A vertical roller screen is of crucial importance if you wish to restrict light emissions and optimally control the climate in your greenhouse. Growers using roll-up screens can be assured of the highest possible savings on energy costs. Thanks to a vertical roller screen, the emission of light can be restricted to a minimum and the greenhouse darkened. The screens are attached to the purlin and can be rolled up into the purlin sections of the façades. A separate drive system is needed for each purlin section.