Humidity sensor alternative ?

[lpatiny]

http://www.kandrsmith.org/RJS/Misc/Hygrometers/calib_many.html

[cmdoret]

@oliemery suggested https://learn.sparkfun.com/tutorials/si7021-humidity-and-temperature-sensor-hookup-guide
The library looks smaller than for DHT22:
https://github.com/sparkfun/Si7021_Breakout/tree/master/Libraries/Arduino/Si7021/src/SparkFun_Si7021_Breakout_Library.cpp