The weavers made flat woven rugs – called Kilms – before they discovered the art of knotting. Unlike knotted pieces or carpets, the kilms– what is called the slit-tapestry technique – are quicker and easier to produce and light in weight for easy transportation.
They are weaved double-faced by weaving different coloured weft threads in and out of warp. This results in creation of small holes in the rugs where blocks of different colours meet. These holes were almost invisible in well-produced pieces. Their lack of piles made them less warm as compared to knotted rugs, hence, the kilms were often used as wall hangings and bed covers, cushion backs and handbags and not as floor coverings. During 16th and 17th centuries, in Safavid Persia, some of the wonderful silk kilms were woven in the workshops in Kashan and Esfahan, which produced pile rugs and sophisticated Senneh wool kilms.
Another well –known rug type is the sumakh, a form of brocading; these are associated primarily with Caucasian village weavers. Like kilms, sumakh also has no pile but they are woven more tightly and are tougher. A basic network of warps and wefts are used to produce them along with additional coloured weft threads, which are woven into this framework in shorthands to create patterns. The ends are left trailing on the reverse piece. As a result, the sumakhs are not reversible in the way kilms are, since the back is a shaggy mass of wool creating an insulating layer that make then considerably warmer.