07/07/2026
McDonnell Piling Uses Screwsol® for Ireland’s Tallest Residential Building
In Cork, Ireland, McDonnell Piling is working on two major residential projects, including what will be the country’s tallest residential tower. The key innovation: the use of Screwsol® piles, which generate minimal excavated material and reduce the amount of concrete used! These projects demonstrate Soletanche Bachy’s ability to deploy innovative, high-performance, low-carbon solutions on local projects.
Two projects, one technical ambition
In Cork’s Docklands, McDonnell Piling is simultaneously contributing to two landmark urban developments:
- Railyard Apartments, featuring a 25-story tower set to become Ireland’s tallest residential building
- Marina Depot, a large-scale urban transformation program, with a first phase comprising 337 housing units spread across several buildings
Two projects with different characteristics but a common challenge: constructing high-performance foundations in constrained urban environments while minimizing environmental impact.

Screwsol®: A Differentiating Solution for Everyday Projects
For both projects, the teams opted for a hybrid solution combining CFA piles and Screwsol® piles, a technology developed by Soletanche Bachy.
The principle: forming a displacement pile by creating a helical thread filled with concrete, which improves load-bearing capacity while minimizing the removal of excavated material.
This approach offers several key advantages for urban construction sites:
- Very low (or even zero) volume of excavated material
- Reduced concrete volumes
- Fewer truck trips and less construction site congestion
Concrete and measurable benefits
The results achieved on both projects fully illustrate these benefits:
- Up to a 52% reduction in concrete at Marina Depot compared to a traditional solution
- At Railyard, 41.9% less concrete and 28% less steel used
Beyond the numbers, these gains directly translate into a reduced carbon footprint and improved overall construction site efficiency.
Expertise That Makes a Difference Right from the Design Phase
In both cases, the early involvement of McDonnell Piling and the Soletanche Bachy teams made it possible to optimize the solutions right from the design phase.
- At Marina Depot, soil analysis led to the decision to use Screwsol® rather than CFA alone
- At Railyard, several years of upstream collaboration, including testing, helped secure the final solution
