| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| APPLIED POST TENSIONING SOLUTIONS LIMITED | 06660640 | 30/07/2008 | Silver |
| ENSPAN LIMITED | 07634603 | 01/07/2015 | Silver |
| INTERSPAN EUROPE LIMITED | 07315670 | 01/04/2014 | Silver |
| POST TENSIONING SOLUTIONS LLP | OC367679 | 31/08/2011 | Dissolved |
| SLABTEC LIMITED | 13160543 | 27/01/2021 | One Red Flag |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| ALLIANCE DESIGN UK LTD | 05586079 | 15/11/2010 | 01/01/2012 | Silver |
| STEEL CITY DEVELOPMENTS LIMITED | 08072449 | 24/01/2014 | 06/01/2023 | Bronze |
| UK CERTIFICATION AUTHORITY FOR REINFORCING STEELS | 01762448 | 23/01/2012 | 30/04/2012 | Bronze |