Connecting a Wood Burning Stove to a Chimney

When you are connecting a wood burning stove to a chimney, it is really important to get it right.

Stove pipe

Flue size

Building Regulations state that the flue should not be more than 1″ bigger than the stove pipe.  Most chimney flues are 9″ x 9″ and stove pipes are typically 5″ – 7″.  The problem here, is that even using the larger pipes of 7″ (which are fairly uncommon), then the flue shouldn’t be bigger than 8″.  The only way to resolve this is to have the chimney lined.  This is why, you more than likely need a liner when you have a stove installed.

Unlined installation

If your flue is only 1″ bigger than the stove pipe, then as long as it passes a flue integrity test (showing that it’s not leaking) you can, theoretically, install the stove without a liner.  However, you musty make sure there is adequate sweeping access, if not it will be condemned on the first visit from a certified sweep.


Finally while it is only a cosmetic thing, it is intensely irritating.  Look at the point where a flue pipe enters the wall.  Almost without exception, it will be surrounded by cracks and bits of plaster falling off, and just like every other area, stove installation Cambridge is littered with such examples.

The cause is that whoever installed the stove forgot that the flue pipe would expand and split the plaster.  Really the pipe should be surrounded with a flexible, heatproof seal that allows such expansion and contraction without splitting the plaster.  For the customer, this is a right royal pain in the fundament, as they either have to have the plaster work cracked and broken, or they have to  replaster and paint around it every single year.  Of course sometimes even though the stove is incorrectly installed, the expansion does not crack the plaster

Connecting your stove to a chimney

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Wight Initiatives Ltd,
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Registered in the UK # 7725 203
VAT # 218 3459 04