How to fit a log burning stove?

My Story

I get calls all the time from customers who have the skills and are wanting to fit their own log burners to save themselves some money.

As well as calls from some people who have tried to fit their own stove and its gone wrong and we go and help sort it out.

We also get a lot of clients who have recently moved into a new home that has had a log burner fitter by the previous homeowner and they just don’t quite feel safe and often for good reason, that’s why I would like t share with you how we do it.

While I would always recommend getting an expert in, it is something that for someone with a good level of building experience it is defiantly not impossible.

In fact, that’s how I started out, by fitting a log burner for my Mum and Dad. I had forgotten to get fire cent and thankfully the local log burner shop owner Ryan kindly came around to drop off some fire cement for me.

I invited him in to see my work thinking that he would be able to find a few faults, but instead, he offered me a job. I had previously spent 15 years previous working in construction, learning everything I could about all the many elements home construction entails, which gave me the ability to be able to break down the process into small simple steps.

The first Install that i completed that set me on my log burner journey!

These small steps I have broken down for you below, I have tried to be as clear as possible and have put in as much information including tips and shortcuts.

I would love it if you could let me know if this information is useful, send me pics and your stories I would love to hear from you. Also if its missing anything please let me know I would be more than happy to help.

The first job

Tools -Screwdriver, hammer drill

Materials- CO Alarm

Fit a Carbon monoxide alarm, this is always the first job as your well being is everything.

This needs to be away from corners of the room at least 350mm, away from windows, higher than the stove and in a 3m radius.

Who do I need to inform before I fit a wood burner?

If you’re not using a Registered Hetas installer then letting your local council’s building control representative know that you’re planning on fitting a stove is a good idea before you get started. This is so that you can get it signed off at the end, enabling you to get a certificate that will mean it’s legal but is also important for your home insurance and most importantly safe.

Removing a Gas or electric fire

When it comes to removing an existing gas fire you will need to get a registered gas engineer in to cap off the gas as far always possible, the actual distance will vary depending on the stove guidelines. The same applies to an electric fire; make sure to get a qualified electrician, not your best mate!

Opening up a Chimney breast

Opening a Chimney breast that is on the outside of the home, follows the same principles in reverse.

ToolsLump Hammer, Bolster, Bucket, trowel, pointing iron, gloves, brick saw, SDS hammer drill, level, dust sheets

Materials– Sand, cement, concrete Lintel, (extra lintels if widening the chamber), replacement bricks, slate to pack the lintel

The doc j regulations state that the opening of the chamber can be as large as you like ensuring that you leave 200mm jams either side of the recess.

First thing there will be a lot more rubble coming out than you expect, so have somewhere in mind to put it like a small skip.
Remove all the bricks and the fire old back, back boiler etc. that is in the way of your original opening, once this is done you can then assess whether it will need any more taken out and whether it will need to go higher or wider to get your desired stove in.

Once this has been assessed, draw you target opening size on the wall and chisel off the plaster around where you need to remove about an inch bigger than needed you can then see the brickwork which will give you an idea of where is going to be the best place to start.

Remember to chisel and plan where the lintel is going to go, this will need 150mm, on each side sitting on the jams.

Its important that if you are widening the opening to work out how you are going to support the internal chimney brickwork, it is most likely tied in to the back wall but it will still need to be supported, which will mean two lintels sitting on top of your the front lintel tying into your back wall to support the gather brickwork  you will then need to rebuild the supporting walls, be sure to build on a solid foundation.

Be careful when working near the back wall if it if a party wall (shared with your neighbour) as you don’t want the neighbour knocking on your door saying that their kitchen is falling to bits. I would recommend not using the SDS hammer drill for this bit.

Be sure when widening to leave space for the chamber to be boarded/ rendered.

Choosing the hearth

The heath must be made from a non-combustible material, this can be anything from polished concrete to a tiled hearth, we personally like to recommend granite (either polished or honed) as it’s really hard wearing, it looks expensive (well it is), plus it’s easy to clean.

There are many different types of slate, which can look great I do however find this will scratch too easily.

There’s a wide variety of hearth types

Glass hearths both clear and smokey can look really good on a wooden floor or carpet. The smokey look hides any dust that might find its way underneath.

Fitting your hearth

Tools- Level, builders trowl, disc cutter

When it comes to fitting the hearth make sure to find out whether the stove needs a constructional hearth (a 125mm slab of supporting concrete), usually already there when working in an existing chamber or just a 12mm hearth which can go straight on top of any surface. A typical constructional hearth would come out 500mm in front of the chamber jams (the pillars both sides) and 150mm each side.

The Jams on this install are more than the minimum 200mm

Some stoves won’t need a constructional hearth. Unless they are in a chamber then all stoves do need a constructional hearth. But as discussed most chambers already have a constructional hearth built in.

Each stove is different so check the requirements. Normally a superimposed hearth (a decorative hearth) will cover the constructional hearth to create a beautiful finish, this can be anything as long as its non-combustible.

You are looking for a minimum hearth distance of 225mm in front of a stove for spillage.

It’s best to fit the hearth in two pieces one that sits in front and a smaller piece that you can cut down to size to put in the back, making sure that the machine cut polished edge is the one that you butt up against the front creating a seamless join.

Cutting the hearth to size can be done with a disk cutter or grinder using a diamond blade, or it can be ordered to size to save time and effort.

Cutting hearths on site

I find it best to bed the back hearth down after the front hearth is in place to help get the right height using a mix of sharp sand and cement (4-1) making sure to put down at least one spot under each corner and one in the middle. Gently tap down the back hearth until it is in place.

If you want it to set quickly so that you can keep working use a rapid set cement.

Board or render the Chamber

Tools- Hawk and trowel, bucket, level, square

If you are lucky you will find that once you have excavated the chamber it is perfect in every way which means this step will be easy as you can just clean it up and leave it with a rustic brick effect or maybe paint it. I have found that if the brickwork isn’t that great a coat of black paint really can hide the imperfections and look goods great once the stove is in front.

Lining a chamber with a non-combustible board can give it a great finish that can be painted or tiled, chamber boards come in many designs to suit your needs such as brick effect, reid effect, plain or tiled. The great thing about this is it looks great and saves you a lot of time and mess you just need some heatproof board adhesive.

Brick effect Internal Chamber boards

First, make sure to clean the walls you are sticking from dust to ensure good contact and make sure its square and plumb by using a level and set square.

 Once you’re happy that the boards are stuck in the correct place you can fill around the edges with some gypsum hardwall. Scrape back flush the hard wall with the boards

If you have already laid the hearth this will give a nice neat finish.

Chamber boards in place, these can be painted or tiled onto.

An alternative option is to use a plaster render, I would recommend 5-parts plastering sand, 1-part cement, and 1-part hydrated Lyme. This mix will stop it cracking in the heat. You can also buy a ready mixed heatproof render/screed. You can also get heatproof render ready made.

Don’t forget to use metal angle beads, not plastic.

Here the chamber is rendered

Depending on your abilities you will probably find that the render option is going to be a steep learning experience, as it can take years of practice to be perfect, but if you don’t mind the rustic look then give it a go, hey you can always board it afterwards if need be.

You’re now ready to plaster the chimney breast.

Plastering the chimney breast

Tools- Hawk and trowel, brush, bucket

For this, I would call in a professional and get the whole chimney breast done in one go (and possibly any other bits of plastering you have been putting off, that needs doing in your home).

If you are determined to give this a go then I would recommend plastering just the bit around the opening.

Prep first with some watered down PVA over the hard wall,

while this is going off nail your thin coat angle beads around the opening, use a pair of tin snips to cut to size.

Then plaster away from the angle beads. Use a hawk and trowel and spread the plaster, do this it in two coats, to fill in any dips you might have missed,

Put more plaster on than you need and then take off the excess and then as it starts to set use a clean paint brush to feather in with the existing plasterwork while trowling up (smoothing off the plaster for a final time and filling in any dips).

Brick side jams and a plastered top half on this false chimney breast.

It’s worth using heatproof plaster around  the opening to stop the plaster cracking

Fitting the mantel

Tools -SDS Drill, Drill bits,

When fitting any form of a wooden mantel or surround that is made from combustible materials, be sure to check that it is not going to be too close to the stove. You can do this by downloading the manufactures guidelines online or by calling them up, it’s always best to get it in writing though.

When fitting a stove pipe, for instance, the distance to combustibles is 3 times the diameter, so with a 6-inch pipe, any combustible materials would need to be at least 18inchs away.

Real Oak beam with large split

I personally recommend getting geo caste mantels that are made from non-combustible materials, as these look the same if not better than the wooden ones which I have found can often come with massive splits along them where they have been dried out to look old too quick.

Oak surround

You might find that you have to put a wooden mantel up higher than you planned because of distances to combustibles. I personally think mantels look best at lintel height.

If you decide to go for real wood and need to get over this problem then you can use a heat shield or possibly use some twin wall stove pipe to reduce the distances.

The twin wall we use has a distance to combustibles of 60mm and a heat shield can reduce the distance in half, it needs to be non-combustible and needs an air gap of 12mm behind it.

Personally, i don’t think this looks nice as it can normally be seen.

Get the Chimney swept

Tools- Chimney brushes,

This is important to do before installing your Flexi-liner.

The reason that you will need do this is to make sure that there are no hazardous soot particles left in the chimney that could cause chimney fires in the future when the new liner heats up.

Get your chimney swept pre-install.

Access to Fit a liner for a wood burning stove?

Tools- Ladder, roof ladder

The first thing to do is to carry out a risk assessment.

Check that the access to the chimney pot is going to be safe and work out the best way to access the chimney.

We use either a ladder or a ladder and roof ladder combination, a cherry picker or the safest and most preferred method which is a professional erected scaffold.

Scaffolding is the platform of choice for most installs

Using a Cheery picker for Installing a liner can save money and time

Ideally, you want to be able to be able to put the liner down from waist height.

Always make sure that you are safe, use a harness when working at heights.
When working off ladders strap the ladders to the chimney stack or anchor into the wall if it’s safe to do so, some stacks can be really wobbly.

Which Flexi-liner should you buy?

316/316 grade or  316/ 904 grade or a 904/904 grade.

Basically, they are double skinned with an outer and inner grade stainless steel, a 316 isn’t going to last as long as a 904 grade but the lifespan really depends on how much you use it and what you are burning, for instance, a 316 will be fine if burning the right wood but it might not last so long if burning coal.

The 316/316 liner comes with a 15-year warranty, the most popular liner, it does the job and if your burning only suitable wood it will be perfectly fine.

Liner for a wood burner stove coiled up

The 904/904 has a 30-year warranty and is made from tougher grade steel, it is heavier and more robust.

Remember that choosing a Defra Stove will mean that a 5inch liner can be used; this can make your life a lot easier when trying to get a heavy 10m Liner down an awkward chimney.

Putting the Flexi-liner down the Chimney

Tools- Rope (that is twice as long as the chimney) a 5 or 6inch Nose cone,  screws, strong tape, cut-proof gloves, Flathead screwdriver

First work out which way up the liner needs to go this can normally be worked out by the printed writing on the sides and a printed arrow which will point up, the direction that the smoke goes. you can sometimes tell by running your fingers up and down the inside of the liner and imagining that its a slide, one way will feel rough and one side will feel smooth, I like to imagine that if it was a slide you would want to slide down it not up it. If in doubt ask your supplier.

Putting a liner down a chimney can be a difficult prospect, be sure to wear a safety harness.

Start by attaching the nose cone with a couple of screws and some strong tape to be extra sure as you don’t lose it halfway down the chimney, tie on the rope to the nose cone and drop the other end of the rope down the chimney with some kind of weight on it.

You can either straighten up the liner on the ground and pull it up or bring it up as a coil on to the scaffold and unravel as it goes down.

Once you have the rope down the chimney you can start feeding the liner down the chimney, you will need your helper at the bottom of the flue, pulling the rope.

If you find it gets stuck try twisting the liner in a 360-degree motion while your helper continues to pull so that the liner can find its way around the tight bends.

Once the liner is down, make sure to leave a foot sticking out the top.

Attaching the Pot hanging cowl

Its now time to put on the pot hanging cowl, this fits inside the flue liner and is then held in place by a jubilee clip which you screw on tightly

Leave 12inchs proud and to attach the cowl to the liner before pulling it down and connecting to the chimney pot.

After securing the cowl to the liner push the last foot of the liner down the chimney and use another stainless steel jubilee clip to now attach the cowl to the chimney pot.

Issues around the chimney

Now you have finished the high up sections it is worth checking for any issues up around the chimney and roofline while you have the scaffolding up

 Old ariels not in use can be removed.

 Leadwork hanging out can be repaired.

Chimney pot flaunching should be checked and replaced

The pointing around the chimney stack that’s in need of repair should be raked out and redone.

 As you won’t be going up there again for years to come.

Attaching the stove pipe adapter

knife, tin snips,

Back on the ground, it’s now time to cut off the excess Flexi-liner, remember this can be very sharp, we recommend using cut proof gloves.

I find that the best way to shorten the pipe is to unravel while using cut proof gloves.

The best way we have found is to cut the liner open near the top of the chamber opening with a Stanley knife and then to use snips to detach the excess liner.

You may find that you can’t quite get to the part of the liner you need to cut, this is just above the opening of the chamber, you need to make sure that you leave space for the stove pipe adapter to be fitted out of sight and also so it can be positioned in the middle of the chamber so that the stove pipe when fitted will be straight and centered.

Liner being pulled down with nose cone attachment

The stove pipe adapters we use are either screw on or come with wingnuts so won’t fall off.

Fitting the closure plate

Tools-SDS Drill, angled drill, drill driver,

With the pipe in place, you will feel like the hard bit is over, and it is but that’s not to say the next step will be straightforward.

The closure plate will need to be cut to size so that it fits snugly into the roof of the chamber.

Closure plate fitted for a wood burning stove

When cutting remember to measure the space from the stove spigot to the wall that you need so as not to cut it too close to the wall leaving no gap behind the stove or having a stove pipe that leans forward.

To fit the closure plate you can use the metal angles supplied by fitting these to the wall and then screwing the plate to it using metal self-tapping screws.

Alternatively, use a concrete board (not a plasterboard). Fermacell h20 board is recommended.

Depending on the look you are going for this can look really good sprayed black as it blends in a lot more than a shiny silver closure plate.

Closure plate fitting

Once the closure plate is in place, you can now think about putting the stove into place and connecting the stove pipe.

Insulating a chimney

We don’t often recommend doing this unless there have been issues in the past with the Chimney draw.

Just by adding a liner you will find this helps the draw considerably, insulating with vermiculite or wrapping in a heat resistant liner blanket won’t do any harm though as it will make your liner warmer which will only help with the chimney draw.

If you live in an extremely cold place with an external chimney than this might be the right option for you.

One issue that can arise is that the vermiculite can create damp as the airflow is reduced, meaning in some case damp can start to penetrate into your home.

Fitting the Stove

To fit the stove you will need- Sliders (basically some kind of protection to stop the stove feet scratching the hearth), an angle grinder with ultra-thin cutting disks. Sack truck.

Salt fire stove in Place

Materials: Stovepipe, (with soot door if there is no access through the stove, 15 or 45-degree elbow, fire cement, fire rope or flexible high temp sealant.

The first job is to measure the distance between the stove and the stove pipe adaptor, this is the measurement that you want to cut the stove pipe, make sure not to cut it too short,

I always add an extra 1 inches for a nice tight fit, this can make it harder to get into the stove but better than having a too short pipe, you can always cut more off but you can’t add any on.

Slide in the stove while pushing up the pipe before letting the pipe sit in the spigot

With this method, you also need two people, one to move the stove and 1 to push up the stove pipe up (there is normally a little bit of a spring).

A good way to make this easier is to use one of our extendable pipes or an extended pipe adaptor, this way you know you will have enough pipe length and not have to use a crowbar to leverage it into place which could damage the stove.

Slide the stove or if possible lift the stove into position.

Be careful of your back!

Before inserting the stove pipe into the stove spread some fire cement around the base of the stove spigot.

Once the pipe is in place be sure to tighten up the clip once extended and use high temp flexible sealant to fully seal the top of the stove, as well as any, joins in the pipe.

Fire cement has a tendency to crack over time and this is why the high temp sealant is such a good idea due to its ability to stay flexible and it can look neater.

Polish the stove and hearth once all sealed up

Finish up the sealant around the top of the pipe where it meets the closure plate, as well as around the edge of the closure plate to stop any debris falling down onto your new stove.

Fit a Co alarm

This should always be your step one it’s the most important, as it saves lives. CO is a smell-less gas that needs to be taken seriously. If you didn’t do it as step one do it now!

Finally, the notice plate needs to be completed by the installer.