Our people

Barry Martin | Director

  • Barry has an extensive background with the CSIRO as a Principal Research Scientist and brings to the team unique problem solving expertise.

    Over the years Barry has forged extensive experience in the area of public utilities, commercial buildings, government and health facilities. Barry is committed to finding effective solutions to complex problems.

Jim Hatzimanolis | Director

  • Jim has over 30 years of relevant experience in the building industry, during which time he has occupied a range of roles, including Project Director for multidisciplinary projects and Lead Electrical Engineer for numerous complex facilities. Jim’s experience is capacious with a strong emphasis on health, education, residential/ mixed use, aged care and government commissions.

    Jim is the founder of JHA in 1995 and continues to be actively involved in the administration of the business, while being an active hands-on Director / Project Leader.

Marc Estimada | Director

  • Marc is a Director and Lead Building Services Engineer experienced in project design consultation, technical design and documentation for a diverse range of multidisciplinary projects. Marc has an acute sense of client requirements and sophisticated project management and delivery methodology.

    Marc's extensive experience includes university/tertiary education, early learning to secondary education, high-end/high-rise/boutique residential, commercial, government/high-security facilities and healthcare.

Alex Hole | Director

  • Alex brings over 20 years experience in design consulting in the built environment. A mechanical engineer by background Alex has played key roles in the design and delivery of multidisciplinary services engineering across multiple sectors including commercial, residential, healthcare, arts & culture and science & research buildings.

    Passionate about design and inspired by the magic that comes from the collaboration of teams, Alex brings a creative and inclusive mindset to consulting engineering.

Hadi Jalgha | Director

  • Hadi has over 20 years’ experience in the building engineering services field and HVAC services design. With a strong emphasis on project leadership, practical solutions and quality assurance, Hadi expertly leads the JHA mechanical team to ensure all core elements of a project are met, to the highest standards.

    Hadi's comprehensive project experience encompasses a wide range of sectors such as government, defence, health, education, residential and mixed-use, commercial, retail and transport sectors.

Tian Song | Director

  • Leading the JHA Queensland team from our Brisbane office, Tian is an accomplished Chartered mechanical engineer with RPEQ and NER endorsement. Tian has a broad range of experience within the building services industry, undertaking mechanical HVAC design and specializing in the management and delivery of multidisciplinary projects.

    Tian has a strong focus on client engagement and working collaboratively within project teams to develop robust and well thought out engineering solutions for projects. His project experiences include healthcare, education, defence, commercial, retail, auditing, residential, industrial, hospitality and sporting facilities amongst others.

Ben Cook | Director

  • Ben is a Chartered mechanical engineer with a wealth of experience in the design of mechanical building services systems with a key focus in healthcare projects.

    Ben’s extensive hands-on mechanical experience has provided him with a solid understanding of systems for across various building types.

Diego Montelvere | Director

  • Diego has over 20 years of valuable experience in the hydraulic services industry. He has worked in the consultancy field for over 15 years, and prior to this, Diego worked as a plumbing sub-contractor for 6 years, giving him practical experience in the construction industry.

    Diego's wide range of expertise extends over sectors such as health, commercial, residential, hotels, retail, entertainment, education, public buildings and transport infrastructure.

Brenton Burrows | Director

  • Brenton has over 20 years experience in the building industry, where he has applied vital design and practical skills through his time consulting and contracting.

    Brenton’s diverse abilities and innovation provide valuable insight at every level, while consistently delivering exceptional service with a client focus. His broad experience includes infrastructure, defence, health, public works, commercial and residential developments.

Chris Hadjiyiannis | Director

  • Chris has a wealth of experience across wet and dry fire protection and mechanical services. A FPAA Fire Systems Design Accredited Practitioner, Chris has extensive experience in all areas of design, documentation, project management and commissioning for a wide range of projects including health, aged care, residential, hotels, commercial and government facilities.

    An expert communicator and multidisciplinary project team leader, Chris leads the JHA fire services team.

Jeffrey Ng | Director

  • Jeffrey has over a decade of extensive experience in the building services industry and is actively involved in the HVAC & ESD sectors. He has worked in various sectors including healthcare, large scale mixed used developments, NABERS rated commercial buildings and institutional buildings.

    With notable professional accreditations such as CPEng, NER, CBD and NABERS, Jeffrey’s experience across both ESD and HVAC design provides him an in-depth understanding of the practicalities of design and cost of construction to meet the demand of the evolving “green” building market.

Kosma Tzannes | Director

  • With over 15 years of consulting experience in the electrical building services and electrical infrastructure industry, Kosma’s experience ranges across a diverse array of projects including L3 ASP substation design, overhead and underground high and low voltage design, authority asset relocation (electrical & telecommunication), subdivision master planning, street lighting, as well as complete electrical and telecommunication building services design works.

    Kosma leads the JHA High Voltage/ Level 3 ASP infrastructure team with vast practical experience and knowledge across Ausgrid, Endeavour Energy, Essential Energy, main telecommunication providers, and infrastructure authorities.

Nathaniel Siely | Director

  • Nathaniel is a Chartered electrical engineer who has been operating in the built environment sector for more than 15 years. Now based in our Brisbane office, Nathaniel brings a broad range of experience delivering projects within Australia and the UK.

    His primary project sector experience includes healthcare, education, defence, industrial, aviation and rail. Nathaniel relishes the challenge of working through difficult projects to deliver his clients their desired outcomes. He is a strong believer in clear, regular communication to keep expectations aligned and ensure everyone is moving in the same direction.

James Farrah | Director

  • James joined our Queensland office in its infancy as the fifth employee overall and supports an office that now has grown to have over 50 local staff.

    A mechanical engineer by background, James is a Chartered Engineer that holds RPEQ registration and leads JHA across a variety of sectors including healthcare, aged care, commercial, and residential. As a team lead, James prefers to stay actively involved in projects from start to end, ensuring our clients expectations and project requirements are met.

Darren Campbell | Director

  • With eight years hands-on experience as a Licensed Plumber, four years as the Principal Hydraulic Officer at the Queensland Department of Public Works and twenty five years in the consulting field at Principal/Director level, Darren has a broad experience base in hydraulic engineering with application in design, documentation, specification and construction quality control for all project types.

    Darren's project experience is truly extensive and embraces every market sector for the full range of hydraulic services.

Jarrod Grimshaw | Director

  • With over 15 years of experience, Jarrod had been involved in a variety of projects across the health, residential, aged care, education, retail, commercial, defence, and data sectors as both a design and site-based engineer. After graduating from the University of Sydney with First Class Honours, Jarrod has established his engineering career designing and detailing a variety of structures constructed from steel, reinforced concrete, post-tensioned concrete, and timber. These designs have utilised a variety of specialist engineering software packages to suit the design scenario.

    An unwavering drive to understand complex design challenges and deliver quality structural solutions motivates Jarrod to work on high quality projects and deliver excellent client outcomes.

Cheryll Karim | Operations & HR Manager

  • Cheryll is JHA’s Operations & HR Manager with a strong background in the areas of Human Resources, Accounting, Risk Management, and Audit services. She has over 18 years’ of experience in Management Accounting and Financial Management.

    Her role involves the overall operational management of JHA. She works closely with our Directors and Senior Group Leaders to assist with the effectiveness of the business.

    Cheryll ensures the compliance of our management systems. Her core competence lies in operations & financial management, analysis, cost reduction and performance, as well as the implementation of standards and policies.

Nemesio Biason Jr | Senior Associate / Civil Group Manager

  • Nemesio is a Chartered civil engineer with a proven track record delivering complex projects throughout Australia. He has a deep understanding of the principles of holistic design including the initial feasibility stage, through to detailed design, construction stage, and superintendent services.

    With over 25 years’ experience, Nemesio has consistently provided high-performance civil engineering outcomes for projects ranging from small to largescale developments in a variety of sectors including infrastructure, residential, commercial, industrial, WSUD, flood studies, and significant land developments.

    Nemesio brings invaluable technical, leadership and management skills and a proactive, team-focused working style in his multifaceted role as JHA’s Civil Group Manager and Senior Associate Engineer.

Jorge Reverter | Acoustic Group Manager

  • Jorge brings over 20 years of comprehensive experience in the acoustic consultancy field in Australia and Spain.

    His experience includes a broad spectrum of acoustics projects covering: transport infrastructures, land planning, room acoustics, building acoustics, noise and vibration control for building services, environmental noise control and assessments, programming and computer modelling.

George Petropoulos | Vertical Transport Group Manager

  • George has over 27 years’ in-depth vertical transportation knowledge, based on his extensive experience in working with industry leading VT companies such as Kone, Otis, and Liftronic.

    George has a wide range of experience on projects within various building sectors such as health, residential, retail, commercial, industrial, transport, government and public domain.

    Complimentary skill sets in building design through Traffic Analysis, System Interfacing & Integration and design aesthetic for new buildings and modernisation solutions for existing buildings. Management capability of service and maintenance for existing building Vertical Transport Capital Equipment.

Alex Frew | Audio Visual Technology Group Manager

  • Alex has more than 20 years’ experience in the audio visual technology industry from stage production and crewing through to installation and design. This practical experience is further supported by a Masters of Architectural Science (Audio and Acoustics).

    Alex has a passion for technology systems which are designed to improve and simplify the people’s lives.

    Focused on the user experience, Alex looks to provide solutions which are fit for each customer’s need and purpose.

Joanna Pan | Specialist Lighting Group Manager

  • Jo brings a unique approach to the creative lighting team, attributable to her background in interior architecture. Her extensive training within spatial design has proved to be a valuable asset, with her ability to comprehend and visualise illumination clearly in 3D spaces and apply such techniques into lighting design.

    Jo continues to push the boundaries of light and darkness in her design, providing striking lighting installations for our clients. Jo’s experience in the building services industry is extensive, with hands-on involvement in entertainment, hospitality, high-end residential, heritage and commercial fit-out sectors.

Stefano Veglia | Specialist Lighting Principal

  • The craft of sculpting environments with light is both a passion and a profession for Stefano. Working at the intersection of technology and art, he leads projects that seamlessly integrate lighting into architectural spaces. His proficiency in visual planning and spatial awareness enables him to create immersive experiences that enhance the aesthetic and functional qualities of a structure.

    Stefano’s journey in the lighting industry, spanning over two decades, has been marked by a commitment to design excellence and efficiency. He has accomplished a spectrum of projects across Europe, Asia and the Asia Pacific, where he honed his skills in lighting design. Now Stefano continue to pursue the aspiration of revealing the true essence of architecture, one beam of light at a time. 

Lawrence Yu | ESD Group Manager

  • With over 19 years in ESD consulting, Lawrence is a seasoned professional specializing in providing bespoke sustainability solutions for the built environment. Lawrence combines deep expertise in ESD regulations and uses cutting-edge benchmarking tools like Green Star, NABERS, NatHERS, and WUFI to design buildings that optimize energy usage, reduce carbon emissions, and enhance the overall comfort and wellbeing of building occupants.

    From hotels and aquatic centres to commercial and residential developments, Lawrence has a proven track record of delivering exceptional results across diverse sectors. Having served on the BASIX Thermal Comfort Protocol Working Group, the GBCA Academy Advisory Group, and the ABSA Technical Advisory Committee, Lawrence is committed to staying at the forefront of his profession and driving progress in the ESD industry.

Tommy Sailing | Senior Associate / ICT Group Manager

  • Tommy is a highly experienced engineer specialising in next-generation communications, integrated smart buildings technologies and electronic security.

    Adopting a ‘whole building services’ approach to ICT services design, Tommy ensures that projects are provided with a bespoke, practical and integrated solution. Tommy is skilled in assisting our clients understand new possibilities, getting the most out of their investment in ICT, and ensuring that their technological objectives are exceeded.

Connan Brown | Senior Associate

  • Connan is a chartered sustainability and mechanical engineer who has been operating in the Australian, New Zealand and UK building services industries for 20+ years.

    Starting in mechanical design and multi-disciplinary project team leadership Connan’s keen interest in sustainability has developed over his working career. This deeper understanding of sustainability in design and operation supports optimisation of both design and long term building outcomes.

    His project experiences include commercial, health, education, defence, retail, residential, industrial, hospitality, sporting facilities, refurbishment, renewables and rating tools, amongst others.

Craig Ward | Senior Associate

  • Craig is a seasoned and Chartered Building Services Electrical Engineer with over 12 years in the building industry. He has served as Lead Electrical Engineer on numerous large-scale and complex projects and has held various internal company leadership positions. He is an experienced project leader with a track record of delivering large multi-disciplinary projects and has extensive engineering design experience across diverse markets sectors including new and existing commercial office towers, interior fit-outs, retail, residential towers and correctional facilities. 

    Craig has a broad technical skillset in addition to electrical engineering, including significant experience as a mechanical and hydraulics engineer. This combination of broad technical knowledge and client centric project management makes Craig a versatile and effective project leader.

John Holdich | Senior Associate

  • John is a Chartered Building Services Engineer, Chartered Project Manager and a WELL Accredited Professional.

    Specialising in hydraulic and mechanical services design, sustainability design and asset management, John has valuable extensive experience delivering landmark projects in Australia, the Middle East and the United Kingdom. He has particular expertise in the correctional, transport and industrial market sectors to compliment our Melbourne office.

Matt Meachem | Associate Technology Consultant

  • Matt is an Associate Technology Consultant with over fifteen years of experience shaping the future of the technology industry. As the leader of the NSW ICT pod, he specialises in transforming complex, technical challenges into modern, connected building solutions. His ability to drive future-focused solutions and manage end-to-end delivery provides significant project benefits.

    Matth is a WiredScore and SmartScore Accredited Professional, highlighting his expertise in delivering projects that are not just cutting-edge but truly future-proof. He brings deep passion to a broad range of subjects, including ICT networking, smart building integration, operational technology, audio visual technology, and unified communications.