Having undertaken a value engineering exercise on the station designs in partnership with architects WilkinsonEyre and SME Expedition Engineering, it was concluded that structural thicknesses and profiles in the roof could be modified to allow for less material.
The team said a total steel reduction of over 1,000t is possible, which represents a significant reduction in embodied carbon and a cost saving of £7M.
WSP Project Director Adrian Tooth said: “Taking the benefits from wind tunnel testing and snow modelling, we have been able to make small incremental changes and reductions in material thicknesses of the roof resulting in a significant saving in the cost of the station.”
HS2 Programme Director Matthew Botelle said: “By challenging the standard design approach, the team have realised savings in the roof steelwork tonnage that has significantly reduced cost, construction complexity and embodied carbon.
“This work is a great example of how the latest design thinking and techniques are being used on the HS2 programme to provide best value to the UK taxpayer.”
The roof at Old Oak Common comprises a series of tapered vaults with glazed rooflights to provide ventilation and daylight for the station.
Spanning up to 65m, the vaults are formed from fabricated steel box section arches and are supported on box section primary beams founded on tapered steel columns.
Fabricated using weathering steel, the visible parts of the roof steelwork will be painted for aesthetic reasons.