Currently the housing sector accounts for about 40 percent of societies total energy consumption. New methods of constructing houses can greatly reduce the use of energy for modern homes but measures must also be taken to make existing buildings more energy effective. One method of doing so is by so called weather optimization of the buildings heating system. This means that the level of heating is based on detailed information about the weather instead of solely the temperature, which is the case for the majority of buildings today.  The aim of this report is to evaluate these systems from a real estate owner perspective. This is done by studying a commercially available system and a locally developed system for weather optimization in order to evaluate how they operate, their benefits and the level of competence needed to implement them.