322. Classes of certificate.

In contracts for works of construction, it is common for the parties to confer on an architect, engineer or some other third party a power to issue certificates. The principal purpose of a certificate is to secure payment to the contractor of sums properly due to him under the contract or to express approval of work that has been done. The function of an interim certificate is to provide for payment generally on account to the contractor and the function of a final certificate will normally be to state the final balance due or to express the architect's satisfaction