It is possible to install a wood insert into an existing factory-built zero-clearance fireplace. However, there currently exists no UL or ULC standard specific to that type of conversion. The first thing that must be verified is that the factory-built zero clearance fireplace is listed (it must be certified by a competent certification body such as Omni or Warnock Hersey). It must be suitable for use with solid fuel and nothing in the owner’s manual must specifically prohibit the installation of a fireplace insert. When in doubt, check with the fireplace manufacturer. The installation of the zero-clearance fireplace MUST be thoroughly inspected by a professional in order to ensure that it still meets the manufacturer’s specs and code conformity. The chimney must be of at least 1" (25 mm) larger in diameter to accommodate a required continuous stainless steel liner running from the flue collar to the top of the chimney termination.
Never remove parts that serve to insulate the zero-clearance fireplace from combustible material. Only readily detachable parts that are easily replaced, such as damper parts, screens, and doors, are to be removed from the fireplace. These parts must be stored nearby and available for retrofit if the insert is ever removed. Removal of any parts which render the fireplace unfit for use with solid fuel requires the fireplace to be permanently labelled by the installer as being no longer suitable for solid fuel until the removed parts are replaced and the fireplace is restored to its original certified condition. Furthermore, any air vents, grilles, or louvers that serve to create an air circulation pattern around and outside the zero-clearance fireplace shall never be removed.
This is a generic statement, it is true for all inserts and all prefab fireboxes.
In this specific case, there’s a mention on the label regarding this matter indicating NOT to do it. You can still contact the manufacturer and ask them. It will be great to know their opinion on the subject.
Never remove parts that serve to insulate the zero-clearance fireplace from combustible material. Only readily detachable parts that are easily replaced, such as damper parts, screens, and doors, are to be removed from the fireplace. These parts must be stored nearby and available for retrofit if the insert is ever removed. Removal of any parts which render the fireplace unfit for use with solid fuel requires the fireplace to be permanently labelled by the installer as being no longer suitable for solid fuel until the removed parts are replaced and the fireplace is restored to its original certified condition. Furthermore, any air vents, grilles, or louvers that serve to create an air circulation pattern around and outside the zero-clearance fireplace shall never be removed.
This is a generic statement, it is true for all inserts and all prefab fireboxes.
In this specific case, there’s a mention on the label regarding this matter indicating NOT to do it. You can still contact the manufacturer and ask them. It will be great to know their opinion on the subject.