16th April 2020

Sentinel Building, Glasgow

Working with Michael Laird Architects, Doig and Smith (Project Manager and Quantity Surveyors) and main contractor Thomas Johnston, we acted as Structural Engineers on the redevelopment and extension of one of the most distinctive buildings in Glasgow, the Sentinel Building.

The project , for Ardstone Capital, began in November 2018 and comprised the proposed extension and refurbishment of the 84,104 sq ft, 9-storey commercial office building in Glasgow City Centre.  The project began with an initial feasibility assessment as one of the key challenges was to develop proposal options that could be constructed incrementally; some of the building’s tenants continued to operate in the building during the construction and renovation period.

Our role continued throughout each stage of the project and we had to carry out different roles at different stages.  During the feasibility stage, a new panoramic steel framed extension to the roof was designed as an option, and the core lift shafts were reconfigured and extended to accommodate the additional floor plate and improve the vertical transportation logistics. Strengthening works were also needed to the existing structural columns to bear the extra load of this extension.

The existing steel frame was modelled in Revit by our team and this model was used by the design team as their base model throughout the design development and detailed design. Finalised alteration options included strengthening of columns on non-occupied floors in anticipation for an extension at some point in the future, new high-speed lifts and an increased reception area with a bespoke floating feature window seat supported from a newly installed cranked concrete slab.

During construction, we were appointed to complete the temporary works design required to accommodate the strip out of existing floor plates and basement alterations. This involved temporary propping of existing composite floor slabs adjacent to newly formed penetrations and support to a historic masonry retaining wall within the basement.

As an add on to the original design scope, we reviewed the ongoing works being carried out to replace the external stone cladding. The original cladding panels covering the whole building were found to be in poor condition, requiring complete replacement. We reviewed the relevant sub-contractor’s packages and worked closely with various stakeholders to develop a workable solution.  This extensive collaboration with the design team, contractor and subcontractor required meticulous attention to detail and we needed to ensure that any issues were both discovered and corrected.  The close working relationships we developed with the subcontractor design team and specialist supplier’s technical groups were particularly valuable in ensuring that the best solutions were delivered on time and innovative structural solutions were implemented. 

The restoration and extension of the Sentinel Building has provided our Glasgow team with many interesting structural challenges, opportunities to demonstrate the breadth of our skills and also illustrate the importance and benefits of true collaborative working for a design team.

Sentinel Building, Glasgow