Kier has won an £18 million deal to build a new academy in Greenford for Ealing Council.
The company said it had been awarded the contract for the North Ealing CofE Academy though the Academies Framework.
The school is scheduled to open in September 2013, subject to planning permission, and will be run by the Twyford Church of England High School and the London Diocesan Board for Schools.
It will have places for 1,200 girls aged between 11 and 16, in addition to housing a sixth form for 250 students and a centre for children with special educational needs.
Under current proposals, the local community will also be able to use the school’s facilities including its full-sized sports pitches, flood-lit hard playing surfaces, indoor sports hall and activity studio.
David Archibald, executive director, children and adults at Ealing Borough Council, said: “We have worked closely with central government and the Twyford Church of England Academy Trust to get to this stage and we want to make sure that local people are given a chance to have their say too.”