Connell Brothers Ltd (CBL) were appointed by Jones Land LaSalle to carry out the internal strip out, part demolition and façade removal of the former BHS Stores in the Manchester Arndale Centre prior to the store undergoing a full refit. The store was surrounded by live retail stores on three sides and fronted by Market Street, a busy pedestrianised thoroughfare.

The scope of the works initially involved the removal of all asbestos-containing materials, all the soft finishes, mechanical and electrical equipment, water and waste services, heating and ventilation equipment, escalators and fire alarms. The existing lifts were retained and a new temporary fire alarm system and lighting installed. All materials were required to be removed to the basement level where they were placed in skips and removed via the underground loading area. The external façade was to remain untouched.

Welfare units were constructed within the basement area and the existing loading bay was utilised as a laydown area for skips to remove the waste material. The air conditioning system was removed in order to utilise the vertical shafts as drop chutes to remove material from the floors. Operatives then worked through the floors removing all the soft furnishings and segregating them into individual waste streams before removing them via the drop shafts. This maximised the amount of material that could be recycled. Access routes were formed through the floors using barrier tape to ensure the safe movement of operatives during these works. Once the furnishings had been removed the services could be removed and the floor stripped back to its structure.

Following the main strip out works the larger items of plant were removed, including seven escalators. These were initially stripped using hand tools and given a clean to remove as much as possible of the oil and grease that had accumulated over the years and reduce the risk of a fire.

A block and tackle suspended from a lifting beam was used and the escalators carefully cut using oxy/propping cutting equipment before being lowered to floor level where they could be further size reduced and removed from the building.

During these works, the client instructed Connell Brothers to demolish various sections of concrete flooring to the building to aid with the refurbishment and new construction works.

A series of structural investigations were undertaken by Mott Macdonald and Connell Brothers to determine the structure of the building and to develop a removal sequence. Sections of two floors were to be removed and prior to any works commencing temporary steelwork required installing. Due to the dimensions of the building and the requirements of the client, each piece of temporary steel required individual manufacturing.

In addition, a large steel goalpost structure was required at the basement level. Once installed, hydraulic flat jacks were placed on the top of the steel frame and filled with high strength grout to a specified pressure to support the floor above.

A specific sequence of demolition was developed to ensure each bay of floor removed was sufficiently supported by props to allow demolition by mini-excavator. Diamond wire cutting was used to separate beams from the retained structure during the demolition works. An additional complication was that these works were required to be undertaken outside of business hours to minimise the disruption to adjacent retail businesses.

A further developnet in the works also required the removal of the front facade to the pedestrianised road. Once again these works were undertaken out of normal business hours. Investigations into the fixing system for the panels allowed for limited pre-removal works to be carried out prior to removal.

Once the panels had been prepared timber Navi mats were delivered to the site and placed on the pavement to the front of the building to allow a mobile crane to be set up. The panels were then attached to the crane and the final cuts made to enable the panels to be lifted whole to ground level where they were laid flat prior to being lifted onto the back of waiting wagons for removal to Connell Brothers yard in Salford.

Once a number of panels had been removed the crane was derigged and the Navi mats removed before the entire area was swept clean and the fencing removed in readiness for the morning opening of the Arndale Centre retail units.

These removal works were carried out over a number of nights and once completed a scaffold screen was installed to the opening to provide protection to the public during the following refurbishment works.

This project presented a number of challenges, namely:

Very limited access to the work area
Live retail units and pedestrian areas to the perimeter of the site
Installation of temporary steelwork in confined and difficult access locations
Development of a highly specific demolition sequence to maintain building stability
A large amount of night work to minimise disruption

Careful planning and the development of a close working relationship with the structural engineers were critical in ensuring the project was carried out safely, on time and with minimum disruption to adjacent businesses and the public.