Osburn OB01520 - Manual (Page 41)

Soho Installation and Operation Manual
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8.3 MINIMUM CHIMNEY HEIGHT
The top of the chimney should be tall
enough to be above the air
turbulence caused when wind blows
against the house and its roof. The
chimney must extend at least 1 m (3
ft.) above the highest point of
contact with the roof, and at least 60
cm (2 ft.) higher than any roof line or
obstacle within a horizontal distance
of 3 m (10 ft.).
8.4 THE RELATIONSHIP BETWEEN THE CHIMNEY AND THE HOUSE
Because the venting system is the engine that drives the wood heating system, it must have the
right characteristics. The signs of bad system design are cold backdrafting when there is no fire in
the stove, slow kindling of new fires, and smoke roll-out when the door is opened for loading.
There are two guidelines to follow. First, the chimney should be installed up through the heated
space of the house, not out and up an outside wall. Second, the chimney should penetrate the top
of the building at or near the highest heated space.
8.4.1 WHY INSIDE CHIMNEYS ARE PREFERRED?
Venting systems that rise straight up from the stove flue collar provide the best performance.
Chimneys that rise inside the warm space of the house tend to provide a small amount of draft
even when there is no fire burning. This means that when you light a fire, the initial smoke goes up
the chimney and strong draft builds quickly as the chimney flue warms up. Although they are
common in North America, chimneys that exit a house wall and run up outside can cause
problems.