home water softeners and reverse osmosis filtration systems.
Whole Home Repiping
Old galvanized or polybutylene pipes? We replace entire home plumbing systems with modern copper or PEX piping.
Garbage Disposal Installation
New installation or replacement of InSinkErator, Moen, and other leading garbage disposal brands.
Gas Line Installation
New gas line runs for appliances, grills, fire pits, and generators. Licensed for residential and commercial gas work.
Sewage Ejector Pump
Below-grade bathrooms and laundry rooms need ejector pumps. We size, install, and test to local code requirements.
Bathroom & Kitchen Remodeling
Planning a bathroom or kitchen renovation? Darwyn's Plumbing handles the plumbing rough-in and finish work so your remodel goes smoothly. We coordinate with your contractor or manage the plumbing side of your project from demo to final inspection.
Our remodeling services include moving drain and supply lines, installing new tub/shower systems, setting toilets and vanities, running new water lines to refrigerators and dishwashers, and upgrading to modern fixtures.
- ✓Bathroom gut-and-remodel plumbing
- ✓Kitchen sink and dishwasher installation
- ✓Tub-to-shower conversions
- ✓Double sink and undermount installations
- ✓Countertop and fixture coordination
- ✓Full rough-in for additions and ADUs
Get a Free Installation Estimate
Tell us what you need installed and we'll schedule a time to assess the job and provide a detailed, flat-rate quote — no obligation.
Installation Services in Belleville, O'Fallon & Metro-East IL
From a new water heater installation in a Belleville home to a complete whole-home repipe in Edwardsville, Darwyn's Plumbing has been the Metro-East area's trusted plumbing installation contractor for over 27 years. We serve homeowners, property managers, contractors, and businesses across Belleville, O'Fallon, Granite City, Edwardsville, Collinsville, Fairview Heights, Shiloh, Swansea, Alton, and all of St. Clair and Madison counties.
Every installation we perform is done to current Illinois plumbing code and local municipal requirements. We pull permits when required, coordinate inspections, and document the work properly — protecting both you and your home's resale value. We carry most common installation parts and equipment on our trucks, allowing us to complete the majority of residential installs in a single day.
Whether you're updating a 1960s Belleville home with a new high-efficiency tankless water heater, adding a battery backup sump pump before storm season in Granite City, or running a gas line for a new outdoor kitchen in O'Fallon, our experienced licensed plumbers handle it efficiently and correctly the first time.
Typical Installation Costs
All pricing is estimated — free on-site quotes provided before work begins.
Plumbing Installation FAQ
Do I need a permit for a water heater replacement in Illinois?+
In most Illinois municipalities, a permit is required for water heater replacement. We handle the permit process and coordinate the required inspection on your behalf, so you don't have to navigate the paperwork.
How long does a water heater installation take?+
A standard tank water heater replacement typically takes 2–3 hours. A tankless water heater installation takes 4–6 hours due to the additional gas line, venting, and electrical work involved.
Tank vs. tankless — which is right for my Belleville home?+
Tank water heaters are less expensive upfront ($950–$1,500 installed) and simpler to maintain, but they run out of hot water during heavy use and cost more to operate. Tankless heaters cost more upfront ($1,800–$3,500+) but never run out of hot water and use 20–30% less energy. For homes with 2+ bathrooms and high hot water demand, tankless is usually the better long-term investment.
How do I know if my sump pump needs replacing?+
Signs your sump pump is failing: it runs but water level doesn't drop, it runs constantly, it makes unusual grinding or rattling noises, or it simply won't activate when water enters the pit. If your pump is over 7–10 years old, proactive replacement before storm season is strongly recommended.
Can you run a gas line for an outdoor kitchen or generator?+
Yes. We are licensed for residential and commercial gas line work in Illinois. We run new gas lines, size them correctly for the appliance BTU requirements, pressure test the line, and pull the required permits. Common projects include outdoor grills, fire pits, generators, and garage heaters.
Do you install plumbing for home additions or ADUs?+
Yes. We handle full plumbing rough-in for home additions, accessory dwelling units (ADUs), basement finishing projects, and garage conversions. We work directly with your general contractor or can manage the plumbing side independently.
Ready to Schedule an Installation?
Serving Belleville, O'Fallon, Granite City, Edwardsville, Cahokia and the entire Metro-East area. Free estimates on all installations.
Call (618) 337-9322