COSTAIN GROUP PLC

("Costain" or the "Company")

Board Notification - External Directorship

Costain has been informed that, with effect from 27 July 2015, Jane Ann Lodge, a Non-Executive Director of the Company, Chair of Costain's Audit Committee and member of the Company's Remuneration and Nomination Committees, has been appointed as a Non-Executive Director of Sirius Minerals Plc, an AIM listed company on the London Stock Exchange. Jane has also been appointed as Chair of the Audit Committee of Sirius Minerals Plc and will be a member of their Remuneration Committee.

This announcement is made in accordance with Listing Rule 9.6.14.

                                                                                                                          28 July 2015

Enquiries:

Costain Group PLC                                                                                     Tel: 01628 842444
Tracey Wood, Company Secretary