• The project had demanding site conditions, including the discovery of underground wells,
basements, oil and asbestos.
• The development had a challenging, innovative design that included a kinetic wall, the fi rst of its
kind in the West Country.
• The client required achievement of BREEAM Excellent.
How these were delivered
• Prior to commencement of works, Midas reviewed all Ordnance Survey maps of the area and
commissioned a ground penetrating radar scan of the site for unexploded ordnance, as Devonport
Dockyard was heavily targeted for bombing during World War Two. During excavation works the
team discovered several voids including basements, bank vaults and foundations of buildings
destroyed during the Blitz. Midas pumped 400 tonnes of Type 1 granular fill compactable material
into the holes, solid enough for the 55-tonne crane to sit on, and filled other excavations with
concrete. The site fenced off excavations, with a vehicle controller in place to guide operations of
plant and excavation machinery, and tested the ground for stability before each stage of the works.
The team completed excavations under close, careful management, utilising remote compactors
over the arches and basements to avoid risk to operators.
• Midas joined this design and build project at RIBA Stage 2. The innovative design included use of
a kinetic wall to reflect light and move with the wind, and random rubble stone cladding to some
elevations. Midas constructed the kinetic wall, which is nearly six metres wide and over seven
metres high, with 1,786 aluminium shingles affixed to steel wires attached to a full-height screen
over the main entrance. It is the first of its kind in the west country and provides a distinctive feature
of the development. Midas completed and connected the gable ends of the buildings early in the
project, adjusting the programme to mitigate this requirement and completing the gable ends
as soon as possible to make the buildings watertight and enable progression of interior works.
Internally, the structural grid and division walls were designed to be easily combined to provide
larger floor plates to respond to market interest.
• Midas successfully achieved BREEAM Excellent through provision of bicycle storage; attaining a
lower Building Emission Rate than the Target Emission Rate; and installation of one bat box, one
bird box and one bee brick on each building. Midas fitted a PV array to the roof of the office, with
an estimated annual generation of 19,616.00kWh and a declared net capacity of 20.00kWh. The
team also planted verges and trees, improving the site’s ecology, and achieved a 98% recycling
figure, with demolition waste sent for reprocessing and reuse.
• Midas liaised with the neighbouring Ministry of Defence (MOD) site in advance of
commencing works to coordinate logistics and ensure the site kept MOD access clear at all
times. The site employed several gate controllers and traffic managers to ensure safe site
access, with radio-linked site management teams.
• The site contained multiple underground services, including a gas governor and electrical
transformer. During excavation works the site team uncovered more than 130 services, not
included on any plans or surveys, including underground external drainage. The team hand
dug excavations to expose cables and arranged for the isolation of services, with utilities
proved dead before works proceeded. Midas included a service grid system over the site
survey, overlaid on a plan of the new buildings.
• The project had restricted site access that presented challenging logistics, which had a
significant impact on the construction programme. Midas mitigated this by utilising weekend
working and employing a high volume of staff, including increasing the number of managers