Keep a minimum 6” clearance around the vent termination cap to all non-combustible materials. If the top of the shroud is enclosed, keep a minimum of 10” clearance from the top of the termination to the bottom of the shroud. Keep 4” openings at the bottom of the shroud to allow for proper air flow within the space to help release the products of combustion through the top or sides of shroud. The center of the opening must be aligned with the center of the termination cap, see X & Y for examples. All surfaces of the chimney shroud which are exposed to the termination cap must be non-combustible.