According to the Chimney Safety Institute of America, the National Fire Protection Association Standard requires that chimneys be cleaned, inspected and repaired at least once every year. Less frequent cleaning may allow animal nests, structural damage and creosote buildup to go undetected. Creosote buildup is known to cause cancer and increase chances of a fire.
Waiting to have your chimney swept doesn't just compromise your home's safety --- it may cost you extra money as well. Chimneys that are not well-maintained may accumulate a thick layer of hardened creosote that can only be removed through the use of chemicals. Many times, these cleanings require three appointments instead of just one.
Surprisingly, summer is the best time to have your chimney swept. Not only will you avoid the long waiting lists that often start in September, summer cleaning will help reduce allergens within your home.