According to information specialist Glenigan, Kier secured around 26 jobs worth more than £500m during the month.
These wins included a £200m residential scheme at Hardingstone for Homes England, a £50m office project in Durham for the county council and a £40m medical research project in London for the London School of Hygiene & Tropical Medicine.
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McLaren Construction ranked second in the April league table after picking up four jobs, the biggest include a £125m extra care project at 3-5 Nightingale Lane in London for Apache Capital and a £70m+ residential project at Hale Wharf Development in London for Canal & River Trust and Muse.
The Kier wins saw the group extend its lead over Balfour Beatty in the 12-month rolling league tables, with Sir Robert McAlpine in third place helped by its £1bn Battersea Power Station win last year.
Among the other big orders in April a three-way joint venture between Sacyr, Somague and Wills Bros shares the £220m A6 Dungiven to Drumahoe Dualling Scheme.
And Ardmore was confirmed for the next £145m phase of its Ram Brewery project in Wandsworth in London.