overbuild

verb

1. (ambitransitive)To perform excessive construction on a building or in an area.

   “c. 1962, Philip Larkin on John Betjeman How much more interesting & worth writing about Betjeman's subjects are than most other modern poets, I mean, whether so-and-so achieves some metaphysical inner unity is not really so interesting to us as the overbuilding' of rural Middlesex.”

2. (transitive)To build over or on top of another structure.

   “The architect wanted to overbuild the restaurant on top of an office.”

3. (transitive)To build with excessive size or elaboration.
4. (intransitive)To construct more buildings than necessary in an area.