John Barker commenced his career being articled to a long established firm of architects, where amongst other work he had an introduction to and involvement with historic country houses.  In his second employment he joined another architects practice which had been founded and had enjoyed a consistent involvement with church work since the 1870s.  It is here that he had the opportunity to specialise in work on churches at a relatively young age and attended a course at the Institute of Advanced Architectural Studies in York. 

He progressed to partnership status and continued in this role for eighteen years. During the past sixteen years he has been director of his own company which has dealt exclusively with ecclesiastical work involving quinquennial inspections and subsequent repair and conservation projects together with re-ordering schemes. He has now had experience with working on over 160 churches and chapels. 

During his career he has been the surveyor to a project, at Radstone church Northamptonshire, which won the John Betjeman Memorial Award (National) for exemplary repairs to churches. He is also a past winner of the King of Prussia’s Gold Medal Award (National) for greatest aesthetic/technical challenge, in a scheme at Lowick church, Northamptonshire. His work at Wardley church, Rutland was commended in the George Phillips Awards (administered by Rutland County Council) for a project which made a significant contribution to the local built environment and highly commended in the Natural Stone Awards (National) by the Stone Federation Great Britain (Repair and Restoration category) for works at Crick church, Northamptonshire.

He is on the approved list of architects and surveyors for carrying out quinquennial inspections in the dioceses of Peterborough and St Albans and is also a member of the Peterborough Diocesan Advisory Committee for the Care of Churches.

He has been a consultant surveyor to The Churches Conservation Trust dealing with redundant churches in various counties.

He is a Trustee and Vice Chairman of the Northamptonshire Historic Churches Trust and a Trustee of the Francis Coales Charitable Foundation which also grant aids repairs and conservation work to churches.

John is a Member of the Royal Institution of Chartered Surveyors and is an RICS Certified Historic Buildings Professional (conservation accredited). He is also a Fellow of the Chartered Institute of Building, a Fellow of the Royal Society of Arts and a Member of the Institute of Historic Building Conservation.

Memberships also include the Ecclesiastical Architects and Surveyors Association, the Society for the Protection of Ancient Buildings and the Ecclesiological Society.