What is the evaporation rate of an outdoor pool in Florida?
Evaporation rates vary depending on many factors such as relative
humidity, air temp, water temp, and wind speed. Also running water
features such as spitters, water falls, sheer decents greatly
increase the surface area of water increasing the amount of
evaporation. The swimming pool construction company I work for
considers 1/8 in. water loss per day normal evaporation. Pools that
run multiple water features for extended periods of time may lose
upwards of 1/4 in. per day.
The evaporation rates of occupied and unoccupied swimming pools
have been measured to derive empirical equations for calculating
loss. Three references are:
1. Smith, Charles C., George O.C. Lof, Randy W. Jones, "Rates of
Evaporation from Swimming Pools in Active Use", ASHRAE
Transactions, Volume 104, 1998
2. Smith, Charles C., George O.C. Lof, Randy W. Jones,
"Measurement and Analysis of Evaporation from an Inactive Outdoor
Swimming Pool", Solar Energy, Vol. 53, No. 1, pp. 3-7, 1994
3. Shah, Mohammed, "Calculating Evaporation Rates from Indoor
Water Pools", HPAC Engineering, March 2004
A spreadsheet tool for estimating the heat loss due to
evaporation from an indoor pool is available at
This tool is based on the reference above by Shah.