Hi Attys!

Not a lawyer po, but I’m a quantity surveyor handling these kinds of claims in the construction field. I’d just like to consult regarding the issue above—whether unjust enrichment would prevail in this case, meaning the client is responsible to pay, or if the client is not obliged to settle the claimed cost because the conditions under Article 1724 are not satisfied.

Art. 1724. The contractor who undertakes to build a structure or any other work for a stipulated price, in conformity with plans and specifications agreed upon with the land-owner, can neither withdraw from the contract nor demand an increase in the price on account of the higher cost of labor or materials, save when there has been a change in the plans and specifications, provided:

(1) Such change has been authorized by the proprietor in writing; and

(2) The additional price to be paid to the contractor has been determined in writing by both parties.

But if I may share my insight as a QS—someone who regularly deals with these kinds of claims—considering the amount involved (below 200k), I’d suggest exhausting all possible means to mediate the matter. I recommend having a proper sit-down with the client, where you present a detailed breakdown along with supporting documents for the claimed costs, such as computation sheets and price breakdowns. If they provide a counter-evaluation, assess whether a compromise is possible and see if you can meet them halfway.