Congregants standing ahead of the imam during prayer
A mosque measures 64 sq. ft. in area but lacks a rest room and living quarters for the imam assigned to it. One of the congregants donated an adjoining piece of land located to the right side of the mosque. The problem is that the ground level of this piece of land is lower than that on which the mosque is built, and if this area is added to the mosque, the first rows of congregants will stand ahead of the imam. What is the stance of Islamic law on this?
According to the majority of scholars, it is impermissible for the congregants to stand ahead of the imam. There is no harm if the congregants pray on a higher level in relation to the imam or vice-versa. The important thing for the validity of congregational prayer, is that the congregants do not stand in front of the imam; they have to be in the same place as him to be able to follow his motions by seeing or hearing him or hearing the muballigh [the person who repeats the words of the imam loudly so that everyone in a large congregation can hear him]. However, there are some differences of opinions held by the jurists on this issue.
Based on this and in reference to the question, expanding the mosque in this manner is recommended and considered a pious deed. There is no harm if the ground level of the extension is lower than that of the mosque. Those praying in the extension must be careful not to stand ahead of the imam until the integration is complete and the place becomes a single unit surrounded by a single wall when it will then become possible to move the imam's place ahead of the entire congregation.
Allah Almighty knows best.