A variety of different ways to tie shoelaces

When shoelaces are knotted in place, they can curl or flatten. This is mainly to prevent the LACES from coming undone. In fact, the lace is narrower inside the knot than at the loose end, which cannot make itself smaller and slide through the knot.

In general, flat tubular lace is more likely to knot than round lace with a core because flat lace is more likely to curl in the knot. However, most shoelaces are round and have a cotton core, especially boot LACES. In order for a shoelace to be securely tied together, the core inside the shoelace must be soft and compressible. The second factor in shoelace loosening is the slip of the knot itself. This is due to lack of friction. Cotton shoelaces have a rough surface and are more reliable for tying knots than polyester, the most commonly used yarn in shoelaces. In addition, lace can be either smooth or rough-faced, which can also affect performance. Finishing processes are available, including waxing and silicone treatments to enhance friction and prevent knotting and slippage. These are all important design factors in making hiking boots LACES.