The disparity between plastic production and recycling rates presents significant environmental and health challenges. Low-Density Polyethylene (LDPE), a common single-use plastic, often accumulates in landfills due to limited recycling infrastructure. This study investigated the feasibility of utilizing LDPE waste in brick production by evaluating the performance of bricks incorporating plastic as a full cement replacement (plastic brick) and as a partial aggregate replacement (eco-brick), compared to conventional concrete bricks. Experimental testing assessed mechanical, thermal, and acoustic properties. Results show that the difference of plastic brick to the regular and eco brick is significant in terms of the three properties. Plastic bricks exhibited the highest compressive strength at 13.835 MPa, exceeding the minimum requirement for load-bearing masonry units (11.7 MPa). However, the dense structure of plastic bricks resulted in lower acoustic performance, with a Sound Transmission Class (STC) of 27 compared to 39 and 40 for regular and eco-bricks, respectively. In terms of thermal performance, plastic bricks showed a greater temperature difference between their interior and exterior surfaces, suggesting the lowest thermal conductivity among the three bricks and potential for thermal insulation. While these findings indicate the feasibility of utilizing plastic waste in brick production, further research is necessary to evaluate the long-term sustainability, environmental safety, and accessibility of this approach.