What should the slope of a metal chimney be?

A metal chimney might be permitted to run at angle of up to 60 deg. of slope in some jurisdictions. See TRIPLE-WALL METAL FIREPLACE CHIMNEYS for additional sketches and details about angled or sloping metal chimneys and flues and for a fireplace metal chimney inspection checklist.

What’s the maximum angle a chimney can be installed at?

One pair of (two) 15° or 30° elbows may be used in an interior installation to provide an offset in order to avoid cutting of joists and to clear other obstructions. The maximum permissible angle with solid fuel installation is 30 degrees.

How many bends does a chimney need to have?

There must be no bends greater than 45 degrees and there must be no more than four bends in the chimney. If you are using four bends then you must have a soot door between the second and third bend (Building Regs).

How tall does a chimney need to be to support an offset?

The vertical run of chimney above an offset must be supported with an elbow support. Each elbow support will support 15 ft. (4.5 m) of chimney and the maximum length of chimney allowed between the elbows is 6′ (2m). Refer to the Offset Chart 1 on page 13 in these instructions for more details.

What’s the best angle to build a chimney?

Angles of up to 30 degrees are easier to accommodate than angles of 45 degrees. If you can meet your offset requirements by building two slopes of 15 degrees each, so much the better. Chimney manufacturers typically publish offset charts to give installers complete information on how much pipe is needed to construct an offset of 15 or 30 degrees.

Can a chimney flue be sloped or offset?

A fireplace chimney flue can be sloped, but it should only be done if absolutely necessary. The angle of the flue should be 90 degrees or directly perpendicular to ground level if possible. However, it is possible to come off of this vertical by as much as 30 degrees.

What should the angle of a fireplace flue be?

Offsets built into a flue should be as shallow — and as few — as possible. Angles of up to 30 degrees are easier to accommodate than angles of 45 degrees. If you can meet your offset requirements by building two slopes of 15 degrees each, so much the better.