Heritage buildings are the dynamic linkage by each generation in the continuum of society. Once they are lost a part of history will be lost forever. 3D finite element analysis is carried to estimate the in-plane and out-of-plane performance of un-reinforced masonry wallette strengthened with geosynthetic. From the in-plane test it is estimated that the diagonal shear strength increased to 72 % as compared to un-strengthened panel, while out of plane test gives increase in flexural strength capacity to 129.23 % as compared to un-strengthened panel. Further seismic performance of geotextile as a retrofitting material for heritage masonry buildings using splint and bandage technique is estimated with similar modelling using historical earthquake. The stress contour and deformation results of the retrofitted model shows better control to mitigate earthquake forces.