This document provides an overview of behavioural options in the housing sector that aim to reduce demand for space heating energy. It identifies three behavioural change options for further analysis: 1) reducing space heating temperature by lowering room temperatures, 2) optimizing thermostat settings, and 3) optimizing ventilation behavior. The document assesses the theoretical and realistic CO2 mitigation potentials of these options in the EU from 2020 to 2050. It also discusses barriers to behavior change, consumer segments, and policy instruments that could help induce changes in heating-related behaviors and consumption patterns.