I'll be installing a high efficiency ZC fireplace into my house soon. I have a wood structure chimney with vinyl siding on it. The rear of the fireplace is completely inaccessible due to the construction of my chimney. There are no access panels or doors on the outside of the house which facilitate inspection and service to the rear of the fireplace. I want to have a large hinged door on my chimney that can be opened so that the complete backside of the FP can easily be accessed, viewed, inspected and serviced if need be. I envision it as a simple low profile plywood door on hinges covered with vinyl siding to blend in with the surrounding chimney. It can be secured using a hidden bolt or two that can be unscrewed in just a few minutes in the event an inspection is desired. Is this done? I've never seen anyone with a feature like this. Anyone know if it's allowable under US building code? Sure seems like a good idea to me, especially for modern high efficiency inserts with blowers and electronics and various air plumbing connections. They're really the wood-burning equivalent of conventional oil or gas furnaces which need periodic inspections, so I don't see why they should be viewed any differently. I don't like the idea of something like that being sealed up forever behind a wall so you can never see what's going on back there (without ripping the whole unit out through the front, anyway).