Article 664 of Civil Code

1 - If the materials for the work are supplied by the employer, the contractor shall be obliged to exercise the care of an ordinary person in preserving them, to observe the rules of the craft in using them, to render an account of them to the employer, and to return what remains of them. - If the materials or any part thereof become unfit for use because of the contractor's negligence or insufficient technical competence, he shall be obliged to repay their value to the employer, with compensation where warranted.