What does GSM mean? The standard measurement for weight of fabrics is Grammes per Square Metre (GSM). This is also used to indicate the quality of a towel. The higher GSM the better the quality. Which GSM? The first question often asked is what weight of towel is best? Towels are measured by GSM: Grams per Square Metre which is the density of the towel (This is the accepted standard.). But, in our view, 550-700gsm is the ideal weight to balance softness and absorbency at a cost effective price. But weight is only important if the cotton is of a premium quality and this has to do with the length of the fibre, otherwise known as the staple. The softness and absorbency of a towel will be greater with increasing GSM, therefore the higher the GSM, the more luxurious the towel. A towel that weighs less than 400gsm will feel thin and this should be the minimum weight for hand/guest towels. Luxury towels fall in the region of 550 – 700gsm and higher in some cases. ( Staple length is a term referring to the average length of a group of fibres of any composition. The staple depends on the origin of the fibres. Natural fibres, such as cotton or wool have a range of lengths in each sample, so the staple length is an average.) Why wash before use? During manufacture, lubricant is applied to the yarn used to form the terry loops, which assists the insertion of the terry loop weft during weaving. This lubricant gives the yarn a slippery surface, which means the loops are very easy to pull. A pre washing process is essential both to remove this lubricant and to allow the ground weave of the towel to shrink in, which tightens the fabric and holds the loops in place. Shrinkage All natural fibres shrink after being washed in water. The percentage of shrinkage varies from 3 to 10%. The amount of shrinkage depends on the fibre and on the washing temperature. The colder the wash water, the better it is for your household linen. Wool is particularly subject to shrinkage when washed.