There are many geotechnical failures in recent times especially due to the closeness of two structures in urban areas. In order to propose a plan for safety of structure there is a need to provide strong guidelines on the influence of neighbouring structures. Further, improper excavation near the existing structure also leads to many failures. The study investigates the behaviour of existing strip foundation due to excavation in adjacent site under unconfined conditions. The influence of depth of excavation (D) and distance between existing strip foundation and excavation (L) on ultimate bearing capacity (Qult) and settlement under the strip are investigated. PLAXIS 2D is used to perform the numerical analysis. The investigation is carried out to study the effect of excavation, factors influencing the performance and possible remedial measures. The numerical results confirm the influence of excavation on existing strip foundation. This study stresses the necessity of preparing guidelines for constructing new structures adjacent to existing structure.