Raw materials and products environment friendly has led many authors to develop the area of bio-construction, especially in civil construction, using alternative materials to obtain new achievements. PET (Polyethylene terephthalate) bottles, widely used worldwide, have made it possible to produce very ambitious technological products for their energy and economic efficiency. This study is based on the application of discarded PET bottles for application in ecological building bricks. For this, samples with different PET percent were prepared. The samples were prepared in triplicate. These samples were subjected to tests to verify the optimum setting time/PET ratio. The tests were performed according to international standards and compared to the values of conventional bricks.Keywords: Environment friendly, set-up tests, bio-construction.