The existing Supper Room annex to the Mansion House had been in use as a Restaurant for the previous ten years. CORA were asked to look at the feasibility of converting the lower ground floor area which was currently used as sub-standard offices and storage into Restaurant space by removing large structural columns and beams and replacing them with much smaller structures, while underpinning the walls and dropping the foundation levels.
Emphasis was placed upon the phasing, the methodology and sequencing of the works due to the necessity to keep the upper level of the building open for business for the majority of the works.
Dialogue was required regarding the temporary fire exit routes that had to be maintained during construction and this had to be incorporated into our design strategy.
Extensive consultation and investigations were undertaken with the ESB and utility providers to determine the existing services in the knowledge that this building once housed the first central Electricity substation for the old corporation for the city. The works were undertaken around 12no High voltage cables that were isolated but maintained live for the duration of the works.
Specific site method statements had to be produced for the demolition phase of the works taking into consideration the fragile nature of the glazing of the protected structure over, the noise and dust requirements not to affect the customers of the restaurant and the hygiene aspects regarding a working kitchen in the vicinity.
The works included a new private dining area with a glazed roof light connecting the existing structure to the new which is 65m2 and is supported intermediately by glass sandwich flitch beams.