Jeff has been involved in the construction industry from a young age through the family business of building contractors. Jeff has developed exceptional experience in the industry from the beginning and aside from the family business has spent many years on large scale projects with large scale national and multi-national construction companies, such as Ascon Ltd. on various roads and bridge works and Sorensen Ltd. on large scale pipelines.

Jeff served as an engineering officer in the Irish Defence Forces and retired as captain when he decided to establish O’Mahony Consulting Engineers.