By having an enclosure around the pool it means you have to clean your pool out less. This is due to the fact that with the use of an enclosure you can stop the flies, leaves, and other debris falling into the pool.
Also by having an enclosure for swimming pool you can reduce the evaporation, which means the cost of chemicals is reduced and the level of your pool water remains even more.
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Evaporation is one of the biggest causes of heat loss when it comes to your swimming pool. When your pool is covered, the heat is trapped which cuts down the cost of heating your pool.
An enclosure will also mean that you do not have to worry about the temperature reduction during the night even on the coldest night of your swimming pool will still be warm.
This is because in the daytime enclosure absorbs heat and reflects into your pool water where it remained; this can increase the temperature as much as five degrees.
What I am basically saying is they are worth the investment because they will save money and allow you to use the pool again and extend the life of your pool.