Redrow has applied to Barnet Council to build another 1,200 apartments at the former Hendon police training site, which is being turned into housing.
The scheme, which launched in 2016, has seen 1,350 homes sold to date, with a fifth of the new community now moved in.
The latest application will see the number of homes on the 47-acre site increase from 2,900 to approximately 4,000. The new apartments will be located in the southeast corner of the site.
Redrow regional chief executive Mark Parker said: “Colindale Gardens has been exceptionally popular since we launched just over three years ago, and it shows no sign of slowing down with an average of four sales a week.”