In my village the old mosque is reconstructed after being demolished,now some people say that out of the original constructed area of the old mosque leave some place for the villagers as walking passage between the mosque and the adjoining house,can such area which was originally the part of mosque be excluded from the new construction.
A place once included in Masjid Sharai will be considered mosque forever, it is unlawful to nullify its position of being mosque. No part of original mosque can be left out at the time of reconstruction.
Allah (Subhana Wa Ta’ala) knows Best
Darul Uloom Deoband