Delivering a considered engineering approach at Manchester’s St Michael’s project
The St Michael’s project is a joint venture between Relentless & Salboy, fronted by Gary Neville and Simon Ismail respectively. Split into two phases, the project will be a mixed-use development comprising office, hotel and residential facilities.
St Michael’s will take its place as one of Manchester’s most distinctive skyscrapers and push the boundaries of high-quality hospitality, residential and office spaces in the UK’s second city.
As engineers for Phase 2 of the project, we’ll be bringing all of our engineering know-how to deliver the project efficiently. Our work includes the design of a three-storey basement, and a 42-storey, mixed-use tower.
An interesting build on three fronts
The daring city-centre design will involve its fair share of engineering challenges and there are three primary facets of this:
- The building height
- The extremely tight working site
- The three-storey basement structure.
The height of the building has required us to think about the requirements for human comfort coupled with building stability. The tight site has required us to think carefully about the construction schedule, site access and any knock-on effects to nearby Grade II listed buildings. Finally, the three-story basement has required a considered and pragmatic excavation and temporary works strategy to protect nearby buildings.
Approaching the challenge of a tight site
Working closely with Domis and Mayo Civils – the main contractor and ground works contractor – as well as the construction methodology has been absolutely key in overcoming the constraints of the site.
It’s for this reason that we considered the construction sequence in the earliest design stages. By factoring this into our design decisions, we’re able to put a robust process in place that will make the construction of the tower more streamlined and buildable.
Approaching the challenge of building height
Here at renaissance, we’re no strangers to engineering tall structures. Our recent work on Salboy’s Viadux and our previous work on the high rises at Anchorage stand us in good stead to tackle the 42-story tower of St Michael’s.
An important part of our work, particularly on high-rise structures, is our ability to rationalise the structural form of the building, prioritising simplicity and removing excess materials. This is an approach we’re applying to St Michael’s, delivering a considered design that’s carbon sensitive and therefore cost-effective.
The larger spans of the residential and hotel spaces have been driven by the architectural form and will be constructed using post-tension concrete slabs, reducing the weight of the structure. Also, to provide more open space in the reception areas, the stability outrigger walls are transferred onto mega columns, supporting the weight of the structure above.
Approaching the challenge of the three-storey basement
To ensure that the basement is excavated safely, we undertook a basement impact assessment across the whole site. Importantly, this allowed us to understand how this intervention will affect the surrounding buildings.
The safety of our neighbours is absolutely paramount during the construction of St Michael’s, especially given the historical significance of many of the surrounding heritage structures. This assessment is an important and necessary step in understanding how to safely excavate the ground to form the basement structure, install the required temporary works and deliver a high-quality solution replete with all of the amenity expected of a building of this calibre.
A truly exciting project
This Relentless and Salboy joint venture will be a real jewel in Manchester’s crown, delivering a modern building that accentuates the history of the area while adding a modern twist.
With the excavation of the 3-storey basement now complete, we have the first engineering challenge delivered on-site and we can’t wait to show you our progress on the project. Be sure to check back soon for an update.
