Information On Chimneys
First, choose a Masonry or a Metal (Pre-Fab) chimneyA masonry (actual brick or block) chimney MUST have a tile liner when burning wood. Many existing older chimneys are not lined and would be unsafe unless relined.
The materials for a masonry chimney are inexpensive at a lumber yard but labor adds up.
In addition, the 12 to 20 tons of the total chimney weight requires a separate footer.
A metal Pre-Fab chimney does not require a special footer, labor is minimal, and installation is quick and easy, but the stainless steel pipe is expensive.
The modern alternative to a massive masonry chimney is a metal, factory-built chimney. Many different kinds of metal chimney exist. Gas furnaces usually have a Class "B" Vent chimney which is inexpensive but has an aluminum inside, which makes it very unsafe for a wood-burning product.
There are also chimneys specifically for Pellet stoves.
And finally, there are chimneys for wood-burners.
There are some (inferior) types that are associated with specific low-efficiency factory-built fireplace models. These Heatilator, Superior, Majestic and (PreWay) chimneys are not particularly safe and are NOT approved as Class "A".
The ONLY safe metal chimney for wood-burners is called Class "A". There are two varieties: Insulated and Triple-Wall. Until about 1980, Triple-Wall chimneys predominated the market, but since then Insulated chimneys have almost entirely taken over, for very good reasons.
Metal Triple-Wall Class A Chimney relies on free air flow between the walls to maintain safety. To develop a draft in a chimney, you must warm it up. (That's why you build a newspaper fire when starting a fireplace.)
Cold air moving between those walls can chill the inside wall that you're trying to keep warm, so draft can vary.
We prefer Metal Solid-Pack Class-A Chimneys which keep the inner chimney wall warmer, and so the draft is more constant. All of the chimney materials described here and handled by JUCA are Solid-Pack except Amerivent's products.
That page is at: /info/chim1.html