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Corrig House, Corrig Road, Sandyford, Dublin 18

+353 (0)1 295 2321

Suite D, Penrose House, Penrose Quay, Cork

+353 (0)21 450 2522

Company Profile


Company Profile

T.J. O'Connor & Associates is a consulting engineering firm, established in 1937. The company is an independent professional organisation providing clients with unbiased judgement and advice on specific projects, recommending the optimum economic and technical solutions.

T. J. O’Connor & Associates have acted as lead consultant in major Joint Ventures with Scott Wilson (now AECOM), the Dutch engineering consultancy firm the DHV group (now Royal HaskoningDHV) and DeVilliers (now Bigen Africa). From these joint ventures the company has availed of their partner’s expertise, large staff resources and worldwide experience.


T. J. O’Connor and Associates are delighted to have taken part in the NSAI BIM pilot project and subsequent achievement of NSAI certification to the International BIM Standard I.S. EN ISO 19650-2. Achieving this certification is a prestigious recognition of our efforts in integrating collaborative BIM processes and digital technologies into our company Quality Management System. This process is critical in adding value to our Client service, enabling us to achieve the very best in International Standards of information and collaborative project management procedures, both internally and across project teams, delivering the highest quality and best value for our Clients.  

T. J. O’Connor & Associates have developed their internal procedures in line with the Internationl BIM Standards ISO19650-1 and ISO19650-2, the associated British Standard National Annex in BS EN ISO19650-2 and associated documentation including Exchange Information Requirements (EIR) and BIM Execution Plans (BEP).

Our peronnel have experience in the development of BIM Protocols, including referencing the CIC BIM Protocol, and developing specifications for 3D Point Cloud Surveying works and subsequent BIM modelling works.

It is company protocol to develop our civil and structural engineering design and subsequent outputs utilising digitial technologies including Tekla Structures, Microdrainage WinDes and the Autodesk suite of products including RevitNavisworks, Infraworks and Autocad Civils 3D, with personnel experienced in analysing and developing BIM models using BIM related software solutions.

The firm has developed Project BIM models for a number of projects including the Radiation Oncology Centres for Cork and Galway Hospitals, Office Blocks at the Citywest campus and refurbishment and upgrading works to an existing industrial use building in Shannon for a South African based company.

The firm has an appointed BIM Manager and a number of BIM support staff, with senior staff having completed Masters in Construction Informatics, Post Graduate Certificate in BIM Technologies and Post-Graduate Diploma in Collaborative BIM


Since its foundation in 1937, T. J. O’Connor & Associates has been the lead designer in Civil Engineering of many of the country’s major wastewater systems, water supply projects and flood alleviation and management schemes.

We are adept at working in challenging environments including environmentally sensitive, Natura 2000 sites and marine and harbour works.

T. J. O'Connor & Associates developed for the Department of the Environment and Local Government the three Guidance Documents that form the basis of all public procurement of Small Water Services Schemes for DBO, Water and Wastewater projects.

The firm also prepped a guidance document for the preparation of Strategic Water Plans to be used by individual counties.

Members of our staff have been actively involved in redrafting the traditional forms of contract for the water industry and have represented the Association of Consulting Engineers of Ireland in consultations prior to the launch of the current suite of procurement documents for the Department of Finance.

Our clients include both public and private sector organisations and we have successfully completed numerous Design/Build (DB) contracts.

We were employed as Client’s Representative on the first Design/Build contract undertaken in this country at Osberstown Waste Water Treatment Plant in Co. Kildare. The tender documentation developed for this project has been widely used on most subsequent DB/DBO contracts throughout the country.

The firm were involved in the first Design/Build/Operate (DBO) contract to be undertaken in the State in Co. Monaghan which comprised the ‘bundling’ of a number of group and public water treatment schemes under a single DBO contract.

Our firm pioneered the use of Dissolved Air Flotation Treatment Plants and designed the first mesophilic (heated) anaerobic sewage sludge digestion plant in the State at Tullamore in 1986.

T. J. O'Connor & Associates prepared an inventory of water schemes in Co. Donegal in the mid 1990's and installed comprehensive water Management Information System (MIS).

We have acted as Employer’s Representative and PSDP (previously PSDS) on a range of public works contracts for a variety of local authorities across the country.

We have undertaken the Masterplanning and Infrastructure design for a range of large business parks and are leading the way in the design of innovative Sustainable Urban Drainage Systems (SUDS), including the completion of SuDS Strategy Reports for a number of developments around the country.


T. J. O’Connor & Associates deliver Structural Engineering Design Services on a range of major projects including shopping centres, office and commercial developments, hotel and leisure complexes, healthcare, education, residential and industrial buildings.

Our design services incorporate innovative structural solutions and have included the world’s first bi-steel lift cores, constructed as part of the Dundrum Town Centre development.

We have extensive experience in the design of renovations and refurbishments to existing buildings, including protected historical structures.

Our design staff are skilled at working closely with all members of the design team and liaising with organisations to achieve the Client’s vision on time and within budget.

The quality of the structural design work carried out by T. J. O’Connor & Associates has been recognised through the firm receiving both the Excellence Award for Structural Design and the Innovation Award of the Association of Consulting Engineers of Ireland