Your Business Depends On Reliable Plumbing, And Our Team Delivers Solutions That Keep Your Operations Running Smoothly.
Commercial properties require durable, efficient, and code-compliant plumbing systems to operate without interruption. At NJM Mechanical & Contracting, we offer comprehensive commercial plumbing services for businesses across Long Island, Nassau County, and Suffolk County.
Whether your building needs routine maintenance, emergency repairs, or full system upgrades, our licensed professionals deliver fast, high-quality service tailored to your operational needs.

Full plumbing systems for new construction, renovations, and commercial build-outs—including supply lines, drains, fixtures, and utility connections.

Repair of damaged or corroded pipes, leak detection, and complete pipe replacements designed for heavy commercial use and long-term durability.

Clearing of clogged drains and sewer lines using commercial-grade equipment, including camera inspections for accurate diagnostics.

Installation and replacement of high-capacity commercial water heaters and boilers sized specifically for your building’s hot water demand.

Installation, maintenance, and certified testing of backflow prevention devices to ensure compliance with Long Island regulations.

Expert Plumbing Solutions Backed
by Over 33 Years of Experience
Why Businesses Across Long Island Trust NJM for Commercial Plumbing
Reliable service, expert workmanship, and fast response times tailored to commercial needs.
All commercial plumbing work is performed by fully certified and insured technicians who understand commercial code and safety standards.
We work efficiently and cleanly, scheduling work around your business hours when possible to avoid downtime.
From hydro-jetting to camera inspections, we use the latest technology to diagnose and resolve issues quickly.
Every installation and repair is supervised for accuracy, compliance, and long-term performance.
Offices, restaurants, retail stores, industrial buildings—our team adapts to any commercial layout or requirement.
Clear, upfront pricing with no hidden fees or unnecessary add-ons.
Water Heater & Boiler Safety Testing
Assessment of temperature controls, pressure relief valves, gas/water connections, and venting to prevent hazards and improve efficiency.
Fixture & Appliance Safety Checks
Inspection of water heaters, boilers, valves, shut-offs, and plumbing fixtures to ensure proper operation and safe performance.
Leak Detection & Line Evaluation
We use advanced diagnostic tools to locate leaks, pressure issues, corrosion, and worn components before they evolve into major problems.
Emergency Shut-Off Valve Testing
Ensuring all plumbing shut-off valves function properly in the event of leaks or system failures.
Drain, Vent & Pipe System Assessment
A full review of your home’s plumbing infrastructure — drains, vents, supply lines, and connections — to ensure proper flow and system health.
Code Compliance Review
We verify that your plumbing system meets all Long Island, Nassau, and Suffolk County regulations — essential for renovations, additions, or property sales.
Trusted Plumbing Expertise for Long Island Homes & Businesses
Our Plumbing Safety & Inspection Services Include:
NJM provides advanced inspection, leak detection, and safety evaluations to keep your plumbing system running efficiently, safely, and fully compliant with local codes.

Find HVAC Services Near You!
Service Area Links:
- Long Island
- Nassau County
- Suffolk County
What Our Long Island Clients Are Saying...
Kris
I couldn’t recommend Neil enough! From start to finish him and his team were professional, efficient and experienced. We had a job pulling up rocks and putting top soil down which I know can be a tedious job. We appreciate the work and look
Evelyn Powers
We had an ongoing issue with clogs. My daughter woke up to flooding in her bedroom from her toilet, which was not fun! This was our first time having NJM in our home. Neil was knowledgeable and gave us several options. we chose to have him use the camera to get to the root of the problem. He was able to pinpoint several issues and was able to fix clog and clean out the pipes. Neil and his crew were very professional,
Irene Cheung
I contacted NJM Mechanical because I didn’t have hot water anywhere in my house. Neil was able to diagnose the issue and get to work. My navien tankless water heater is only a year old and still under warranty. Instead of waiting on Navien to send the part so the issue can be corrected, Neil went out, found the part, purchased it,
William Lo
Great experience. Neil came out and took the time to explain everything thoroughly. He was able to fix all the errors on our Navien and have it back up and running. Following up a week later. Neil and Mike came out to redo the Navien system for proper instillation.
Unfortunatley, after there was a gas leak with our Navien system. Neil was able to get
James Farnworth
Neil from NJM was able to get my ac system up and running when others could not. He was honest with me right from the beginning and all costs were discussed before repairs began. Additionally, Neil spent time explaining to me how my system operates and the things I could do to help it run at peak performance. It was quite refreshing to experience a service technician who demonstrated the uppermost
Raul Chardon
Honest professional full of knowledge not BS. Takes pride in his craft and is a master of it.

Commercial Plumbing Services on Long Island
Professional plumbing installation, maintenance, and repair for offices, restaurants, retail spaces, and commercial buildings across Nassau and Suffolk County.
Need fast, emergency commercial plumbing service? Our licensed technicians are ready to assist 24/7.






