1. Identify and measure the main sources of heat loss

1.1 Identify losses

Energy loss refers to the loss of energy produced, while heat loss is the loss of heat that a building experiences through its walls and fluid exchanges with the outside. This study will be based entirely on heat loss, which generally occurs in three different ways:

• loss through surface walls;

• heat loss through thermal bridges;

• finally, loss through air renewal and possible leaks.

These losses are even greater when thermal insulation is poor or non-existent.