The minimum clearance to a perpendicular wall extending past the face of the fireplace is one inch 25 mm.
Minimum gas appliance vent clearance from roof.
Gas fireplace direct vent termination cap clearance distances clearances between the gas fireplace exhaust vent and other building components or features.
Number 2 is a vent for an exhaust fan like those found in bathrooms and laundry rooms.
Appliances designed for natural draft venting and incorporating integral venting means shall be located so that a minimum clearance of 9 inches 229 mm is maintained between vent terminals and from any openings through which combustion products enter the building.
Each gas appliance must use a separate vent system.
Stack vents may give off sewer gas so they should not be located within 3 feet of an operable window.
Common vent systems are prohibited.
3 chimney vent caps larger than 12 must be located at least 2 feet above the highest point and 2 feet higher than any portion of the building within a horizontal distance of 10 feet.
Venting systems vent connectors slope in ft upward to chimney vent not smaller than appliance flue up to 2 sizes larger than appliance flue length depends on type for single appliance single wall 75 of vent height b vent 100 of vent height 18 inch diameter for multiple appliances 34.