OUR TEAM

Barret Williams has over 25 years of experience in the Architectural/Engineering/Construction industry and, in 2021, joined WBS, where he leads MEP Design services on behalf of the Company. Mr. Williams is also responsible for coordination with owner’s and other disciplines, including architects, structural engineers, electrical engineers, and others as needed, during the design and construction contract administration phases. With his significant field and quality control experience, Mr. Williams also provides commissioning services.

Prior to joining WBS, Mr. Williams was most recently with Hoffman and Hoffman where he was responsible for HVAC equipment selection, sizing and sales for new construction and HVAC replacement projects. His extensive knowledge of systems and components spans multiple technologies, including chilled water systems (water cooled, air cooled, magnetic bearings, gas fired), water source heat pumps (tower and geothermal loops), VRF (variable refrigerant flow systems), pool units, DOAS (dedicated outdoor air systems), air cooled DX, and evaporative cooled. He is skilled at estimating and laying out equipment types for projects in multiple building segments, including educational, office, medical, laboratories and military.

Mr. Williams holds a Bachelor of Science in Mechanical Engineering from North Carolina State University.

Joel McKellar leads commissioning, retro-commissioning and recommissioning services, high-performance sustainable design consulting and energy auditing services. He plays a leadership role in advancing the definition of sustainable buildings to include occupant health and well-being with a focus on indoor air quality. He is a Certified Building Commissioning Professional, a LEED AP and Living Futures Ambassador and, for many years, played a key role on USGBC’s LEED Energy and Atmosphere Technical Advisory Group. Mr. McKellar recently completed the commissioning of the 220,000-square-foot Lucy Beckham High School in Mount Pleasant, SC and The Citadel’s new Bastin Hall, where he also provided air quality testing. He is currently commissioning the new International African American Museum for the City of Charleston, MUSC’s College of Pharmacy addition and the renovation of the MUSC’s Colbert Library. He is also providing LEED consulting services for the Tomochichi Federal Building and Courthouse in Savannah and the Joint Base Charleston Readiness Center in Moncks Corner, SC.

Mr. McKellar has over 20 years of experience in optimizing the performance of buildings from design through occupancy and has commissioned, certified or audited over 30 million square feet of commercial, industrial and higher education building stock. Prior to joining WBS, Mr. McKellar served as Associate Director of Green Building Services at Harvard University where he was responsible for strategic planning, project management and policy guidance for the sustainable design, construction and operations of Harvard University's 27-million-square-foot campus. He co-authored the Strategic Sustainability Plan at the Harvard Kennedy School of Government, updated the University-wide Green Building Standards and provided technical reviews for the Harvard Green Revolving Fund. Prior to his work at Harvard, Mr. McKellar was a Research Strategist for the architectural firm LS3P ASSOCIATES LTD. in Charleston, SC.

Mr. McKellar holds a Bachelor of Arts in Architecture from Clemson University.

Dennis Knight founded Whole Buildings Systems, LLC in 2010 after having owned an engineering firm and a construction company and serving as a Principal at Liollio Architecture in Charleston, South Carolina. He is a registered mechanical and fire protection engineer, an ACG certified Commissioning Authority, an ASHRAE certified Building Energy Modeling Professional (BEMP), a LEED NC and EB O&M Accredited Professional and a Building Performance Institute (BPI) certified Building Energy Analyst (BA) and Envelope Professional (EP). He was also instrumental in the development of the ASHRAE Building EQ tool.

He has over 46 years of experience in the design, construction, operation and maintenance of high-performance buildings and has served in numerous capacities for the American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) including as Vice President of the Board of Directors, an ASHRAE Director at Large and an ASHRAE Distinguished Lecturer. He is currently the President of the ASHRAE College of Fellows and was instrumental in creating the ASHRAE Epidemic Task Force to address the Covid-19 pandemic.   

Mr. Knight’s expertise lies in Building Information Modeling (BIM) and Integrated Building Design. He chaired the ASHRAE BIM Multi-disciplinary Task Group, where he was the liaison to the International Building Smart Alliance, and he founded the annual ASHRAE Building Performance Analysis Conference, which he chaired for its first 5 years.

During his career, Mr. Knight has commissioned hundreds of new buildings and audited, recommissioned or retro-commissioned over 100 million square feet of existing commercial, federal and industrial building stock. He provides MEP drawings and specification for major HVAC retrofits using Revit and provides whole building energy simulation analysis using Trane Trace 3D Plus.

Mr. Knight frequently lectures (virtually and in person) in the US and abroad on high-performance building tools and technology and has authored numerous publications and white papers on a variety of technical topics. During the Covid-19 pandemic, he was asked to address the US House Energy and Commerce Committee Staff and was interviewed by multiple national news media. He has developed curriculum and teaches on Building Information Modeling (BIM), Integrated Building Design, Life Cycle Cost Analysis, ASHRAE 90.1 and IECC energy code compliance, energy management for historic structures, and energy modeling and commissioning of energy using systems.

Mr. Knight’s vision for Whole Building Systems is to assist owners, architects, contractors and facility management professionals to adopt new tools and process improvement strategies that will result in the design, construction, operations and maintenance of high-performance buildings that meet sustainability and resiliency goals, including air quality, carbon neutrality and resource efficiency.

Mr. Knight holds a Bachelors of Science in Physics from the College of Charleston.

Carol joined our team in 2023 and leads HR, accounting, payroll, and other logistical support services on behalf of WBS. She is responsible for launching new logistical tools that have improved company accounting processes and streamlined our financial reporting and analytics. She routinely supports business development activities, and has started supporting project work across all of WBS service lines to better understand the work we provide to our clients.

Emily joined the WBS team in 2024 as a recent graduate of Appalachian State University with a BS in Building Science – Sustainable Building Systems and a minor in Sustainable Development.  She has supported Green Globes/LEED consulting and indoor air quality testing efforts at WBS in her role as a High Performance Building Specialist.

At ASU, she was a key member in developing the University’s 2023/24 Solar Decathlon entry, designed and built to meet Zero Energy Ready standards. In this capacity she organized and participated in charrettes to gather professional input and better understand the client’s needs for the Watuaga Community Housing Trust project. She supported both design and construction management efforts for the project, including design consultation, construction estimating, and related project services.

Tom Smith has over 20 years of project management, HVAC, information technology, construction, and facilities experience. Prior to joining WBS in 2022, he managed the engineering, installation, and commissioning of approximately $1 million of concurrent building automation projects, including laboratory, retail, office, hotel, stadium, data center, communication, financial, and manufacturing locations of up to 1.5 million square feet. Specifically, his projects included energy optimization, re-commissioning, software development, smoke control, refrigerant leak alarming, air quality, AutoCAD control drawing, engineering, and custom controller development, and he worked with a team of 50 internal and contract team members and participated in and facilitated training on safety and technical topics.

Mr. Smith is a Green Globes Professional, a Building Performance Institute Building Analyst & Envelope Professional, holds eight ASHRAE Certifications in HVAC Commercial Controls Systems, and has both a National Commercial General Contractor and Mechanical Contractor License.

Mr. Smith received his Bachelor of Science in Information Technology from University of Central Florida.