About O.P. Industries Group

The O.P. Industries Group is an Australian-owned mechanical and HVAC group of companies delivering end-to-end building services solutions across commercial, industrial and government sectors.

With more than 50 years of experience, we have built a reputation for reliable delivery, technical capability and consistent performance on complex mechanical projects — particularly within live, operational and highly regulated environments.

  • Founded in Wangaratta, O.P. Industries was established by Lou Onley and Graeme Plumridge, initially servicing regional Victoria and New South Wales. From these beginnings, the business developed strong expertise in mechanical services, process pipework and stainless steel fabrication, delivering major regional infrastructure projects including Wangaratta Base Hospital and defence-related industrial facilities in Benalla.

    In 1993, the company expanded into Melbourne, establishing a metropolitan operation that has since grown into one of Victoria’s leading mechanical services contractors. Today, O.P. Industries operates across metropolitan and regional Australia, maintaining strong ties between city and regional teams to deliver projects efficiently and consistently at scale

  • Safety
    We prioritise the safety of our people, clients and sites through disciplined systems and a strong safety culture.

    Technical Excellence
    We deliver engineered solutions that perform as intended, from design through to commissioning and operation.

    Accountability
    We take ownership of our work, communicate clearly and stand behind the outcomes we deliver.

    Collaboration
    We work closely with clients, builders and consultants to deliver practical, coordinated solutions.

    Performance & Improvement
    We continually review, optimise and improve how we deliver to achieve better outcomes and long-term value.

    Sustainability
    We focus on efficient, resilient building services that support energy performance and asset longevity.

  • Regional Victoria & Southern NSW
    Our origins in Wangaratta underpin a long history of delivering mechanical services across regional Victoria and southern New South Wales. This includes healthcare, industrial processing, logistics and regional infrastructure projects, supported by in-house fabrication and strong local capability.

    Melbourne & Metropolitan Victoria
    From our Melbourne operations, we have delivered complex mechanical services across healthcare, pharmaceutical, commercial, industrial and data-critical facilities. Our metropolitan work is often delivered within live environments, requiring close coordination, staged delivery and rigorous commissioning.

    South Australia
    Since establishing operations in Adelaide in 2008, O.P. Industries has delivered technically demanding projects across defence, public infrastructure and specialist healthcare and research facilities. These projects have strengthened our capability in secure, regulated and high-performance environments.

    Tasmania
    More recently, O.P. Industries has expanded into Tasmania, delivering advanced education and scientific facilities. These projects reflect a growing focus on sustainability, energy performance and fully electrified building services, and represent some of the most innovative work we have delivered to date.

    Together, this national footprint allows O.P. Industries to combine local delivery capability with metropolitan scale and technical depth.

  • Across our regional and metropolitan operations, O.P. Industries has delivered mechanical services for some of Australia’s most technically complex and high-performance facilities.

    Our experience includes:

    • Defence and secure infrastructure, including works for RAAF Base Edinburgh and specialist defence research facilities, requiring robust, resilient and highly controlled mechanical systems

    • Data centres and mission-critical facilities, delivering high-availability cooling, redundancy and environmental control for telecommunications and secure data environments in Melbourne

    • Advanced healthcare and research facilities, including involvement in Adelaide’s Australian Bragg Centre for Proton Therapy, one of the most sophisticated medical and research facilities in the Southern Hemisphere

    • Sustainability-led education and scientific buildings, such as the University of Tasmania’s Forest Building redevelopment, incorporating fully electrified heating and cooling, high-efficiency systems and a strong focus on long-term building performance

    These projects demonstrate our ability to deliver mechanical services in live, regulated and high-risk environments, where system performance, commissioning discipline and lifecycle outcomes are critical to success.

  • O.P. Industries is led by an experienced management and technical team with deep expertise across mechanical engineering, project delivery, commissioning and asset services.

    Our people operate across metropolitan and regional Australia, working collaboratively to deliver safe, reliable and high-performing mechanical systems. We invest in long-term capability, technical development and leadership continuity to support our clients and our projects.

    Executive / Leadership

    • Managing Director- Earl Sakareassen

    • Director / Group General Manager- Brendan Dozzi

    • Group Chief Financial Officer- Sharon Giggins

    • General Manager- Wangaratta- Mark Wright

    • State Manager- South Australia- Matt Noble

    Technical / Delivery Leadership

    • Construction Manager- Victoria And Tasmania Darren McGrath

    • Engineering Manager- Chris Oresti

    • Commissioning Manager - Paul Dozzi

    • Service / Warranty Manager- Victoria and Tasmania - Chris Morrison

    • Service / Warranty Manager- Adelaide- Brad McKay

    • Estimating Manager- Ray Hilyear

    • NEBB Certified Professional- Keith Pearson

multi-state Coverage

We proudly service Melbourne, Adelaide, Tasmania, Regional Victoria and NSW, providing responsive local support backed by multi-state capability.

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MembershipS & certifications

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ISO 9001 Certified Quality Assurance logo
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ARC logo with stylized letters and a checkmark design, accompanied by text indicating ARC authorization number AU-17993.