Construction work will start in January on the Portobello Square scheme.
Ardmore beat Galliford Try, John Sisk, Leadbitter, Mace and Wilmott Dixon to the job which original contractor Mansell walked away from in July.
Griff Marshalsay, director of Catalyst by Design, said: “From an outstanding short list, choosing Ardmore was based on a number of criteria including their experience and expertise in building high quality mixed tenure regeneration schemes in London. We are very pleased with the selection process outcome.”
James Byrne, the Ardmore director who will be responsible for the project said: “We are delighted with this news and the entire project team is looking forward to working with Catalyst on this unique and prestigious contract.”
Phase 1 of the scheme will deliver 324 new mixed tenure homes – 141 for private sale, 174 affordable and 9 for shared ownership. The scheme also includes re-provision of a public park and retail units.