[35] A payment claim is a claim or an assertion of a right to be paid a progress payment due under a construction contract. Sections 12 and 13 of the Act expressly provide to this effect. It is a cause of action of a very common sort. The Act provides a speedy and informal process by which the cause of action may be determined by way of an adjudication. The adjudication procedure which results in a speedy determination does not alter the nature of the claim: it is a cause of action in contract. The Act provides that the cause of action is to be judged by an adjudicator qualified in accordance with the Act rather than a court. But there is no doubt that the adjudication, once made, is binding on the parties. It can, as I have mentioned, be entered as a judgment of the court and enforced as such. The rather special procedure for dealing with claims for progress payments by subcontractors should not be allowed to disguise the fact that what is in question is a cause of action in contract resulting in a judgment. There can, I think, be no doubt that an adjudication giving rise to a judgment does give rise to a res judicata and, indeed, issue estoppel.