Non-certified installations: Maintain 9" from the outside surface of the 3" flue pipe to combustibles without shielding. This can be reduced to 3" with proper flue shielding covering the entire run of pipe beside the combustible surface.

Certified installations in Canada and the U.S.: Maintain at least 18" (45.72 cm) from the outside surface of the 3" flue pipe to any combustible surface. In Canada, shielding does not reduce the 18" pipe clearance. For U.S. installations, use the 18" clearance specified in the certified manual unless a reduction is explicitly approved by the authority having jurisdiction. Stove shielding and pipe clearances are separate requirements.