The best wood burning stove for cabins, sheds, tiny homes and small spaces: part one

Whether you have a shed, cabin, summerhouse, caravan, shepherds hut or other small space, heating enables you to use the space throughout the winter. I’ll explore the best options out there…

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When you start thinking about using a small space (shed, summerhouse, cabin, tiny home, caravan etc) throughout the year, it becomes obvious that having some way of heating the space will extend and enhance its usability. Heating becomes a necessity if you are living there throughout the winter!

As we’re mainly dealing with off-grid scenarios on this website, you probably won’t have the luxury of enough spare electricity to use that for heating – winter is the time when generating electricity through solar becomes most difficult (low/weak sun, shorter daylight hours and greater chance of cloud), so let’s put electric heating to one side.

My view is that you have three options:

• Diesel heaters (recently, low-cost Chinese-made diesel heaters have flooded the campervan market)
• Gas heaters (propane / LPG)
• Wood burning stove

I don’t have a lot of experience of gas stoves or diesel heaters, so I’m just going to talk about wood burning stoves, and after all, once you have the stove, you can (in theory) be self-reliant on wood as a fuel and resilient to external availability and price fluctuations of LPG/gas or diesel.

In addition, most gas and all diesel still need some 12v electricity for the fans (to blow the heat around) and for safety monitoring, so if your electricity runs out or breaks, so does your heater.

Please bear in mind, these are just my thoughts and opinions, and are based on what was available in the UK in late 2023. I’d love to hear if you agree with me, or if I’ve missed any good options from this article.

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Environmental aspects of wood burning stoves

There’s nothing quite like the feeling you get from sitting in front of a wood burner! From the gentle crackle of the wood as it burns, the gorgeous colour that the flames emit, and that special scent in the air.

But as much as we might romanticise about them, there are also a few downsides that you should at least think about…

A few years ago, wood burning stoves were universally seen as being a good ecological option for heating, especially compared to gas, oil or electricity (generated with fossil fuels). Improvements in the design and efficiency of wood burning stoves over the years have increased their eco-performance (lower smoke and particulate emissions), compared to older models and other methods of burning wood, such as an open fire.

Wood (properly grown, harvested and dried) is a renewable resource. As wood grows, it absorbs CO2, and when burned with the correct moisture content, can reduce your heating related CO2 emissions compared to using gas, oil or other fossil fuels.

On the flip side, wood burning stoves get criticised for what’s known as PM2.5 emissions. PM2.5 refers to a specific size of particulate matter or particles that when released into the air, can affect both outdoor and indoor air quality and in the long term, might affect human health as well as aggravating conditions such as asthma.

The current information on PM2.5 emissions for burning wood (as of 2023, when referring to PM2.5 particulate emissions) as published by the UK government, also includes data from open fires, bonfires, wildfires, pizza ovens, fire pits and BBQ’s within the same category as wood burning stoves, so the evidence is not completely cut and dried.

Keeping a small wood burner going through the night

One of the downsides to smaller, low output wood burning is that the firebox is quite small, which means they need to be fed with fuel more often than a larger, higher output stove. So you might also need to chop or buy your wood as smaller (shorter) pieces so they can fit.

Keeping a small wood burner going through the night can be a challenge. I remember an acquaintance who lived full time in a yurt mentioning that they’d have to get up at 4 or 5 in the morning to reload the burner to prevent things from freezing inside the yurt! That said, yurts are neither highly insulated nor very air tight, so a properly insulated space should hold onto the heat for longer!

When choosing a wood burner, check out the air flow controls – the better and finer control you have over airflow, the better the chance you’ll have to regulate (slow down) the burn rate to make the burner ‘tick over’ and keep some heat coming out for as long as possible.

Always speak to the manufacturer and get their advice for your situation, or find someone who has had one for a while and ask them.

Choosing the right heat output for your space

Wood burning stoves all have a output rated in KW (kilowatt). If the output from your stove is too low, then it might not be able to adequately heat your space, but conversely, if it’s too high, you can quickly overheat a space.

Manufacturers give you guidelines on the ideal space for each stove (which will vary depending on whether it’s for primary heat or just a top up), but these should be treated just as guides only – the amount of insulation and air tightness of your space will have a huge impact too.

Anevay Stoves say “You need 1kW of heat, for every 14 cubic meters, to raise the temperature 20 degrees above ambient in a reasonably insulated space.” They also have a handy calculator on their website – just type in the width, height and depth of your space in metres, and it will tell you how many KW of heat you need:

https://anevaystoves.com/blogs/news/how-to-choose-the-correct-stove-for-my-space

You need 1kW of heat, for every 14 cubic meters, to raise the temperature 20 degrees above ambient in a reasonably insulated space.

Anevay stoves

Installation and certification

Hopefully, it’s obvious that wood burners, together with their flues, get very hot. In a small space you need to think safety when installing a wood burner due to the fire risk. I’m not going to cover the installation, because I’m not qualified to – at some point, I’ll write a blog post covering my own installation, but do seek advice to ensure you eliminate fire risks with heat shields, non-combustible materials, space and vigilance.

Get a Carbon Monoxide alarm and install it correctly – wood burners produce carbon monoxide. And don’t forget that burning wood consumes oxygen, so ensure there is a good flow of fresh air to enable the fire to burn well at all times.

Always use an insulated flue, especially where it passes through walls or ceiling – as well as being safer, they improve the draw (updraft) and enable the stove to perform more efficiently and with lower emissions. By the way, insulated flues are not cheap, so you’ll need to factor this in.

When you install a wood burner in a permanent dwelling, the installation of the burner and the flue must be either signed off by a building control official (see your local council) or be installed by a ‘competent’ person, which is reality means a HETAS certified engineer. Installations have to comply with part J of UK building regulations.

Installations in narrowboats have to be approved by a boat safety inspector to get your boat safety certificate issued/renewed. For other places (cabins, sheds, yurts, camper vans, vans, caravans etc), there’s no official inspection or certification, but remember you are responsible for your own safety and of those with you in that space.

Any new installation that requires certification will need a CE approved stove .

What to burn?

For wood to burn efficiently, it must be seasoned or dried. The moisture content should be under 20% otherwise, your burn will be a) inefficient b) potentially increase the soot deposits in your chimney and c) emit more smoke and pollution.

To get wood to that moisture level the wood must either be seasoned or kiln dried. I have a bit of an issue with kiln drying on the basis that you are using one form of energy to dry wood so you can burn it, so it’s like using double the energy! However, I’ve been told that many kilns run off ‘waste wood’, which I guess is better, but it still seems wasteful to me.

The Woodshack have a nice blog post about moisture levels in wood and how to check if it’s really dry enough to burn efficiently: https://www.the-woodshack.co.uk/blog/moisture-content-of-firewood-explained

There are lots of arguments and folktales and myths about the best wood to burn – have a search online for some ideas, but Ash, Oak, Cherry, Hawthorn and Yew are all good choice. Conversely, there are certain woods to avoid, such as Eucalyptus, Larch, and Firs due to their high sap content which can cause excessive deposits in your flue.

A relatively new development is ‘heat logs’. Made from compressed sawdust, they are regularised and commercially produced to a standard. There are many types available so it’s best to get a personal recommendation, but take a look at Lekto Wood Fuels to get a taster.

Finally, do consider the size of your wood! Regular woodstoves can take logs of up to 25cm long, but smaller stoves can’t fit that size wood. My own Glastonbury Burners stove prefers logs just over 15cm long. I’ve recently found a company in the UK called Love-Logs and they sell “Hobbit Logs” by mail order in either 20cm or 15cm lengths – they also claim to be ‘plastic free’ which is great.

In part two, I’ll be looking at some models available on the UK market, and make some recommendations – stay tuned!