How Far Should A Flu Be Installed Above A Roof

450 mm 18 in.

How far should a flu be installed above a roof.

This specification makes sure steep roof slopes are cleared. Install no more than two elbow pipes at 45 degree angles if running the pipe through a chimney stack. Match the vent pipe to the furnace maker s recommendations either sheet metal or vinyl. Keep flue pipe as straight as possible for horizontal runs.

The top of the chimney should be at least 3 ft 0 92 m above the roof surface. For gas vents or a type l vent this distance above the roof surface must be at least 2 ft 0 61m. Minimum clearance from combustible material. 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.

If the pipe is farther than 10 feet from the roof peak it must be 2 feet above the highest point of the roof within 10 feet. Place vent support straps along the pipe every 8 feet if it s more than 25 feet long. Vertical blue line along the left side of the chimney in our photo. Set the collar with the wide flange at the bottom on the surface of the roof.

When installing a new twinwall flue system if the flue exits the roof within 600mm horizontally from the ridge high point of the roof then the flue must extend a minimum of 600mm above the ridge. Roof sheathing is attached to the roof framing trusses or rafters and provides the nail base for the other components of the roof system. Next roofing underlayment often made of building paper or felt is installed as the first weatherproofing layer for a pitched roof. The minimum clearance may be reduced by 50 percent to 225 mm 9 in if suitable shielding is installed either on the pipe or on the combustible surface.

In other words the highest point within a 10 foot circle of the pipe.