Is it permissible for a worshiper to intend to dedicate the reward of his prayer to his deceased mother when using a prayer mat that belonged to her?

If the mother dies, her cloak becomes an inheritance for her heirs. If the daughter takes possession of it and makes it into a prayer rug as an endowment (waqf) for her mother, it is hoped that the mother will receive reward as long as the rug is used. As for dedicating the reward of prayer to the mother, there is a difference of opinion on this. The preponderant view with us is that the reward of prayer does not reach the deceased. Rather, the reward of charity, fasting, and Hajj reaches them. Some scholars, however, permit the dedication of the reward of prayer, and among them are those who restrict this to supererogatory (nafl) prayers.