What Gauge Is a Wood Stove Triple Wall Pipe?

Triple-Wall Pipe Construction

• A triple-wall pipe is composed of three layers of different types of metal separated by an air space and a layer of non-flammable material. The DuraPlus brand of triple-wall pipe has a stainless steel inner core, an aluminum second layer and a galvanized steel outer shell. The stainless steel inner liner is 27 gauge, the aluminum layer is roughly 25 gauge and the outer galvanized steel casing is roughly 28 gauge. The outermost layer is separated by an air space and a ceramic blanket that traps heat inside, making it safe to install this pipe as close as 2 inches from a combustible surface.

Definitions

• When installing a wood stove, the choices of stove pipe seem endless, and it's easy to get confused. Should you buy single-wall, double-wall or triple-wall pipe and is there a difference between stove pipe and chimney pipe? The answer to the first half of the question depends on how you plan to install the stove, and the second on whether you already have a chimney in place to connect the stove to. Single and double-wall stove pipe are generally used inside a building to connect the stove to the chimney flue opening in either in the wall or ceiling. The double-wall type allows you to place the stove pipe closer to a combustible wall, which is roughly 6 inches as compared to the minimum of 18 inches if using single-wall pipe. While triple-wall pipe can be used to connect the stove to the flue opening, it is most often used for installations that require a pipe running through the wall to the outside of the building.

Uses

• While triple-wall pipe is expensive and generally reserved for the external component of a wood stove installation, it can be used inside to guarantee a much safer installation than can be achieved using conventional single-wall pipe. Unlike single and double-wall pipe, triple-wall pipe can be passed safely through a combustible wall without the need to install a standard thimble that provides the required 12-inch clearance on all sides.

Safety Considerations

• Triple-wall pipe can be used safely outside to fulfill the minimum chimney height requirement of at least 3 feet above the highest point of the roof. It is also safe to use for an installation that runs the chimney up along an outside wall, as it is weatherproof and can withstand extremes of heat and cold. It's important to remember that, while you can use triple-wall pipe inside as stove pipe to connect your stove to a chimney, single- and double-wall stove pipe should never be substituted for triple-wall pipe intended for use outside.