"Our mission is to provide unparalleled service excellence to the community, our clients and employees through commitment to quality, cooperation and integrity."
3 Scherrs Jeremy Scherr, Safety Director, Jerry Scherr, Founder & Michael Scherr, President


EMJAY Engineering and Construction Co., Inc. is a privately owned mechanical and general contracting firm with more than 61 years of experience in the construction industry.

EMJAY was founded in 1954 by Jerome Scherr, who was president until 1984 when his son, Michael, assumed that role. Jerry now serves as a Technical Consultant and is actively involved in many projects.

EMJAY is a full service mechanical contractor with a general construction support group. EMJAY provides its construction and renovation expertise on all sizes of private and public projects throughout the Maryland, Washington, DC, Virginia and Southern Pennsylvania region. The company specializes in industrial and commercial renovation.

EMJAY possesses in-house design/build and mechanical/electrical construction capabilities and offers pre-construction analysis, consultation, specification and bid preparation. EMJAY knows how to do the work, as well as how to manage our subcontractors to do the work.

EMJAY has experienced steady and continued growth over its lifetime. We enjoy a good credit rating and a $40 million bonding capacity, along with a track record of successful projects. EMJAY has never been denied a bond, and has never defaulted on a project.

We have developed a reputation for quality craftsmanship and the ability to deliver projects on schedule and on budget. We are particularly proud of the repeat work we receive from various clients.


Staff / Leadership

Michael O. Scherr

Michael O. Scherr

Mr. Michael O. Scherr, President & Chief Executive Officer of our organization, has been in the construction industry for more than 47 years and, as Project Manager, has completed many projects throughout the State of Maryland. Mr. Scherr’s sound knowledge of the construction industry has been responsible for the successful completion of various projects within the University of Maryland School of Dentistry and Medical School Teaching Facility; U.S. Public Health Service Hospital; Crownsville Hospital Center and University Hospital, Phase I Renovations, to name a few. The aforementioned jobs ranged in contract price from $160,000 to over $3,000,000. Mr. Scherr’s ability to deal effectively in human relations has accounted for a large portfolio of satisfied, repeat clientele.

Wayne Myers

Wayne Myers

Mr. Wayne Myers, Executive Vice President & Chief Operating Officer, has over 30 years experience in the construction industry. Mr. Myers completed his apprenticeship in the plumbing trade and is now a registered Master Plumber and Gasfitter. His vast field experience as an Apprentice, Journeyman, and Superintendent has been invaluable in his transition into project management. Mr. Myers previously served as EMJAY’s Senior Project Manager and Senior Estimator for a local mechanical contractor, has experience with preparing coordinated drawings on CAD and was an instructor for the Associated Builders & Contractors’ Apprenticeship Program for over 10 years.

Steve Messier

Steve Messier

Mr. Steve Messier, Vice President of Project Management, holds a B.S. degree in Mechanical Engineering from the University of Evansville in Evansville, Indiana and has been involved with mechanical systems and construction since 1995. He began his career as an Intern with a mechanical contracting company in the Washington, DC area. Beginning in 1999, he was employed with two large mechanical contractors as both Estimator and Project Manager working on projects ranging from one to 15 million dollars mainly on design/build and prime contract work directly for an owner or engineer. He is detail oriented and has a comprehensive understanding of mechanical, HVAC and plumbing systems.

Michael A. Lohman

Michael A. Lohman

Mr. Michael A. Lohman is our Vice President/Field Operations. In this position, Mr. Lohman is responsible for overseeing all field operations and acts as liaison between our job Foremen and Project Managers. He is also in charge of EMJAY's Quality Control Program and all Project Commissioning. Mr. Lohman has been in the mechanical construction business for 36 years and is a licensed Master Plumber for Maryland, Virginia, West Virginia, Washington Suburban Sanitary Commission, Washington County and Washington, DC and holds a Master HVACR license in Maryland and Virginia. He also holds Backflow and Cross Connection Certification as well as Refrigerant Transition and Recovery Certification and has completed extensive safety training.

Jeremy M. Scherr

Jeremy M. Scherr

Mr. Jeremy M. Scherr is our Vice President of Safety. Jeremy has 25 years experience in the mechanical construction industry and has extensive safety and emergency medical training. He is a licensed Journeyman Plumber and also holds his Gasfitter's License and is certified to test all types of backflow preventers. He is a Certified Emergency Medical Technician (EMT) for the State of Maryland and a Certified Rescue Technician. He has completed extensive OSHA construction safety courses and confined space and structural collapse/rescue training. Jeremy is also a part time volunteer at Pikesville Fire Station No. 32 in Baltimore.

Marjorie C. Neumann

Marjorie C. Neumann

Ms. Marjorie C. Neumann is the Controller of our organization. Ms. Neumann holds a B.S. degree in Business/Accounting and a Masters of Science, Taxation from the University of Baltimore and is a Certified Public Accountant. She has 32 years related experience in the construction industry. Ms. Neumann's responsibilities include the accuracy and timeliness of all financial and job cost related reports. Her past knowledge and experience working with job costing and all functions of accounting in a computer-oriented environment is a valuable asset to this organization.

A. N. "Terry" Feelemyer

Mr. A. N. “Terry” Feelemyer, Project Executive for the Mechanical Division, holds a B.S. degree from the University of Maryland in Mechanical Engineering and carries a State Master HVAC License. Beginning his almost 51 years of construction experience with a consulting engineering company, his extensive plumbing and HVAC design knowledge allows him to perform design/build work and to analyze projects with a value engineering mentality. His ability to merge the engineering design to the owner’s requirements has resulted in considerable reduction of project costs while achieving the end result required by the design engineer.

David DeFelice

Mr. David DeFelice, Senior Project Manager, holds a B.S. degree in Mechanical Engineering from Lehigh University in Bethlehem, Pennsylvania and has been involved with mechanical systems and construction since 1998. He began his career as a Project Engineer/Assistant Project Manager/Assistant Estimator with the industrial group of a national mechanical contracting company in Richmond, Virginia. He transferred to the Washington, DC area in 2000 and was promoted to Project Manager. From there, he was employed with three other mechanical contractors as a Project Manager/Senior Project Manager working on projects ranging from one to eight million dollars. He has experience working on and managing projects for private clients, federal government, military, mission critical and healthcare institutions.

Armando A. Ravera, Jr.

Mr. Armando A. Ravera, Jr., Project Manager for the Mechanical Division, has 42 years experience and is a registered Master HVAC Installer and Master Plumber. He holds Gasfitter and HVACR licenses and is also a Backflow Prevention Device Technician. He has extensive experience in both estimating and running multi-million dollar mechanical projects. Armando is a Certified Plumbing Instructor and served in this capacity for Associated Builders & Contractors’ Apprenticeship Program for 5 years. His vast commercial and industrial plumbing knowledge and experience allows Mr. Ravera to handle a variety of projects in both the private and public sectors.

Kenneth Mueller

Mr. Kenneth Mueller, Project Manager, has over 15 years of experience in the mechanical and construction industry. He began his career as an HVAC Apprentice, completing the program in 2004. He has worked as an HVAC Foreman, Purchasing Agent and Project Manager in the Washington, DC area. As Project Manager, he has worked on projects ranging from one to ten million dollars both as a Subcontractor and General Contractor. Kenneth holds his HVACR Master License in Maryland, Virginia and Delaware. His extensive mechanical field experience is evident in his attention to detail and project scheduling abilities.

Charles E. Humes

Mr. Charles E. Humes, Project Manager and Estimator for the General Contracting Division, has over 48 years’ experience in the construction industry. His field experience as an Apprentice, Foreman and Superintendent has proved invaluable in his transition into project management. Mr. Humes previously served as Project Manager/Estimator for a local General Contractor and has experience in projects ranging from minor tenant fit-outs to multi-million dollar renovations and new construction. His experience and attention to detail and the owner/contractor relationship has resulted in the successful completion of numerous projects and, most importantly, client satisfaction.

Jeffrey M. Schmansky

Jeffrey M. Schmansky, Senior Estimator/Project Manager, began his career in 1977 working for his family owned plumbing and heating business. Mr. Schmansky attended construction management classes at Anne Arundel Community College which eventually led to a Master Plumber/Gasfitter license with the State of Maryland. Jeff embarked on an estimating career in 1999 and in 2000 was featured in the Plumbing-Heating-Cooling Contractors Association (PHCC) news publication as the chief estimator working for one of the 100 fastest growing private companies in America to use Estimation software. His vase experience and broad technical knowledge provided material estimation for commercial mechanical projects totaling 20 million dollars. Mr. Schmansky's project list targets a wide range of specialties including education, healthcare, multi-family and government.

David A. Rostek

Mr. David A. Rostek, Chief Estimator, has been in the mechanical contracting industry for over 35 years. He began his career with a local contractor as a Helper, became an Apprentice and advanced to a Journeyman Plumber. After several years in the field, he moved into the office and became an Estimator and Project Manager. Although Mr. Rostek’s main area of expertise, both in the field and office, is in local area hospitals, he has extensive experience in all areas of educational, industrial and commercial work. He is now a registered Master Plumber with the State of Maryland and carries a Journeyman HVAC License.

Chuck Anton

Mr. Chuck Anton, Assistant Project Manager, holds a B.S. degree in Business Administration from Bridgewater College. Chuck began his career in construction on various jobsites hanging ductwork, which then led to an internship as an estimator. After spending some time in the financial industry and before coming to EMJAY in July 2012, he spent five years working for a large Baltimore General Contractor and Construction Manager directly overseeing the mechanical contracts. At EMJAY, Mr. Anton provides support activities to the Project Managers and Estimators including but not limited to estimating new work, pricing change orders, procuring materials and equipment and coordinating Subcontractors. He has experience working on projects for private clients, the U.S. Military, hospitals and various educational institutions.



  • Aberdeen Proving Grounds
  • American University
  • Anacostia Naval Station
  • Annapolis Data Center
  • Anne Arundel Community College
  • Anne Arundel Medical Center
  • Aquaculture Research Center
  • Baltimore City Community College
  • Baltimore County Community Colleges
  • Baltimore County Public Schools
  • Baltimore Museum of Art
  • Carroll County Public Schools
  • Carroll Hospital Center
  • Catholic University of America
  • Coppin State College
  • Crownsville Hospital Center
  • Doubletree Suites
  • Ft. Detrick Biological Laboratories
  • Gallaudet University
  • Church of the Epiphany
  • Church of the Good Shepherd
  • Church of the Resurrection
  • Clifton T. Perkins Hospital
  • Coastal Sunbelt Produce
  • Defense Intelligence Agency
  • Edgewood National Guard
  • Frederick Armory
  • Georgetown University Hospital
  • Gladys Spellman Nursing Center
  • Goucher College
  • Good Shepherd Center
  • Greenspring Valley Synagogue
  • Harford Community College
  • Harford Memorial Hospital
  • Charles H. Hickey, Jr., School
  • Holy Cross Hospital
  • Howard Community College
  • Howard County Public School System
  • Kaiser Permanente
  • Kernan Hospital
  • Johns Hopkins Bayview Medical Center
  • Johns Hopkins University
  • Johns Hopkins University Peabody Institute
  • Johns Hopkins University School of Medicine
  • Lexington Market
  • Loudon Hospital Center
  • Lutheran Center
  • Marriott Inn and Conference Center
  • Martin State Airport
  • Maryland General Hospital
  • Maryland House of Corrections
  • Maryland Motor Vehicle Administration
  • Maryland Public Television
  • Maryland School for the Blind
  • Maryland School for the Deaf
  • Maryland State Highway Administration
  • Maryland State Police
  • Montgomery General Hospital
  • Morgan State University
  • National Aquarium in Baltimore
  • National Institutes of Health
  • National Naval Medical Center
  • National Railroad Passenger Corp. (AMTRAK)
  • NER Israel Rabbinical College
  • Old Otterbein United Methodist Church
  • Pall Corporation
  • Perry Point VA Hospital
  • Prince George's Hospital Center
  • Prince of Peace Presbyterian Church
  • Random House
  • Roland Park Place
  • Rosewood Center
  • St. Agnes Hospital
  • St. John Lutheran Church
  • St. John's College
  • St. Joseph Medical Center
  • St. Vincent's Center
  • Salisbury Armory
  • Shady Grove Adventist Hospital
  • Sinai Hospital of Baltimore
  • Spring Grove Hospital Center
  • Springfield Hospital Center
  • Sprint Communications Company
  • State of Maryland Department of General Services
  • State of Maryland Department of Health & Mental Hygiene
  • State of Maryland Department of Veterans Affairs
  • Suburban Hospital
  • Towson University
  • Union Hospital of Cecil County
  • University of Baltimore
  • University of Maryland Baltimore
  • University of Maryland Baltimore County
  • University of Maryland Biotechnology Institute
  • University of Maryland College Park
  • University of Maryland Medical System
  • U.S. Naval Academy
  • Washington Adventist Hospital
  • Washington Ballet
  • Washington Cardiovascular Institute
  • Washington Hospital Center
  • Washington Navy Yard