Mechanical, Electrical, Plumbing Engineering

Fuss & O’Neill provides mechanical, electrical, and plumbing (MEP) and energy consulting engineering services. We excel at complex, challenging and unique building projects, both large and small, from new construction to renovation. Our comprehensive services cover all phases from design, construction to commissioning. We have long-standing relationships with architectural, municipal, state, federal, manufacturing, and institutional clients. We have the knowledge and experience to provide design and construction support services you need for your building project.

Our team consists of Professional Engineers (PE), LEED AP (Leadership in Energy and Environmental Design) accredited professionals, and The Association of Energy Engineers (AEE) certified Energy Managers (CEM), Green Building Engineer (GBE), Building Energy Simulation Analyst (BESA), and Certified Building Commissioning Professional (CBCP).


Our design work experiences includes field investigations, evaluations of existing systems, heating and cooling load calculations, and electrical load analysis, as well as equipment selection and layout. We provide bid and contract documents, specifications, opinions of cost, and construction support services. We also perform third party reviews of MEP plans and computations prepared by others.

Our HVAC designs go beyond the conventional practice of equipment selection and design of air distribution and piping are especially strong in the application of humidity control technologies. Through the use of appropriate control sequences and proper configuration of HVAC equipment, we are able to satisfy multiple design objectives for both new and retrofit/replacement systems. We can perform forensic or diagnostic services associated with building performance and specialize in “problem based retro-commissioning.”

We have been providing energy planning and management services to municipal, state, federal, industrial, institutional, and utility clients since the late 1970s and have extensive experience in energy analysis. In addition to performing our own analyses and design work, we also act as a quality control consultant for utility companies. We are a member of the USEPA’s Combined Heat and Power Partnership program, participate in state and federal utility incentive programs, and prepare Measurement and Verification plans for cogeneration installations.

Our LEED Accredited Professionals provide cutting-edge designs that combine the greatest energy conservation with truly livable interior spaces. Our Certified Energy Managers evaluate cost-effective solutions to reduce energy consumption and optimize performance. Our services range from natural gas conversion to developing cogeneration, as well as fuel cell, biomass, geothermal, hydropower, wind, and solar facilities.


Examples of our experience include:


  • Heating, Ventilation, and Air Conditioning (HVAC) Design
  • Campus Steam and Chilled Water Systems
  • Central Plant Upgrade
  • Commercial Kitchen Systems Design
  • Direct Digital Controls Design
  • Power Distribution Design
  • Un-interrupted Power Supply (UPS) and Backup Power Design
  • Interior and Site Lighting Design and Controls
  • Fire Alarm System Design
  • Lightning and Surge Protection Design
  • Indoor Air Quality (IAQ) Analysis
  • Commissioning of MEP systems


  • Building Energy Audit/Assessment
  • Energy Performance Modeling/ Benchmark
  • Photovoltaics (PV) design
  • Lighting System modeling
  • Retro Commissioning
  • Energy Management Systems Upgrade
  • Power metering and Data analysis/ Measurements &Verifications (M&V)
  • Combined Heat and Power
  • Microgrid design
  • Quality Control Consulting for Utility Incentive Programs


Milford Municipal Building Energy Services

North Coventry Fire Department

Comm. College of RI Energy Saving Upgrades

UConn Steam Distribution System

Middle School Electric to Gas Fuel Conversion

Solar Photovoltaic Systems

Contact Us

  • Call us toll free at 800-286-2469
    146 Hartford Road, Manchester, CT 06040