Thermal energy storage incorporated into the fabric of buildings provides the opportunity to significantly reduce the energy load of those buildings, improve the use of energy from renewable sources and take maximum advantage of off-peak electricity tariffs. If this kind of thermal storage is integrated into the structure of the building itself, the internal space of the building is not compromised. In this paper, the authors present a taxonomy of currently available fabric-integrated thermal energy storage solutions based on a review of existing literature. The aim of this study is to map the range of extant design solutions for fabric-integrated thermal storage in buildings and detect any omissions in this range of designs. The taxonomy presented in this paper takes into consideration the interaction between the storage of thermal energy and the thermal zones of buildings, the methods and medium used to store thermal energy, and the storage temperature. Also considered here are the different architectural integration options, which the authors present through a catalogue of possible thermal energy storage locations. This paper argues that an active storage system provides a link for active participation in the energy network. Active storage allows the charge and discharge of the thermal energy stored within such buildings when the energy is available and/or economically valuable. This kind of active participation is not possible with passive storage techniques.