This manifesto, at the interface of architecture, aesthetics and engineering, calls for a return to the practical uses of interior decoration that were widespread before the 20th century. In the wake of fossil fuel–driven modernity, the efficiency of heating and air conditioning eclipsed the indoor climate–regulating functions of carpets, tapestries, curtains, mirrors and folding screens, relegating them to merely symbolic or aesthetic roles. However, given the urgent need in the Anthropocene epoch to reduce our energy consumption and CO2 emissions and stave off increasingly frequent and intense heat waves, we would be well advised to take advantage of the thermal value of decorative art again and reboot interior design, the spatial, formal and material configurations of our homes, with a view to optimizing climate-regulating performance. We call this 21st century functional and decorative aesthetic ‘the Anthropocene Style’.