Case Study // Marcol House – Great Portland Estates

This interesting scheme involved the partial demolition of a corner plot on Regent Street. We were pleased to work alongside our clients engineering team to develop solutions to particular challenges posed by the scheme.

This six storey grade II listed façade was retained totalling 50 meters in length, together with corbelling and balcony features.

As a consequence of the retained demise, it was necessary to remain flexible in the façade retention solutions, with an external temporary works retention system being developed for part of the Regent Street façade, and an internal façade retention system which incorporated the permanent steelwork being developed, to retain the façade above All Bar One.

Significant engineering challenges uncovered during the execution of the project, influenced the way the façade was tied back to the existing steel frame. The presence of column lines, which followed the stepped façade whilst utilising existing floor beams as local transfer structures, conspired to make the transfer of loads from exisiting to temporary structures more complex.

  • The tower crane was used for the demolition. The base was designed by Swanton Consulting and involved specialist low head room piling equipment. Due to the constraints of space and existing foundations the crane is set off-centre to the base.
  • Swanton Consulting designed the façade retention scheme working closely with City of the Westminster infrastructure team. The scheme relies on a combination of internal and external framing and gravity foundations.
  • An isolated room on the first floor was also retained. This involved the design of dead shoring to keep this delicate structure in place. Sophisticated monitoring techniques were used during the load transfer process.