Typically a fabric will last 6-10 years, depending on how it is cared for and the environment that it is exposed to. Improper water chemistry plays the biggest role in early deterioration. Fabrics that are cracked, have holes, or look generally worn out, should be replaced. From a distance the cover may look not too bad, but upon closer inspection you may notice deterioration which can affect the covers performance and safety. Please be sure to inspect your cover and contact the pool patrol if your cover needs replacing.