Question: Zaid took a loan and gave the money towards the building of a Masjid. Thereafter when he paid back the money, he paid interest on the loan he took out. Is his money permissible for the Masjid?
Answer: The money is Halaal for the Masjid. There is no interest money in the money he gave to the Masjid.
Fataawah Mahmoodiyah Vol 22, pg 103