A window is an opening formed in a wall or roof primarily to admit daylight through some transparent or translucent material. Windows also serve an important function in providing controlled natural ventilation to buildings and make a major contribution to the visual appearance of buildings. As the window is part of the wall or roof envelope, it should serve to exclude wind and rain, and act as a barrier to excessive transfer of heat, sound and spread of fire in much the same way that the surrounding wall or roof does.
7.1 Functional requirements
The primary function of a window is to:
- Admit daylight and provide a view
Additional performance requirements include:
- Safety – comply with relevant health and safety legislation, including the Construction Design and Management (CDM) Regulations
- Strength, stability and airtightness
- Fire safety
- Provision of ventilation
- Resistance to the passage of heat
- Resistance to the passage of sound
- Durability and freedom from maintenance
The key elements of a window within a typical wall detail are shown in Figure 7.1.
The prime function of a window is to admit adequate daylight for the efficient performance of daytime activities. The quantity of light admitted depends in general terms on the size of ...