M & J Underground, Inc.

Category

Plumbing

Address

26603 South Governors Highway, Monee, IL 60449

Phone

(708) 534-6434

Website

mjunderground.com

Opening hours

Mo-Fr 07:00-16:00

Data checked

November 6, 2026 (OpenStreetMap)

Before You Hire

Facilities usually schedule plumbers yearly for backflow tests and water heaters, plus repairs as needed. Ask:

• Do you take commercial work, and do you service buildings like ours?
• Can you send a certificate of insurance naming us as additional insured?
• Are you licensed in this state, and may we have the license number?
• Do you have certified backflow testers, and do you file reports with the water utility?
• Do you offer 24-hour emergency service, and what is the call-out fee?

All 8 questions to ask →

Hiring Tips

• Label every main and zone water shutoff before you need them.
• Your water utility usually sets the backflow test deadline; keep its notice on file.

Getting several quotes? Line them up in the quote comparison tool and check the contract checklist before you sign.