Is it permissible in Islamic law for a wife to ask her husband to transfer to her ownership of a portion of the house she helped build, and is she sinful if she demands the fulfillment of his promise to her, and do her heirs have a right to the house after her death?

The husband must fulfill his promise to transfer ownership of half the land to his wife, as this is considered commendable by the majority of scholars, and many jurists deem it obligatory if it leads to harm or an obligation. Failure to fulfill it is considered a bad marital relationship, especially after the wife's contribution to building the house. If the promise was in exchange for expenses paid by the wife that were not religiously obligatory for her, then she has the right to reclaim what she paid. As for the heirs expelling the husband from the house after the wife's death, this is not permissible. The wife's share is divided among the heirs, or the husband can take their share in exchange for paying its value. There is no religious impediment to transferring ownership of a part of the house to the wife in exchange for her expenses.