The monograph describes an attempt performed to manufacture double layer weft knitted fabrics on interlock weft knitting machine. Twenty-seven samples having three denier of polyester micro-denier multifilament yarn (1/75/144, 1/155/288, 2/125 /288) in inner layer and three counts of spun cotton yarn (34Ne, 40Ne, 44Ne) in outer layer as well as in tuck-in layer (35:65 Polyester: Cotton) possessing three loop lengths (3.0mm, 3.1mm, 3.2mm) were prepared. In addition to above samples, two fabric samples with regular polyester multifilament yarn of denier (1/75/36, 1/155/34) had also been prepared to observe the effect of number of filaments in the yarn cross-section. Moreover, one double layer (nylon: cotton 35:65) sample with 70 denier nylon multifilament yarn and one 100% cotton fabric sample with similar construction, have also been prepared to understand the effect of fibre material. All the fabric samples were tested for thermal comfort properties such as air permeability, water vapour permeability, thermal resistance and vertical wicking.