Passive heating is crucial and desirable in many cold climates and in mild climates in winter time to ensure that thermal comfort is provided with minimal energy use, energy costs and CO2 emissions. This can be provided by capturing the sun’s warmth by good passive solar design (i.e. optimising orientation and window locations) and ensuring that the heat is stored in a well-insulated envelope with good use of thermal mass and passive summer-time cooling strategies to avoid building overheating. Passive heating strategies need to be ‘locked in’ at early stages because it is irreversible over the building’s lifespan.

Good natural light, views and connection to outside are crucial for human health and well-being. Good visual comfort needs to be provided in all spaces inhabited by humans for any length of time. Doing so supports people’s well-being and can create delightful spaces, while at the same time minimising the energy needed for active heating and artificial lighting. This can reduce running costs and reduces running costs and tackles the climate emergency.