Heat loss is the phenomenon in which thermal energy flows from a warmer space to a colder space due to a temperature difference. This process is a natural physical law that is present in all buildings and rooms, but can be reduced with appropriate measures.
How does heat loss occur?
The main cause of heat loss is heat flow, which can occur in three ways:
Conduction: The movement of heat through solid materials, such as walls, floors, and windows.
Example: Through a poorly insulated wall, internal heat energy flows into the colder outside space.
Heat flow (convection): Heat transfer by the movement of air.
Example: Cold air flows in through leaky windows or doors while warm air is displaced.
Thermal radiation: The emission of energy in the form of infrared radiation.
Example: Warm indoor thermal energy radiates through a window into the colder outdoor space.
Factors affecting heat loss
Building structure: The quality of the insulation, the thermal conductivity properties of the materials and the condition of the windows and doors are decisive.
Building size and shape: Larger buildings generally have higher heat losses, but shape is also important: a compact, rectangular building will suffer less heat loss than a protruding structure.
Doors and windows: Windows and doors that do not close properly can cause a significant amount of heat loss.
External temperature: The greater the temperature difference between the interior and exterior, the greater the heat loss.
Wind and location: Windy environments and building location can increase heat loss, especially for buildings on corners or in open spaces.
Example of heat loss
In the case of a single-family house:
- Heat loss through walls: 35%
- Heat loss through windows: 25%
- Roof heat loss: 20%
- Floor heat loss: 15%
- Door heat loss: 5%
In a poorly insulated house, heat loss significantly increases heating costs, while in a well-insulated house, this loss can be minimized.
Summary
Heat loss is a natural but preventable phenomenon that affects the energy performance and costs of any building. Proper insulation techniques, energy-saving systems and airtightness measures can significantly reduce losses, thus not only saving money but also contributing to environmental protection and sustainable building design.