A Northern Illinois service story
Built one service call at a time.
Rick Sperando and Scott Underwood started Black Diamond as a two-person plumbing company in 1999. The team grew by adding trades that homeowners repeatedly needed under the same roof.
1999 → today
The trades expanded. The home base stayed local.
Black Diamond operates from 1400 Miller Parkway in McHenry. The facility includes classroom and hands-on training space so technicians can work through equipment, controls, and service procedures away from a customer's home.
The company serves homeowners across Northern Illinois from that single business location. Service-area pages describe coverage; they do not create fictional branch offices.
Today the team answers plumbing and sewer calls alongside heating, air conditioning, electrical, ductwork, indoor-air, well, water-heater, and treatment needs.
Operating principles
Simple standards that show up in the house.
- 01
Answer when the problem happens
The dispatch line remains open around the clock.
- 02
Diagnose before prescribing
The visible symptom is the start of the investigation.
- 03
Leave the home respected
Protection, communication, and cleanup are part of the job.