This study focuses on PET waste reduction worldwide by looking at the application of these polymeric materials in the construction and building industries. An effective application of PET wastes will reduce PET pollution, especially in water bodies. Due to its rising cost, it can partially replace the conventional binder used (cement).Bricks were made in the conventional cement-sand and PET-sand, and a total of 72 cubes were produced for different mix ratios of 1:1, 1.5:1, and 2:1. Their properties like particle size analysis, water absorption, slump testing, and compressive strength were investigated and compared.The particle size analysis showed that the sand was well-graded with a Cu of 3.41 and a Cc of 1.07. The results of the water absorption test showed that, in both series and different mix ratios, the PET-sand interlocking blocks had a lower sorptivity (percentages of 2.02, 2.72, and 4.20) than the cement-sand interlocking blocks (percentages of 0.91, 2.40, and 3.31). The mixtures produced a 70 mm, 50 mm, and 80 mm slump for 1:1, 1.5:1, and 2:1, respectively.The maximum compressive strengths in cement-sand interlocking blocks were 13.89 N/mm2, 17.34 N/mm2, and 21.06 N/mm2 in the 1:1, 1.5:1, and 2:1 respectively. Although the results showed that the compressive strength of PET-sand interlocking bricks was lower than that of cement-sand interlocking bricks, it can be useful in a low-density carriage road.