Could you inform us if it is permissible to hire out the upper floor of a Musjid for catering for events such as Nikahs and wedding functions?

Answer

According to the Shariah, the space above the Musjid as far as the heavens and the space below the Musjid right into the bowels of the earth are also the Musjid. It is not permissible to conduct any activity in the upper floor of the Musjid in exactly the same way as it is not permissible on the ground floor of the Musjid. A Musjid is Waqf property dedicated exclusively for the Ibaadat of Allah Ta'ala. No portion of the Musjid may be hired out even for a noble purpose such as Hifzul Qur'aan. To a far greater degree will the prohibition apply when the Musjid is hired out for haraam wedding functions.

Just as it is not permissible to have wedding function, etc. in the Musjid's ground floor, so too is it not permissible to have these functions on the upper floor of the Musjid. Wedding functions, even a 100% Shariah-Compliant Masnoon Walimah is also haraam in a Musjid whether on the ground floor or the upper floor.