It is not permissible to take anything from the area of the Masjid to add to the mentioned house, because the basic rule for a Waqf is that it should be kept as it is. It is not permissible to change a Waqf from a superior status to a lower one. If the house is not suitable for habitation, you could refer this matter to the courts for them to look into this matter and issue a judgment according to the Shari‘ah (Islamic law), pursuant to what is observed there. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.