Our History

1956

Jack Stevenson bought Hoffman Brothers Bar and Restaurant Supply

1959

Renamed Hoffman Brothers Bar and Restaurant Supply to Hoffman Chemical

1961

Cleaners at IBM asked Jack to take over cleaning services

1961

Jack established DnS Janitorial to offer commercial cleaning services

1986

Scott Stevenson, Jack’s son, began working at DnS Janitorial

1998

Expanded to Oshkosh and Appleton, Wisconsin

2000

Scott Stevenson took over as owner and CEO of DnS Janitorial

2001

Reached 500 employees

2005

Scott rebranded DnS Janitorial and Hoffman Chemical to KleenMark

2006

Expanded to Milwaukee, Wisconsin

2007

KleenMark successfully obtained CIMS With Honors certification

2008

Expanded to Wausau, Wisconsin

2011

KleenMark successfully obtained CIMS Green Building With Honors certification

2015

Expanded into Minnesota and Illinois

2022

Expanded into Arizona

2023

Expanded into Pennsylvania

2023

Exceeded 1000 employees

2023

KleenMark successfully obtained CIMS Green Building Advanced by GBAC With Honors certification

2024

Expanded into Utah

2025

We continue to:

  • Find unique solutions for each client
  • Test new technology
  • Continue our incredible client retention
  • Provide opportunities to our KleenMark associates
  • Delight our clients