A Fast Fix for a Landslip: Northern Ireland's A2 Road Rebuilt with Redi-Rock XL

The Challenge: Reopening a Vital Coastal Road

Northern Ireland’s A2 is a highlight of the renowned Causeway Coastal Route, a world-famous scenic drive that winds along the Antrim coast through dramatic landscapes, seaside villages, and the Glens of Antrim. When heavy storms created a landslip that washed away a portion of the A2’s Chapel Road section in Cushendall, the resulting closure disrupted a major tourist thoroughfare, cut off direct access between communities, and forced drivers, including large tour coaches, onto narrow country roads. Restoring the road was critical not only for local residents but also for keeping visitors moving along one of Northern Ireland’s signature travel experiences.

Major transportation contractor Highway Barrier Solutions (HBS) partnered with Ballymena, County Antrim-based Redi-Rock producer Moore Concrete to find a long-term roadway restoration solution. The circumstances demanded a retaining wall that could be installed within a small footprint, require no reinforcement, and support massive traffic loads, including large coaches. The solution would also need to be installed quickly, since the road had already been closed for over a month.

Why Redi-Rock? Faster Installation. Less Excavation.

HBS selected Redi-Rock’s XL Hollow-Core blocks for the A2/Chapel Road repair. The XL Hollow-Core provided the structural capacity and installation speed needed to help restore the road to service. Designed for large-scale retaining wall applications, these oversized precast concrete blocks feature a hollow design that increases the efficiency of both transport and installation. Once the block is set, a cavity in the the XL Hollow-Core block can be filled with aggregate or concrete. Some project-specific designs may even incorporate rebar or additional reinforcement, depending on engineering requirements, loading conditions, or local regulations. The XL Hollow-Core system can build gravity retaining walls up to 8 m (26 ft) high without geogrid reinforcement, making it ideal for a project like A2/Chapel Road, where the surrounding geography limited excavation space.

Additionally, each XL Hollow-Core block offers more than 1 sq m (11.5 sq ft) of face area, allowing for the installation of more block face with fewer picks. HBS completed the retaining wall in approximately one week, estimating that they installed the Redi-Rock XL Hollow-Core wall 3.5 times faster than if they had selected a smaller block alternative. That installation speed was especially important for a road that had already been closed for multiple weeks.

The Redi-Rock XL Hollow-Core system delivered several key advantages for the A2/Chapel Road project, including:

• Rapid installation. Installed in a one week, the retaining wall required only a fraction of the time estimated to install alternative small block solutions.
• Limited excavation. The gravity wall solution avoided the need for additional geogrid reinforcement behind the wall, a necessity for a project with challenging topography.
• Road support. Redi-Rock’s patented knob and groove interlocking system resists soil pressure for greater wall stability, providing the structural support needed for heavy traffic volume and large vehicles like motor coaches.
• Faster reopening. Efficient installation meant that resurfacing preparations could begin within 10 days of the start of block installation.
• Government endorsed. The British Board of Agrément (BBA) awarded Redi-Rock’s XL Hollow-Core blocks Highway Authorities Product Approval Scheme (HAPAS) certification in 2022 and this project was approved by Northern Ireland’s Department for Infrastructure (DfI).

For Moore Concrete and Highway Barrier Solutions, the A2/Chapel Road project highlighted the value of matching a retaining wall system to a site's physical constraints, live load demands, and urgent timeline.

“Redi-Rock is not just a system, it's a solution.” –Michael Esler, Moore Concrete

Redi-Rock XL Hollow-Core isn’t just for transportation applications. From lakefront homes to zoos and everything in between, engineers and contractors trust XL Hollow-Core to build big with efficiency and confidence. Explore more Redi-Rock XL Hollow-Core projects:

• Great Lakes Hybrid Wall Saves Home from Rising Water Levels
• Wisconsin DOT Uses Redi-Rock to Create Space for Pedestrian Path Near Large-Scale Highway Project
• Skyland Ranch Amusement Park Chooses Redi-Rock Gravity Wall to Replace Failing Boulder Wall
• More Room to Roam with Redi-Rock at Zoo’s Elephant Exhibit

Whether you're creating usable space, protecting valuable property, or tackling a challenging site, XL Hollow-Core delivers the versatility to bring ambitious projects to life. Price your XL Hollow-Core wall concept today.