M27 junction 12 Hilsea Interchange IBM bridge repairs

Latest updates

• 13 August 2025

  Overnight and weekend closures

  Overnight closures (9pm-6am)

  Westbound M27 closed at Portsbridge roundabout

  • Monday 18 to Thursday 21 August
  • Monday 29 September to Friday 3 October

  Eastbound M27 closed at junction 12

  Monday 3 to Friday 7 November

  Full weekend closures

  Westbound M27 closed at Portsbridge roundabout:

  • 9pm Friday 5 to 6am Monday 8 September
  • 9pm Friday 26 to 6am Monday 29 September

  Westbound M27 diversion:

  • leave M27 at Portsbridge Roundabout
  • take second exit onto the A27 Western Road
  • turn left at traffic lights onto Southampton Road to rejoin the M27 westbound

  Diversion to join M275 southbound

  • leave M27 at Portsbridge Roundabout
  • take second exit onto the A27 Western Road
  • turn left at traffic lights onto Southampton Road to join the M275 southbound

  Eastbound M27 closed at junction 12

  • 9pm Friday 10 to 6am Monday 13 October
  • 9pm Friday 17 to 6am Monday 20 October

  Eastbound M27/A27 diversion:

  • leave the M27 at J12
  • turn right at traffic lights onto A27 Western Road
  • take second exit at Portsbridge roundabout to rejoin the A27 eastbound

  Alternatively:

  • follow the M275 southbound towards Portsmouth
  • leave the M275 at the Tipner interchange
  • take the 3rd exit to rejoin the M275 northbound
  • bear left toward A27
  • turn right at traffic lights onto A27 Western Road
  • take the second exit at Portsbridge roundabout to rejoin the A27 eastbound

  Northbound M275 diversion to join the M27/A27 eastbound:

  • leave M275 at junction 12 towards A27
  • bear left toward A27
  • turn right at traffic lights onto A27 Western Road
  • take second exit at Portsbridge roundabout to rejoin the A27 eastbound

  Please remember that closures can change at short notice. Sometimes unforeseen circumstances mean we can't work to programme. We’ll update these details if we need more time to finish our work.

  You can check the latest information on our daily closures page or find live travel information on our Traffic England site. Our travel alerts give details of live incidents on our network.

• 18 July 2025

  First phase complete

  We've now completed the first phase of our works ahead of programme. The lane closures have been removed, while other works not requiring lane closures, continue underneath. 

  Our next phase of closures are:

  • Eastbound: Monday 4 August – Thursday 7 August. 9pm – 6am nightly
  • Westbound: Monday 18 August – Thursday 21 August. 9pm – 6am nightly

• 15 July 2025

  Overnight closures planned for August

  We're still working overnight until Monday 4 August (lane closures).

  From Monday 18 to 27 August (9pm-6am) we'll have overnight weeknight closures.

• 15 May 2025

  Essential work starts soon

  Essential repairs start soon on two bridges near the M27 Junction 12 Hilsea Interchange in Hampshire.

  Known locally as the IBM bridges, one carries the M27 carriageway eastbound and the other westbound, near the Portsbridge Roundabout.

  The work will include replacing both bridges’ expansion joints: these allow for the expansion / contraction of bridge decks, caused by temperature variations and traffic movement. 

  We'll also:

  • replace kerb drainage and upgrade the drainage systems
  • re-waterproof and resurface the bridge decks
  • repair concrete underneath both bridges 

  For safety, we need lane closures throughout June, July and early August. There'll be

  • a 24/7 lane closure of the M275 northbound to where it joins the M27 eastbound, starting 22 June and continuing for three weeks
  • lane closures from 8pm Thursday night through to 6am Monday morning on the M27 westbound

  We'll also need some overnight, full carriageway closures in August. We'll do this in one direction at a time to limit disruption to traffic as much as possible. 

  In September to the end of November, we'll need some full weekend closures. We'll do this in one direction at a time to limit disruption to traffic as much as possible. We'll update this web page with full dates/details once they're confirmed.