Abstract: A fenestration unit controller can be used to control automated opening or closing of fenestration units such as windows. The controller can be configured to receive an environment comfort target characteristic for an indoor environment. The indoor environment can include a fenestration unit that can be remotely controlled. The controller can be configured to receive atmospheric status information about the outdoor environment, and information about a solar loading offset for the indoor environment. The controller can determine a difference between the atmospheric status information and the environment comfort target characteristic. The controller can control the fenestration unit, such as to open or close the unit, based on the solar loading offset for the indoor environment and on the determined difference between the atmospheric status information and the environment comfort target characteristic.