Legal analysis: generally not, it should be settled according to the contract price agreed in the contract. Lump sum contract, that is, a fixed-price contract, refers to a contract in which the contract price is not adjusted within the agreed risk range, and the contract price already includes risk expenses. There are generally two types: fixed lump sum contract and fixed unit price contract. In this kind of contract, the total contract price can only be changed when the design and scope of the project change. In addition, the total contract price cannot be changed. The price calculation of fixed lump sum contract is based on drawings, regulations and specifications. The two parties to the contract agree on a fixed total price for the construction project, which is guaranteed by the contractor and cannot be changed. If the construction is completed within the original design scope, the contract price will not be adjusted at the time of completion settlement. If the design changes lead to changes in the construction content, in general, if there is a unit price for reference in the contract, it shall be implemented according to the contract; If there is no unit price for reference, it shall be determined by both parties through consultation; If negotiation fails, refer to the average market price.

Legal basis: Article 544 of the Civil Code. If the parties have not clearly agreed on the contents of the contract change, it is presumed that it has not been changed.