The raw material of a fabric has a substantial influence on its functional aspect. However, the fabrics used for clothing manufacture should offer comfort, protection, ease of maintenance, durability and aesthetics. This study aims to compare the properties of knitted fabrics made of recycled polyester by employing the Chauvenet criterion, factorial design and statistical analysis to determine which raw material composition provides more functionality to the final product. Knitted fabrics (jersey fabrics with statistically equal weights) made of two types of yarns, namely 80%-polyester/20%-recycled-polyester and 50%-recycled-polyester/50%-cotton, were tested. For the finished fabrics, the following tests were performed: weight, pilling, burst pressure, elasticity and elongation, moisture absorption, and dimensional change. The response surface graphics were analysed to determine the optimum regulation value for the knitting machine to manufacture fabrics with statistically equal weights. The best results were obtained with knitted fabrics produced with 80%-polyester/20%-recycled-polyester yarns.234 1924