Water Heater Vent Roof Clearance

Use cleaner primer and pvc cement where the vent pipes join the water heater.

Water heater vent roof clearance.

Furnace water heater vent pipe clearance double wall typical listed and labeled double wall vent pipe clearance to combustible materials is one inch but you should always check before installation. Water heaters with power venting come with an electric blower fan often very quiet installed on top of the water heater and can have either vertical or horizontal vent ducts. Cut away the wood that s too close. The top of the chimney should be at least two feet above anything within a ten foot radius of the chimney.

The manufacture even stamps this into the vent. Basement finishing projects are notorious for this code violation. If you are using a b vent typically a double walled air insulated vent for gas appliances typically you ll see a fire clearance stamped right into the metal of the chimney stating 1 inch minimum clearance to combustibles as you ll see in this photo. Since the vent does not rely on the buoyancy of hot air it can be run horizontally to the outside of the house.

Complete the vent pipe installation to the water heater s vent connector fittings. Atmospheric venting refers to a system in which exhaust from the water heater naturally rises out of the appliance s combustion chamber then travels up through a standard chimney style flue. Except for flat and very low slope roofs such as those listed in the table below b vents should be at least two feet above the roof surface as well. Single wall vent pipes cannot pass through a ceiling floor firewall or wall.

Maintain the recommended air space clearance to combustible materials and building insulation. Maximum horizontal section of the furnace water heater double wall vent pipe cannot be longer than 100 of the vertical vent pipe length. For non direct vent applications that is side wall venting only the required clearance is 7 feet. In direct vent applications this clearance distance must be in compliance with local building codes the requirements of the fuel gas supplier for the heating appliance in use and the appliance manufacturer s instructions.

Metal vents that are too close to wood or combustionable materials may cause the wood to burst into flames. Single wall vents should have a minimum of 6 inches of clearance and double wall sometimes called a b vent should have 1 inch minimum clearance. For gas fired water heater vents. Cut a hole through the roof and interior ceiling to accommodate the vent pipes.

See the detailed b vent chimney rooftop clearance table below.