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I Does insulation protect outdoor objects from cold

  1. Mar 18, 2016 #1
    I have an object ( a windsurfer board) which I want to protect it from the cold but I cannot store it inside.
    The outside temperature now is a few degrees above 0 Celsius during the day, but is expected to drop to -8 at night for the next few days..
    Assuming that during the day the board will have warmed up a little, maybe to above 0, am I right in thinking that putting insulation around it as much as possible will keep its temperature above 0 Celsius even if the outside air temperature at night falls to -8 C ? Are my assumptions wrong? All I want is to keep it around 0 degrees C or a few more days, until more seasonal spring temperatures kick in. .

    Thanks for the input

  2. jcsd
  3. Mar 18, 2016 #2

    Simon Bridge

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    The answer is "it depends" ... some insulation is better than others and I don't know what "as much as possible" means.
    It also depends on what sort of damage you want to protect the board from ... what happens to it at low temperatures?
    But: there is no insulation that will allow the temperature to remain constant.

    If I had to bet on it without seeing what you had in mind I'd say "no": the board will go sub-zero overnight.
    Have you tried asking on a windsurfing forum: this is the sort fo thing people learn from experience and pass on.
  4. Mar 18, 2016 #3
    The danger which is looming , however perhaps somewhat remotely,is the one of delamination. A board is made of a few layers of materials like fiberglas and various types of special plastics glued together.

    Although windsurfing boards today are high- tech and very resilient , delamination can sometimes occur, but mostly the culprit is heat, not cold : in tropical areas, boards are sometimes inadvertently left for prolonged periods of time under the baking sun, which causes expansion of the material, hence, beyond a certain point, delamination, especially if there is no vent plug or the plug is left closed.

    Most of the windsurfers I asked don't see any danger in storing boards in non heated areas, even outside, but for some reasons Bic ( the manufacturer) has a warning sticker on the package not to store it at 0 degrees C.
    I tend to believe that Bic intends to warn not so much against storing in the cold per se, but against the possibility of water freezing inside the board and therefore taking expansion. There are always small amounts of water getting trapped in certain areas of the board, like the centerboard casing, constantly flushed by water and also the screw recesses of the foot-straps. This is a real possibility in cold climates, like the Scandinavian countries, where people are used to windsurf as early as early spring with air temperatures which may drop very quickly to 0 C at night, from around 10 C during the day.

    Also, being of a somewhat curious nature, I wanted to see the issue from the standpoint of physics.

    Thanks for your input

  5. Mar 19, 2016 #4

    Simon Bridge

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    Well all right - standard advise is to store according to the manufacturer's instructions. That's more a liability issue than a physical one.
    From a physics standpoint - insulation slows the rate of heat transfer.

    It's like Ohm's law for electricity. V=IR
    In this case, heat is like charge, so heat transfer rate is the current.
    The voltage is the temperature difference (board temp minus air temp in your case)
    The board is a store of charge inside the insulator which is the resistor.
    A good insulator is like a really big resistor - you can't stop the board losing heat but you can keep the temperature up by selecting a big enough resistor.

    In the case of clothing - you can stay warm because your body generates heat ... so long as you generate heat at the same rate as you lose it, you stay warm. So you adjust your clothing to compensate. But you will notice that staying all night in -8C weather, you are probably not going to be in good shape with serious protection. Remember, that is with an internal heater. Without that heater - the cool-down is much faster.

    The rest is material properties: which is very complicated.
    Off experience: housing insulation around the board will probably not be enough to keep it above zero all night ... you'll notice that the house gets cold, even with the insulation, if you don't heat it. I suppose you could try wrapping it in pipe lagging and put it in a big box with foam packing beads, then wrap the box in polystyrene sheets... but wrapping in a duvet with a heater inside (say, wire wrapped about and powered by a car battery)?
  6. Mar 20, 2016 #5


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    Wrapping a surfboard in insulation will reduce the temperature swings that it sees but after awhile these swings will be centred on the average air temperature. If the air temperature was say +2C for 12 hours and -8 for the other 12 hours then the average would be around -3C which is on the low side. Some form of heating might be required.

    Got anything that you could fill with warm water each night? Perhaps an air bed?
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