Duration between cleaning and sealing depends on a number of factors as well as personal preference. Environmental factors, such as exposure to sun, moisture, over hanging trees, and exposure to salt will have a major influence. Other factors such as use, pets, children, and cleaning tendencies will also have an impact. At the end of the day there is no perfect answer though every 2-3 years is common practice with some people choosing to reseal sooner and others waiting a little longer.