Ventilating synthetic floor covering

The invention provides a ventilating synthetic floor-covering comprising a ventilating support layer and one or more synthetic layers wherein the ventilating support layer comprises a plurality of studs between which narrow ventilation channels are formed even when the floor-covering is compressed in normal use wherein the narrow ventilation channels have a width which is less than a principal dimension of the studs; a ventilating support layer; a production line for use in the preparation of a ventilating support layer wherein the ventilating support layer comprises a support layer and a plurality of studs wherein the production line comprises an embossing roller for embossing the plurality of studs on the support layer or a printing roller for printing the plurality of studs on the support layer wherein narrow ventilation channels are formed between the plurality of studs and wherein the narrow ventilation channels have a width which is less than a principal dimension of the studs; and a method of preparing a synthetic floor-covering according to the invention which method comprises a step of providing a synthetic floor-covering comprising an upper layer and a support layer; and one of the following steps:(a) embossing the support layer to form a plurality of studs between which one or more narrow ventilation channels are formed;(b) embossing the upper layer before embossing the support layer to form a plurality of studs between which one or more narrow ventilation channels are formed;(c) embossing the support layer to form a plurality of studs between which one or more narrow ventilation channels are formed before embossing the upper layer;(d) embossing the support layer and the upper layer at the same time wherein the support layer is embossed to form a plurality of studs between which one or more narrow ventilation channels are formed; or(e) applying one or more studs by printing to form a plurality of studs between which one or more narrow ventilation channels are formed;wherein the narrow ventilation channels have a width which is less than a principal dimension of the studs.