The present research proposes the application of recycled materials in the construction industry, which is a contribution in the concept of sustainable constructions for the environmental benefit, for example the reuse of plastics. The applications of recycled materials in the use of PET (Polyethylene Terephthalate) recycling from discarded bottles which is not a good final disposal and generates pollution by accumulation and slow degradation. In this research the influence of recycled PET fibers as a reinforcement on a cement matrix was evaluated, cement mixtures were produced to ASTM C31 using Portland cement, coarse sand and stone of ½” with additions of recycled PET fiber at different percentages: 0%, 0.5% , 1.0% and 1.5%. The mixing design considered a water / cement ratio: a / c = 0.62 and a required compressive strength of 210 kg/cm2 for prefabricated applications such as: floo...