What is the correct way to place my pool blanket?

Pool blankets, or bubble covers, can be a great way to heat your pool in the summertime, and they are also excellent at reducing evaporation.  Heating a pool can be a very costly endeavor if you are relying on an external pool heater to make your pool a comfortable temperature.  Even using solar panels can get expensive if you need to run your pool pump at peak hours to circulate the water through the solar panels.  And with the drought in and cost of water, evaporation in the summer can result in the loss of a few inches of water every week.  This translates into hundreds of gallons of water lost into thin air and your water bill going up substantially.

Pool blankets are cost effective and practical

A cheap and easy solution for these problems is a pool blanket.  For as little as $100 depending on the size of your pool, a pool blanket can heat the pool with the energy of the sun (which is still free) and practically eliminate evaporation.  And even if your pool is not rectangular, installation can be very simple because you can purchase pool blankets in a variety of sizes.  Usually the critical dimension when selecting a pool blanket is the pool’s width.  You should try to find a pool blanket with a width that is as close as possible to your pool’s width.  That will reduce the excess material when fitting a pool blanket to your pool’s dimensions.  For kidney shaped pools it’s possible to cut your pool blanket to fit exactly, but then you won’t be able to use a roller for storage.  Retaining the rectangular shape and letting the pool blanket overlap onto the pool deck a little bit is much more practical.

So bubbles up or down when the pool blanket is on the pool?

Pool blankets, or bubble covers, heat the pool by transferring the heat trapped in the air in the bubbles to the pool water.  By placing the bubble side down on your pool blanket, you will immerse the bubbles in your pool blanket in your pool water, and they will be in direct contact with the surrounding pool water.  So the heat transfer will happen through conduction.  If the pool blanket is placed with the bubbles facing up, then they will only be heating the air around them.  While you will be preventing evaporation of the pool water, you will not be heating the pool as effectively as possible, if at all.  So the correct answer is the bubble side of a pool blanket must always face DOWN.