Energy

• It is important to choose windows that are energy efficient, as this saves energy as well as costs to the school. Factors that should be considered include the insulation value, visible transmittance, solar heat gain coefficient and air leakage.
  
  

Learning

• Making an informed window choice can positively affect the learning environment. For example, natural light, pleasing views and fresh air keep young minds alert and focused. Skylights and other top lighting should be considered in additional to normal wall windows.
  
  

Seasons

• Consider how window importance varies by season. For the winter, performance factors include ability to control heat loss and ability to prevent discomfort resulting from cold window surfaces. Summer performance varies mainly according to the orientation of the windows with respect to the Sun.