The problems of building settlements in Port-Said area have been a great concern in recent years. Damages occur in
buildings due to urban development that requires high rise structures to accommodate these extensions. Raft has been
used for many new buildings in Port-Said. Soft to firm clay layers extends down to depths reaching 60 m under the
ground surface. This paper studies the effect of constructing new building beside an existing one. Piled raft has been
studied as settlement reducer and thus to be used as a foundation system in the new building. The typical soil
stratification and properties in Port-Said zone are considered in this study. Parametric study is carried out to examine
influence of new piled raft variables on the existing building. It has proved that the use of piled raft reduces
considerably settlement under the existing building.