Met Consultancy Group (Met) were contracted to provide a full measured building survey of this Victorian Grade II listed Triangle Builidng complex between the Cathedral and Manchester’s Arndale Centre. The current building was built in 1897 and refurbished in 1996 as a central pedestrian core with a magnificent glass roof and central glass dome. The current shop units wrap around this core in the unusual triangular shape with three main trading floors and a basement.
Liaising closely with the clients architects, Met’s brief was to provide a topographical survey around the building. This included floor plans at each level, a roof plan adhering to strict Health and Safety guidelines, external elevations and a full internal and external drainage survey with a CCTV inspection. The survey was to be carried out in the run up to Christmas when the centre of Manchester was very busy. Met worked closely with the centre to schedule survey works outside the peak shopping times and to avoid any disruption to a Christmas Market based outside the complex.
A fully connected control network was established in and outside of the building to account for its shape and ensure total accuracy of all survey elements. Internal floor plans and elevations were surveyed using total stations (connected with MBS software on hand held computers) and laser Disto devices.
Internally, the warren of rooms on each level made it necessary to use total stations to ensure room shapes were accurately recorded. Externally, the decorative facades were captured using the total stations in laser mode which when used with MBS, provides a quicker turnaround of completed drawings.
Surveying the roof was complex and large parts were inaccessible because of the amount that is glazed. It was possible to extend the control network on to the roof to provide a framework for the survey. Roof walkways provided an access around the top of the building and much of the detail was captured remotely via laser technology ensuring that works were carried out safely. Surveyors were harnessed to roof anchors when working on the roof unless another safe working practice was possible.
Working within a busy shopping centre during the Christmas period was also challenging for the teams carrying out the drainage survey. Much of the work was carried out at night, and access needed to be coordinated between several stores at the same time as much of the drainage was shared between different units.
Drainage connectivity was proven using electronic sondes inserted into the pipes and traced from the surface through dye testing and acoustic methods. Routes were also surveyed using CCTV to identify any incoming connections and provide a report on the condition of the system. Larger mainline CCTV systems were used to survey the public sewers outside The Triangle building, with access permits obtained from United Utilities.
The Triangle was a very interesting and challenging project that Met is pleased to have contributed to.