Community Involvement

The company has been an active supporter of helping the hospital meet the growing healthcare needs of the community for over 15 years, and is recognized as a FMH Corporate Honor Roll partner. In addition, Matt Warner has generously donated his time and resources to serving as a member of the Business and Industry Committee.
For nearly 50 years R. W. Warner has been an active supporter of Rotary International through membership in its local chapters, Rotary Club of Frederick and Rotary Club of Carroll Creek. Rotary International is widely known for its efforts to eradicate polio worldwide and the local clubs have funded hundreds of projects and volunteered countless hours to fulfill their motto of ’Service Above Self’.

R. W. Warner recognizes that a healthy economy and robust business climate is an integral part of a thriving community. We proudly lend our support to the local Chamber as a Silver Trustee in furtherance of their mission of connecting business and community through leadership, advocacy, and education.
- Hood College
- Mt. Saint Mary’s University
- St. Johns Catholic Prep
- Frederick County YMCA
- Hospice of Frederick County
- Delaplaine Visual Arts Center
- St. Maria Goretti High School
- The Barnesville School
- Christmas Cash for Kids
- Mother Seton School
- Museum of Civil War Medicine
- Oakdale High School Athletics
- Spires Lacrosse Club
- St. Judes Children’s Hospital
- Mental Health Association
- Frederick Alliance for Youth
- Wounded Warriors
- Boys and Girls Club of Frederick
- Way Station
- Special Olympics
- Boy Scouts of America
- Trinity School
- Banner School
- Friends of Catholic Education
- TJ High School Athletics
FAQs
Find answers to common questions about our services and how we can assist you.
R.W. Warner, Inc. is a family-owned construction and mechanical contracting firm based in Frederick, Maryland, offering plumbing, HVAC, electrical, and general contracting services across multiple industries.
We serve a wide range of industries, including residential, commercial, industrial, institutional, and government sectors. Our team is equipped to handle everything from home services to large-scale mechanical and construction projects.
R.W. Warner, Inc. is located in Frederick, Maryland, where it has maintained a strong presence since its founding. This central location allows the company to efficiently serve clients across Western Maryland, Northern Virginia, and parts of West Virginia, supporting a wide range of residential, commercial, and industrial projects.
Our company comprises several specialized divisions:
- Williams Electric – Electrical contracting services
- Warner Mechanical – HVAC and plumbing solutions
- Warner Construction – General contracting and construction management
- Kaempf & Harris Sheet Metal – State-of-the-art sheet metal fabrication and installation services
Our website serves as a central hub to direct you to the appropriate division. To connect with the appropriate division for your project, please contact us through one of the following methods:
Phone: (301) 662-5387
Email: info@rwwarner.com
Contact: Contact Us
Our team will direct your inquiry to the relevant division, be it Warner Construction, Warner Industrial, Warner Mechanical, Warner Service, or Kaempf & Harris to ensure your project's specific requirements are met efficiently.
Our main office is situated at : 217 Monroe Avenue
Frederick, Maryland 21701 where we coordinate our operations and support projects across the region.

