How to fit stove pipe

Single Wall vitreous enamelled stove pipe is known as a connecting pipe and is highly advised for every installation of a wood burning stove. Connecting directly into your log burner's flue outlet, a minimum 500-600mm length of Single Wall pipe should rise vertically before connecting to Flexible Flue Liner if going directly up an existing chimney, or to insulated Twin Wall flue pipe if you need to pass through a wall or ceiling or route your flue pipe externally. This vertical pipe at the start of the flue system allows the gases within the flue to start rising and the finish of the vitreous enamel pipe won’t tarnish with the heat generated so close to the stove.

Single Wall vitreous enamelled stove pipe should only be used internally due to its lack of any form of insulation within the pipe - If you need to pass through a wall, ceiling or if your flue pipe is running externally, you should in all cases use insulated Twin Wall flue. No insulation means firstly, Single Wall stove pipe can run extremely hot and reach temperatures of 500°C plus, so passing through any surfaces poses a very real fire risk. And secondly, there is nothing to stop cold air meeting the hot air within the system, causing condensation which will corrode the pipe and rapidly cooling the system causing gases to drop instead of rise. Using insulated Twin Wall flue pipe significantly reduces these problems.

When installing stove pipe, you must always ensure that the spigot end (the tapered or reduced diameter male end) is pointing downwards. All flue pipes connect inside the pipe or connection below as condensates in flue pipes are unavoidable and installing with the spigot end facing upwards creates ridges in your system that water can collect and sit in, which will greatly reduce the life of your stove pipe.

You should seal every joint from the outlet collar of the wood burning stove all the way up with Fire Cement and ensure that all seals are not leaking by testing with Smoke Pellets. Any leaks in the flue system can be very dangerous and result in a loss of pressure within the flue.

You can increase the diameter of your flue system by up to 1 inch at a time from the diameter of the flue outlet on your wood burning stove but by no more. You can also not reduce the diameter at any point in your flue system, to ensure that the updraught will be sufficient for your log burner. Reducing the inner diameter of a flue as it travels upwards will bottle neck the gases within, which will cool and in turn deposit soot, potentially blocking the chimney and leading to a chimney fire.

If you have any further questions about stove pipe, then do call us on 01376 804649, email us at [email protected] or leave us a comment on this post, and we would be pleased to help.

Wood Burning Stoves and Flues

10th May 2012

Comments

Glen says:
6th March 2019 at 12:53 pm
Just read your advice – very helpful in saying which way up the flue should go. Many thanks

Andrew Shuttleworth says:
26th July 2019 at 3:35 pm
Good to hear! Installing the first length of flue pipe is not uncommon but by doing so, will throuw the entire system out. Male ends downwards into the stove on all occassions

Jim says:
9th November 2019 at 8:08 am
When I attempt to fit spigot end of flue pipe into stove it is a loose fit? Do I require some sort of bracket?

Andrew Shuttleworth says:
31st January 2020 at 10:32 am
Some connections can be looser than others as there are many manufacturers of stove pipes and many manufacturers of stoves and the chances of them all fitting together perfectly is slim. It is quite common to have a slight gap around the pipe and this simply requires filling with Fire Cement and Stove Rope: https://www.glowing-embers.co.uk/flue-accessories-fire-cement-c-70_89_96?zenid=66ik8tspg9aj9ckdsua145ael6 https://www.glowing-embers.co.uk/stove-accessories-stove-fire-rope-and-adhesive-c-160_193?zenid=66ik8tspg9aj9ckdsua145ael6

Paul Olivier says:
29th October 2021 at 1:58 pm
As far as i am aware there is no minimum length given for stove pipe connecting to a flexible flue liner, Can you think of a reason why a stove manufacturer states that a 1 metre length of stove pipe should be used? I have been trying to find out from the manufacturer with little success

Andrew Shuttleworth says:
9th November 2021 at 3:14 pm
Flexible Chimney Liners are not designed to be connected directly to the stove outlet collar due to the heat emitted at that connection and therefore, it is advised to distance this. Typically this is done with 1000mm stove pipe to get through the register plate and into the chimney cavity.

Raymond haughey says:
21st November 2022 at 7:27 pm
Can the stove pipe be cut down as the gap between stove and register plate is only 350mm and cannot get further up chimney

Andrew Shuttleworth says:
22nd November 2022 at 10:13 am
The Easy Fit range of vitreous enamelled pipes can be cut down from the female end only as they maintain an accurate diameter for the entire length of the pipe. Please do not cut from the lower male end up though as you will lose the tapered connection. The Economoy range of vitreous pipes and any twin wall brands cannot be cut.