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Just as pallets are incredibly useful, so too is 'pallet wrap' - a very thin, transparent and incredibly strong plastic film supplied on rolls which is both stretchy and self adhesive. Other than a pallet itself - surely there is no other product with such useful qualities? The number of possible uses is endless, but helping stack firewood must be somewhere near the top of the list.

Why do we need pallet wrap and why do we need to stack firewood at all?

First of all, firewood needs to be stored somewhere dry, preferably for about 2 years, so that most of the moisture within the wood is evaporated or else much of the precious carbon energy locked in the wood is wasted by evaporating large quantities of water in the fire itself. Check out 'The latent heat of evaporation of water'.

Secondly, stacking wood saves space and thirdly, pallet wrap stops our stack from collapsing and provides extra heat from the 'Greenhouse' effect of using translucent film.

We could just throw our precious logs onto the ground and cover them with a tarpaulin, but this has many problems:

  1. The logs in contact with the soil will stay damp
  2. It takes up a lot of space
  3. Tarpaulins are expensive
  4. There won't be much ventilation for the logs to dry effectively

I stack my logs on pallets to keep them off the ground and help with ventilation - some air can circulate under the log stack. I also create special vents in the pallet wrap to help evaporate the water..

But let's just go back in time a bit to last year when I wanted to stack my firewood on a pallet to dry. The middle of Summer is the best time to do this job as it gives the wood, which was cut the previous winter, enough time to dry for the forthcoming winters.

So, I was dutifully stacking my wood thinking what a nice pleasant and easy job it was and after getting to about 1 metre (3 feet) high ........ One of the corners of the stack spontaneously collapsed and I literally had to rebuild the whole thing from scratch - DOH!

Stacking wood is a lot easier against a wall or in a shed where you have upright surfaces to lean it against, but my stacks need to be free standing like in the photo above. Anyway, after rebuilding the structure 3 more times, I realised that I had to give the whole task a great deal more thought and consideration before the next build.

Step 1: How It Works

The log stack is ventilated by a combination of natural ambient wind and hot air convection currents induced by the 'Greenhouse Effect' within the stack.

When the sun is shining, convection currents occur as expanding hot air requires an escape route. If the sun is in the west, then the west facing sides of the stack get warm - up to 40 degrees C so far. The hot air expands and rises and this movement sets up a circular current inside the stack which results in air moving downwards on the colder East side of the stack and out of the vents.

The simulation above assumes that the wind and sunshine is coming from the same direction. The air comes in from the vents and under the pallet on the left hand side and rises up into the top of the stack by convection currents and comes down again and out of the vents again. The graphs at the 'Graphs' step confirm that air is moving fairly freely, even deep within the stack, by showing constant temperature and humidity changes on the probe located therein.

If the humidity in the centre of the stack was a constant 100% and the temperature never changed much, then the conclusion would be that there was no air circulation and inevitably our logs would turn to compost.

<p>I can see that you've mastered your technique. But what is the benifit over just creating a crate of pallets and wrapping that, it seems like it would be much easier. Also could you improve ventalation by trapping short lengths of hose or drainpipe between the layers of wrap?</p>
<p>Just a shortage of pallets I suppose! I like your ideas, thanks!</p>
<p>excellent write up as usual. You got my votes.</p>
<p>Nice instructable! I've been doing the same for many years, but I wrapped mine for stability when moving the pallets via skid steer. In doing so, I found I have to handle the wood one less time when using skids. I like your description of the science of the solar effect of seasoning the wood. Very thorough, good job.</p>
<p>Excelletn! Did you make vents for drying?</p>
Never found to be an issue. The top wasn't sealed up during the hot months and covered with a tarp during the winter before use. The rain &quot;passed through&quot; so to speak. My wood was mostly oak and required a lot of ventilation to season, and I remove as much bark as I can. I find the bark is a breeding ground for insects and rot and retains most of the moisture. <br>
<p>Oak is a nice wood for an airtight but should be mixed with some other hard wood, (Maple,iron wood, beech, etc) as oak burns very hot and also much quicker than other hardwoods due to it being a very low density wood. I use oak in my wood furnace that heats my entire house (Continental Hybrid 150) but I always ensure to add other hardwood types in the mix.. </p>
<p>False assumption about wasted energy heating water in the wood. So long as the wood is dry enough to burn at a rate you find acceptable, the heated water coming off heats you just as well as if the wood were dryer. It is still heat, not wasted at all.</p>
<p>It takes exactly 1 BTU to convert each pound of water to steam (it is the fact that the BTU unit is based on). That BTU is absorbed in the process and does NOT produce any heat. Weigh a piece of green wood and compare it to its weight after a year of drying - you'll be amazed at the difference. Even &quot;almost dry&quot; wood loses a lot compared to completely dry.</p>
<p>You can do a simple science experiment to find the facts about this. </p><p>Get some large cardboard boxes and run them through a shredder. (I shred cardboard all the time so a regular paper shredder with a 12 sheet capacity can do this). Using a scale divide up the cardboard into three piles. One pile is your control. It should be dry and free of any contamination. To the second pile add a measured amount of water and keep it in a plastic bag so the water gets dispersed evenly. After a day the cardboard should be damp but not wet. To the third pile add a lot of water, but not enough so that it will not burn. </p><p>Now the hard part, get some instruments that can measure the amount of energy given off when the cardboard burns. Some of the others might have some good suggestions here as to what to use. </p><p>Finally burn each pile and calculate how much energy each produces. They all three have the same energy content to start with. What conclusion can you draw from your results?</p><p>This would be a fun science fair project. </p>
<p>Thanks for your comment ac. I still believe that burning wet wood causes the heat to be lost. It's the 'latent' (which means 'lost') heat of evaporation, which effectively disappears and is no use to use unless it condenses back into water again. If the water trapped in the log was a gas then you would be correct, but it's all about the heat lost in the phase change from liquid to gas and water has a particularly high value.</p>
<p>You present a non issue while make a false assumption about the physically held water. The energy to heat the water in properly stacked and dried wood is negligible but in poorly seasoned wood it can require so much energy that combustion cannot be supported. As to the heat of the steam/water vapor it is lost to its rise up the chimney or the atmosphere in an open fire, Contrary to popular belief heated air is of little use to most heating fires because of its immediate rise although there are a number of ways to utilise this often wasted heat and these would be excellent subjects for instructables. The real heating is done by infrared radiation.</p><p>However the problem with physically held water in wood is that the relatively low combustion temperatures burn less of the combustible gasses released by the heat of the fire and these unburned gasses combine with the water to form creosote which is deposited on the inner surface of the chimney creating a serious fire hazard. </p><p>Stacking cordwood against the side of a wooden structure is not recommended because this can be an invitation to termites and carpenter ants.</p>
Also, as you can see by the third skid, my dogs found a chimp ink had moved in and assisted with the ventilation process by ripping off most of the wrap!
<p>Is your assistant Azealia Banks?</p>
<p>Yes - we were working on a new song together and did the log stacking in our lunch break.</p>
<p>! </p>
<p> I just thought of a fantastic user name, thanks to a phrase from you:</p><p>Chuck Random</p>
<p>And he could have a brother:</p><p>Phil Random</p>
<p>Would they perhaps work for the Bill Random Collection Agency?</p>
<p>I should get a hat like that for my assistant.</p><p>But then I suppose I should get an assistant first. </p><p>&quot;Help Wanted ---- special assistant to Phil Hat, cousin of Phil Random. Must be good at wrapping things up.&quot;</p><p>I'm sorry. I must be in a punny mood today.</p><p>I have been cutting logs all week now. I have had 6 flat bed trailers of trees dropped off last week. A friend is helping to clear trees out for a new fence on a property by a golf course. They have been yanking them out of the ground with a front end loader and stacking them on the trailer root ball and all. It's a big mess now. Kind of like a giant was weeding his garden. But some of it is really good wood, and free is always a good price. </p>
That's cool! What species of wood did you get? ..... And whilst in the mood for puns ..... The 'burning' question is ..... Are you going to wrap your logs in pallet wrap?
Otherwise your wood will rot before it can be used<br>
<p>I've changed the title adding the word 'ventilate' to make it more obvious what's going on here. Thank you.</p>
It is important that air can enter at the bottom of the stack and moisture and air can escape at the top
<p>Yes - there is ventilation at the bottom within the pallet structure and the pallet wrap is pulled away from the sides to create rain proof louvre vents. There is no condensation in the top section so the vents do seem to be working well.</p>
<p>I use old pallets to keep the firewood from touching the ground. I have a large, open roofed area so just pile the wood on the pallets and use lengths of rebar mesh to keep the wood from spilling out.</p><p>Make sure there is lots of ventilation and that the air can get out the top. Otherwise, you will end up with piles of compost.</p>
<p>The logs seem to be drying out very well although some compost would be useful too!</p>

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