John Gannon Concrete Ltd The business goes back to the early 40's at which time Joe Gannon - father of John Gannon - was extracting material and manufactured concrete products from the early 50's. The company has since expanded, diversified and developed over the years to serve the many changing needs of our customers in the construction industry. Today Gannon Concrete supplies an extensive range of: Eco concrete products Thermal Concrete Blocks Concrete Blocks Bagged aggregates Octoblocks Road barriers We have built a strong client base in many sectors including construction, farming, housing, civil engineering and local authorities.