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…and right soon. So let’s think about heating options. Despite humanity’s best attempts to turn the Earth into Venus 2.0, we aren’t quite there yet. In higher latitudes, some kind of dealing with cold will be necessary. There are several options, all with benefit and bale.
You can do what mother says and put on another sweater. That is, passive options for dealing with cold weather are certainly primo. Literally sweaters, natch. But the caravan camper can also take some attention to insulation around this time of year.
Styrofoam is beastly stuff, ecologically. But it does cut well by hot wire to fit unused windows. There are silver foil window reflectors which are made for hot climes, but work just as well for Windows, too. Find those at home supply stores. Face those outside and inside, with styrofoam, old flannel, trash bags… any such matter, really. The foil window insulators will dress the window tidily. With some curtains, this sandwich will keep for any camper or cabin a bit more snug.
Consider also passive heating options. One doesn’t want a dark exterior in summer, of course. But as the Sun bumbles down in the sky through fall, painting the bottom of one’s camper a darker colour helps speed morning warmth along. Think about which faces hit the sunlight at which times of the year, wherever you camp. Minimize sunlight exposure in summer with awnings and shady trees. Maximize exposure in winter by facing the long side toward the equator.
If push comes to shove and one can’t take the cold, follow the snowbirds. Humans were meant to be nomads from deepest antiquity. A warmer climate in winter allows less worry and needs less preparation.
But let’s say you want to play with fire.
It’s common in North America for campers to be fitted with propane tanks for cooking. These can also do to fuel a catalytic heater. If you’ve not seen them, here’s how they work. The propane seeps across a ceramic wool mesh. A spark from a fire starter button or match sets it to glow, essentially as a large gaseous lantern wick. But the burn is slow and low, producing more heat than light.
Catalytic heaters certainly are pleasant. Their warm, orange, gently shifting glow betokens the domestic comforts of Yuletide. Provided their fuel line is well sealed, they burn cleanly. They are easy to start and to handle. For quick heat, there’s no equal. This could literally be a lifesaver.
Propane does have a few downsides to consider.
First, propane is refined from coal gas, so-called natural gas. Fracking isn’t as clean for the health of Mother Earth in generation as it is when expended.
Burning propane uses ambient oxygen, so does require one to keep roof vents open and a few windows cracked. Suffocation would ruin that cosy winter cheer. And that propane does go rather quickly. Much more quickly than with stove use alone, requiring
Propane also produces water vapour. Heaps! And water means chill. This might be a feature for those who need or prefer a moist air. But as nights chill, this water will condense on surfaces into an unseemly dew. When one turns the heat off and the room chills, it will only make you shiver all the more, and spoil any loose tea leaves.
But let’s say you’re truly an intrepid nutter, I mean, eccentric nonconformist. You shall put a wood stove in a camper. They will say you’re gonzo. As far as regulations go in any country I’ve checked, putting a wood stove in a caravan truly will put you far off grid. That said, one needn’t be reckless even if one is novel. There are many ways to mitigate the dangers of burning wood for heat. I’ll outline my methods of construction in hopes it stirs ideas.
First and foremost, really do consider the safety implications. Read your local home wood stove installation code to get a sense of what is recommended to keep buildings safer. You’ll want to follow the code as much as possible, and exceed it when one can. The building code often talks about tolerances: how far a stove or stovepipe or chimney ought be from flammable surfaces. Respect these guidelines! If one can’t achieve them with distance, one will have to mitigate with more insulation or other heat mitigation.
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With the code in mind, consider the actual conditions. Is your camper big enough to accomodate a fire and disperse the heat? Is there space for a stove? Does this space include reasonable code tolerances and added fire insulation? How will the heat plume off a fire move throughout your space? How will you keep heat from puddling behind and above the stove? Will you have to manage the exterior to allow good airflow whilst burning wood? Do you know how to manage a fire to keep it small and slow burning? Now is the time to second guess oneself. Prudence is a virtue.
Let’s say one is plum gazoo and decides one can do it. It just so happened I was thus gazoo. I had a dinette table area which fit the bill. This I removed, and removed the carpet which covered the slightly raised area beneath the dinette table. I was left with a boxy area at the port bow of my mostly fibreglass camper. This area was about 6 feet high, and half as wide and deep. It faced the door. On one side the kitchenette. On the bow side, a bunk bed I used for storage. Tight, but doable.
About this moment in my renovations I started looking for stoves. There are many options, and none of them perfect. House wood stoves are jolly well too heavy and grand. There were a few nice small cabin stoves built by Pennsylvania Amish which I adored. But these too were rather heavy. I was left with boat stoves and tent stoves.
Boat stoves are probably most people’s best bet. They are made for this application. They stand on end, as it were, to minimize floor space, a cylinder with a flat on top. In this design, they are well made for burning coal or a few slender pieces of wood stood on end.
The chief issue with boat stoves in a camper is to remember that they are made for boats, with water cooling the hull nigh the hot bits. That is the assumption with most installations. Even with a boat stove, it thus behooves the adventurer to follow the building code. They are also often quite heavy for their size, I recall.
And boar stoves don’t leave much room on top for kettles or cookware. Their slender profile also requires more feeding of the fire, ad more finicky processing of wood to fit the chamber. Yours truly being lazy ilk who preferred to start and leave more stove fuel with minimal mucking about, I decided to go with a tent stove.
I prefer the look of tent stoves, with their long legs and forward door. They are able to accomodate different size wood in a more traditional fire.
That said… It must be underscored that most tent stoves are pure rubbish. During research I once saw a video online of a chap who installed a very cheap stove to his RV. Said stove was notorious for burning through, as it was basically a repurposed oil drum. We ought to resolve to not go el cheapo with the stove box itself.
To that end, I decided on a well reputed front loading stove made from thicker steel. This added some weight, but was worth the peace of mind. Furthermore, the welds on said stove are the loveliest, cleanest, most sturdy welds I have ever seen on steel. Pride went into the construction of this stove, in pursuit of making it as airtight as possible.
https://fourdog.com/two-dog-stove-dx/
My stove easily fit the area for installation. The first difficult calculation was to find the right arrangement of stove and chimney pipes to safely reach through the roof, which curves gently down into wall. The stove pipe, the black pipes which are uninsulated, had to make a 45 degree turn toward the starboard doorway, across the stove, in order to provide good gap behind them nigh the wall. That is, the flue hole in the stove box was toward the back at port side. The hole through the camper roof had to be above the middle of the stove.
Manufacturers make bits to help with this, wiggly bits which rotate like the segments of a 50’s robot arm to aim several angles around 45°.
However, as much as I liked my stove, its one defect was that it used the 5 inch flue hole diameter. This is common for tent stoves. However, in North America, a 6 inch width is the usual size for house installation materials. There are adapters, but it did add a complication to finding all the right bits to fit.
In the end, I found my bits and arranged them as a stack thusly:
Cute stove pipe hat with spark arrestor -
Removable clamp on chimney pipe section -
Roof -
Metal shielding -
Mounted chimney pipe section -
45 degree adapter -
5 inch to 6 inch flue adapter -
Flue with damper - (dimensions)
Stove - (dimensions)
Stove legs -
Aluminium sheet -
Fire bricks with gaps between -
Wooden platform -
OSB Floor -
^ Chimney hat H Chimney pipe H chimney pipe (bracketed) / stove pipe (45° angle) V stove pipe (6” to 5” adapter) | stove pipe (5” damper) [.] stove A Stove legs = Base board (with bolts through stove feet)
The stack’s bits one is likely to order online. Be careful with mixing manufacturers. For some obtuse reason (cough capitalism cough), some do not fit with other’s wares.
The whole stack I arranged so that I could build the platform underneath the stove to raise or lower a wee smidge as needful. Despite this, I had to cut down the length of stovepipe with metal shears. It’s no fun to cut, and will bite back. But often there is nothing for it but to trim down a longer length of stovepipe.
The chimney pipe fit through a hole cut in the roof, but said hole must by necessity be close in to the pipe but not too close. I recall the code said an inch maybe? There are handy lengths of chimney pipe with attached adjustable brackets to bolt these into any range of likely angles. I used one of these with a high rated asbestos insulation sealed inside.
To keep water out, some high temperature gasketting goop did the trick MUCH better than I thought it would. I built this up between the chimney and roof until it bridged the gap with a flexible membrane of auburn coloured rubber. This stuff is made for engines; better safe than sorry. I thought it would need yearly maintenance, but I’ve not yet had to reapply it. For added rain protection, aerodynamics, and a cleaner look, I mounted an aluminium cone above the roof.
I set this all up temporarily to make sure it fit, only installed the base chimney pipe. Before permanent installation came the shielding. I’m most proud of this design.
The USA building installation code says that if a stove is too close to the wall, one can add metal reflective shielding and insulation. I had enough clearance, I believe, but felt it prudent to go one better on all parameters. So I undertook to make shields for back, sides, below, and even above the stove. Several materials were used.
Above the stove’s length, and then some, and down along the back side of the wall I glued some high temperature automotive insulation. This is the stuff auto geeks put between their engine block and their cab. It has half an inch of ceramic wool insulation on one side and metal reflective material on the other. It might have done the job by itself. Make sure the foil side faces the stove!
Floating above this, I decided to shield the back (port camper wall), the top around the chimney, sides of stove, and below the stove legs with a “floating” aluminium construct I designed myself. The idea was to provide 1-2 inches of cool air behind the shields to flow upward with the floor draft. As I wished to punch as few holes in the camper wall as possible, I contrived armatures made of aluminium bars to secure with several stainless steel bolts to hold the shields “tense” as flat sheets facing the stove. Once these bars held the sheets flat, I could then well secure them with very few stainless bolts to the wall. The armatures would also allow cooling by length of conductivity, rather than bolting shields to wall directly.
The side shields were easy enough. I bolted into the kitchenette side and extended it a bit above the stove, with a gap where circulation let out. Toward the camper bow I built a lightweight stained wood panel to front the bunk the full length of the stove. To the stoveward side I secured shielding. Likewise, the shield on the platform upon which the stove legs were to be attached, I bolted taut atop several fire bricks. The legs were then bolted through the fire bricks, the aluminium in betwixt. This “air sandwich” proved to be cool in all senses of the word.
The rear (camper port) shielding was more tricky, as the wall curved into the roof. I layered large sheets of metal. The largest had to be thin stainless steel, as “aluminum doesn’t come that big” at box outlet stores. Then I layered narrower sheets along the curve, so arranged like scales so that warming air would raise up and flow out to the area which was insulated with the pricey auto insulation.
Because I hate to waste metal, and had one more chimney rain cone, this I set inside at the place where the chimney passed through the aluminium shielding and wall, to help prevent warming of this area.
I had already done an initial fire on the stove. With new stoves, one wants to make a nice hot blaze in them outside when first purchased new. Evidently the paint is quite toxic until so cooked. And how! Nasty vapours rose as it went from shiny to matte. Don’t do that inside. Anyway, it proved a fun bit of show and tell for neighbours. I cooked pancakes and bread on the stovetop and passed them out.
Aside from shielding, one reason I made a platform for the stove to stand upon was the necessity of finagling the stove securely into place. The stove and pipes all had to fit snugly. The best way to do this was to build the base to wedge upwards into the former breakfast niche. Once so wedged, with the large bolts through the floor tightened down, it felt quite secure.
I further used high temperature aluminium stove tape to air tighten all section junctions. I also thought this stuff would need to be replaced regularly, but it has proven durable.
The last bit for the assembly was the removable roof section. I tried to give this at least 3 foot clearance of the roof. Too long, and it becomes too heavy for the roof. Using stove pipe above the roof is a bad idea for airflow reasons. (Don’t cool air above rising from hot insulated air.) This section I kept removable, secured to the bottom with a big hand tightened O ring. This I can remove in summer or when travelling. In those times, a stove pipe end cap, painted and with a gasket, fits into the hole for rain protection.
Now it was time to field test! Thankfully the weather accommodated with some cold.
I ran a series of test fires. First small, just to check air circulation. All good, even though the stove has a full baffle.
Then a “typical burn”. I guesstimated a Swedish fire bed technique with a single small log above would do fine for this size space. If I built it right, a night’s fire would be fueled in one go, if I turned the ingoing dampers down to a quarter and outgoing to 30°. Always smaller or equal throttle in than out! This proved a much pleasing fire, raising ambient room temperatures from about 0° C to about 32° C, then levelling out later in the evening to about 17° C. I had to crack the roof vent a bit, which was an easy way to moderate.
Lastly, I did a “big burn”. Not too big! But a full stove fire as might be expected for a dinner pavilion tent. This was to check for any hot places along the roof and sides of the camper. Similarly, the temperatures outside were about freezing, a tad over. I propped the door open; goodness it got hot! Warm enough for t-shirt and shorts, if not much sweat.
I would periodically check the shields for temperatures. I was shocked to discover just how well everything worked. The shields themselves were cool to touch everywhere but right behind the stove. Outside, I climbed a ladder. The wall was ever cold. Only around the chimney did it get a bit warm eventually. A hot summer day did worse, I think. 40° C tops?
This setup I heartily recommend. Air gaps and shielding. I had considered getting more ceramic wool blankets for behind the stove; but this proved needless.
Hot air rises from the long (deep) stove top and ascends to the roof, where it is radiated by the pool under the auto insulation. The whole circles from from starboard bottom to port top, and along the length of the camper. If it gets warm, shut the inflow dampers then crack the skylight or the door.
I also had a notion to increase entropy, which would hopefully improve airflow through the stove. Instead of having the stove pull air from the warm camper cabin, I built an air intake to the outside. I used an aluminium clothing dryer snake, which discretely hides away in a small bow compartment where I drilled a few vent holes to the floor. To the front end of the snake I attached a few high power magnets within a sleeve of aluminium flashing. I believe it works! Anyway, it’s a fun idea to further air tighten the system.
I pondered wrapping the base stovepipe with copper tubing for a water boiler heat exchange coil. This I wanted to run under my bed as a sort of kang, with the water mass dispersing heat when the fire died down. I’ve not yet gotten to that, and don’t consider it pressing at installation.
Don’t forget the fire extinguisher! Also, it’s a good idea to have an alarm which detects carbon monoxide. Keeping a bucket full of grey water on hand isn’t a bad notion either.
I doubt it would satisfy a Los Angeles fire marshal, but I hope this sketch demonstrates some safer options for winter heating in a caravan.
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