If any promisee neglects or refuses to afford the promisor reasonable facilities for the performance of his promise, the promisor is excused by such neglect or refusal as to any non-performance caused thereby.
Illustration
A contracts with B to repair B's house.
B neglects or refuses to point out to A the places in which his house requires repair.
A is excused for the non-performance of the contract if it is caused by such neglect or refusal.