Woman contributed to looking after household because of promise that she could live in the house rent-free for life. The court allowed her to do so. It held that although non-financial contribution cannot confer a proprietary interest, it may constitute detriment for the purposes of estoppel. Also, once reliance had been proved, the burden was on the other party to show that she had not acted to her detriment.
Per Lord Denning MR: Financial expenditure is not necessary to invoke proprietary estoppel.