Awnings, like anything else, need some attention every now and again to maintain their quality! It is not recommended to use any detergent whatsoever! Even washing up liquid can cause major damage to your fabric so avoid this. If you must use something then it is possible to use a very mild soap. You will need to lather this in your hands and then apply it delicately with your fingertips and use a brush to take it off. Brushes used to clean your car are ideal!