If you use your fireplace regularly during the cold months and you haven’t had your chimney swept for several years then you probably have a lot of creosote buildup. A typical chimney sweep and inspection can take 45 minutes to an hour. Removing a thicker layer of creosote can take more time to remove due to the quantity of buildup that may be present.
You should have your chimney regularly swept and inspected every year (or at least every other year if you only use it occasionally).
📛It’s a fire hazard to allow flammable creosote to continue to build up inside your chimney flue.📛