Morrisons Head Office

Planning permission was sought and gained for an additional, 356 space car deck on the western side of the office development over part of the existing parking area.

A number of planning restrictions were included by the local authority on the net gain, the aesthetics and they also required that the new deck should not be higher than the adjacent highway (Gain Lane). The existing contours of the site made this quite feasible due to the current level being some three metres lower than the highway. Morrisons themselves and the planners were both keen to harmonise the appearance of the proposed car deck with the existing building and the initial presumption was that a new deck would have to be a composite steel and concrete construction to achieve this.

Morrisons Project Manager Gareth Wilkinson looked at a number of possibilities together with architects Race Cottam Associates and cost consultants Rex Proctor & Partners. Their assessment also had to consider their level of confidence and assurance that the selected contractor could deliver what was required in today's challenging market. In that respect the backing of parent company Hill and Smith was an important factor in supporting TopDeck's credentials. Hill and Smith are a heavyweight in the steelwork and construction industry and have proven resources and expertise.

The TopDeck design considerations presented a weighty argument in favour of selection due to the modular, off site assembly and the future development possibilities offered. The complete deck, classified as an asset, can be relocated if required to one or multiple sites should the business needs change in years to come.

Once TopDeck were appointed, the custom design was developed further to meet Morrisons' very specific requirements. Particular attention was paid to the envelope of the structure. A natural sandstone cladding system was designed to fit at the perimeter of the deck to be used in conjunction with the Flexi-Panel safety barrier system from Berry Systems (a sister company of TopDeck Parking). The clean lines of the cladding, capping panels and the powered coated inertial barrier infill panels all combined to create a facade that would sit in perfect harmony with the existing office building.

Additionally the structural support columns and bracing panels were designed to be encased with a brushed stainless steel effect to mirror the supporting columns on the periphery of the office. This ensured that all aspects of the planning requirements were met as well as Morrisons own preconditions.

TopDeck's success has been driven by its philosophy of modular construction and off site assembly. Pre-applied surfacing reduces programmed risks and introduces the key benefits of a controlled environment. This further increases the overall level of quality. The pre-assembled modules are dispatched to arrive on site on a daily basis in accordance with a construction programme that is kept flexible to maintain and meet the clients changing requirements.

At Morrisons the maximum use of the existing parking level was maintained during the installation of foundations, civils, steel erecting, lighting, drainage, cladding and CCTV. While some areas had to be closed for just a few days at a time this was soon balanced by bringing parts of the new deck into beneficial use at a very early stage. Finishing works were carried out in phased, localised areas further reducing the occupation of the site's parking space capacity.

Access to the new deck is via a ramp on the South west corner of the site. The existing contours of the land in that area facilitated the construction of a ramp using more traditional methods. Built into the embankment with retaining walls and a concrete slab, compliance with the IstructE design guidelines was carefully checked as well as measures to ensure it did not compromise the adjacent highway. The retaining walls were finished in sandstone block work and coping stones matched to the perimeter cladding. Other features and materials used in relation to the elevations were carefully selected to give a quality and well proportioned design.

The installation of the ramp was run independently to the car deck but was still on the critical path of the whole project because of the extended construction time of the more traditional methods used.

Framework construction started during the second week of December 2011 and despite a site closure during the Christmas holiday, the deck was fully constructed in a period of 6 weeks. Beneficial use of the new deck was given to Morrisons, on time, during the first week of February 2012. Additional finishing works were continued in smaller construction pockets at the perimeter of the deck and completion made shortly afterwards.

Download the casestudy (PDF)