I both agree and disagree to move to a smaller house when the kids are grown and have a family of their own. It is economical to stay in a smaller house for the maintenance is also smaller. However, there is the sentimental value of the family home that in the future would be considered as the ancestral home. If you have enough funds to tide you over for your old age then it is better to retain your big house. But if on the contrary then I guess you just sell and find a smaller house in the suburbs. That would leave you with more cash.