Water Heater Vent Height Above Roof

Direct vent water heaters.

Water heater vent height above roof.

Exhaust gases are vented outdoors through a separate vent duct or through a separate chamber of the same pipe this requires a double wall vent duct. The difference is that a power vent water heater pulls in combustion air from the space around the appliance then uses a fan to propel the exhaust through the vent. Used where the midpoint of a gable roof would have more than 7 8 feet of run to the ridge. Other issue is the bathroom installation which isn t permitted as well unless the water heater closet is sealed from the bathroom area air tight doors and it has a separate fresh air supply from exterior or other areas of the house that can be used for this purpose.

All other gas vents shall terminate not less than 2 feet 610 mm above the highest point where they pass through the roof and at least 2 feet 610 mm higher than any portion of a building within 10 feet 3048 mm. That would be 30 of rise above the roof at the roof plus the 24 if you. Above the highest point where they pass through the roof surface. The 2 10 rule states that combustion vents should terminate at least 2 feet above any part of the roof within 10 feet.

At the hottest point in a gas water heater flue the flue vent connector right above the heater top the temperature is not likely to rise above 350 degf. Here is the nfp11 codes. It is reasonable to assume that higher in the flue temperatures are much lower. Manufacturers recommendations usually take precedence over local building codes but you won t know for sure which takes precedence or what those manufacturers recommendations are.

10 4 1 1 vents installed with mechanical exausters shall terminate not less than 12 in.