Houses with ample windows will seldom look gloomy or feel stuffy. You might feel that windows are nothing more than traditional requirements that each house must have. But, this is not true. Increasingly, homeowners are recognizing the immense value of their windows. In particular, they are becoming aware of how their windows exert a significant influence in the overall look of their homes.
Offer Convenience: The windows in your kitchens permit the escape of hot air. In bathrooms, they facilitate the escape of steam. In other areas of the house, windows enable you to pass messages to people outside the house, without having to venture outdoors. While simple, these things are important in any house.
Protection against the weather: The requirements concerning mechanical stress, joint permeability and resistance to heavy rain. The joint permeability means there is a leakage through the window and frame and is defined by the joint permeability coefficient. The coefficient describes the airflow, which is exchanged between the interior and exterior per meter joint length at a reference barometric pressure difference. The requirements towards heavy rain demands that no water enters the interior when simultaneously exposed to rain and wind.
Daylight: A sufficient level of daylight reduces the energy demand and also provides visual comfort to the homeowner. To guarantee a sufficient level of daylight, the windows have to meet minimal requirements in size and orientation. Further parameters of influence are the room geometry and the surrounding buildings. Energetic disadvantages have to be omitted when optimizing a buildings day lighting potential by enlargement of the glazing area. The energy savings due to reduced amount of electrical lighting and possibly solar gains have to be weight against the increased transmission loss.
Ventilation: Windows are used for natural ventilation of rooms. They have to provide sufficient controlled air exchange and have minimize the infiltration and exfiltration caused by uncontrolled air exchange.
Usage of Solar Energy: In minimizing the heating energy demand of buildings windows can play an important role in optimizing the passive solar gains. A positive energy balance, such as higher passive solar gains than transmission heat losses, is only accomplished by windows with low u-values and high solar heat gain coefficients. An ideally oriented building and suitable designed shading devices are necessary condition to accomplish this goal. South oriented windows are preferable. The energy input into the building with this orientation is smaller compared to east or west orientated windows and is easily controllable by simple shading devices, because in summer the incident angle of the solar radiation is very high. Whereas in the winter, the low standing sun maximizes the solar energy gain and reduces therefore the heat energy demand of the building.
Sound Insulation: Noise imposes a health risk for human beings. Long term exposure greatly increases the risk for heart and circulatory diseases. To protect humans from external noises, windows have to fulfill requirements concerning airborne sound insulation. Parameters influencing the sound insulation properties of a window pane and frame itself, and on the other side the airtight construction of the seal of the casement and the joints. The sound insulation of the glazing increases with increasing thickness, damping capacity of the space between the panes, and the number of panes.
Thermal Insulation: Heat transmission and airtightness characterize the thermal insulation qualities of a window during winter. The heat transmission is defined by the overall heat transmission coefficient which again is defined by the heat transmission coefficients of the glass, the frame, and the length related heat transmission coefficient.
Security: security is divided into active and passive measures for windows. Passive security deals with the protections of individuals during the usage of windows such as opening, closing, and cleaning the windows. Active security means the protection against theft or direct attacks.