Specifications include, but are not limited to: Vendor will remove the entire existing boiler exhaust stack this includes everything from the boiler and through the roof approximately 30 lineal feet. Vendor will fabricate approximately 30 lineal feet of boiler exhaust stack to include: Metal utilized must be welded carbon steel pipe and must have a minimum thickness of 16 gauge. Boiler exhaust stack to be fitted with a rain cap, pipe flanges, and feature a square to round fitting above the roof. Boiler exhaust stack to be a diameter of 16 inches Boiler exhaust stack will need to bolt into existing mounting plate located on boiler. Vendor will install new boiler exhaust stack starting at boiler and exiting through the roof. Vendor will utilize existing penetrations for new boiler exhaust stack through any walls, ceilings, or roofs.