by MacAlpine


Interspan sustainability

Post-tensioning and reducing carbon emissions

Nestled in the Wallasey, Merseyside, the Millers Quay (also known as Wirral Waters Legacy Residential), development redefines modern living and paves the way for a sustainable future.
With the slab thicknesses reduced using post-tensioning (PT) in place of standard reinforced concrete slabs, this project stands as a shining example of innovation in the UK’s residential sector, particularly when it comes to reducing carbon emissions.

Midwest Formwork (UK), a leader in reinforced concrete frames & and groundworks, engaged Interspan, a leader in designing and constructing post-tensioned slabs. This collaboration generated material savings on the project and also significantly reduced the project’s carbon footprint.

Interspan’s approach converted the 275mm thick reinforced concrete slabs to 250mm thick post-tensioned slabs. This strategic choice resulted in savings in reinforcement tonnes and concrete volume, leading to an impressive reduction in upfront carbon dioxide (CO2) emissions.

The numbers speak volumes:

The total reduction in CO2 emissions across the expansive 37,375m2 scope of the project equated to an astounding 1,250T.

To put this into perspective, this is equivalent to the carbon emissions from more than 1,450 flights between London and New York or the CO2 output of over 400 average family cars over an entire year.

Miller Quays isn’t just reducing carbon emissions on paper—it’s actively contributing to a greener future.

The commitment to sustainability extends beyond the immediate project timeline. The integration of post-tensioned floor slabs not only cuts down on carbon emissions during construction but also underscores the development’s long-term impact.

During construction, detailed coordination was required to ensure that PT anchors were cast into the beams at the correct locations, along with the other cast-in fixings for the facade.

The fast cycle times associated with PT slabs by striking falsework after final stress, combined with this clever use of precasting, gave substantial efficiencies in the construction programme.

Millers Quay isn’t just a residential development—it’s a beacon of progress. The reduction in carbon emissions achieved through Interspan’s innovative post-tensioned slabs showcases what can be achieved when industry leaders prioritize sustainability.
As the project approaches completion in 2024, the community eagerly anticipates the arrival of a living testament to responsible construction and a more sustainable future.