This section is from the book "Cyclopedia Of Architecture, Carpentry, And Building", by James C. et al. Also available from Amazon: Cyclopedia Of Architecture, Carpentry And Building.
By the ordinary building contract, the contractor enters into obligations with the owner only. To the architect, who is not a party to the contract, the contractor owes no contractual duties which the architect may enforce in law or in equity. However, by the contract it may become the builder's duty to the owner to obey the architect's instructions, to do the work to his satisfaction, and the like. These duties of the builder can be enforced only by the owner. Therefore, according to the rights of the owner, the architect may be said to be entitled to obedience as provided in the contract.