Guestwick AGI (G35 Appraisal)

Providing design, structural assessment, G17, G35 and P55 approval and appraisal services, and specialist structural inspections, to the energy industry

The challenge

Guestwick Above Ground Installation (AGI) is one of the Feeder 2 block valve sites which form a key part of the UK Gas National Transmission System (NTS), which transfers gas from Bacton Gas Terminal. Due to its ageing infrastructure, Guestwick AGI was included as part of the National Grid’s ‘National AGI Renovation Campaign’, which commenced in January 2018.


Appraisal works

Inertia Consulting Ltd was appointed to appraise the civil and structural works relating to the replacement of the old block valves and corresponding gas infrastructure, security fencing, road layout and drainage systems. Our G35 Appraisal was undertaken in line with the latest Gas Standards and National Grid Specifications.

The project team
  • National Grid Gas plc – Client
  • Murphy & Sons Limited – Main Contractor
  • Premtech Ltd – Designer & G35 Approver
  • Inertia Consulting Ltd – G35 Appraiser