Shading the window (especially West and South facing windows) in summer afternoon keeps your home cool and saves electricity, puts less load on the AC, and makes the space comfortable. Shading windows effectively is also a passive cooling strategy, that can be accomplished by blinds, roller shades and curtains. The following should be considered when choosing the shades for your windows:
Room type: The choice of the type of windows shades should be driven by the room in the house and its usage:
1) Bedroom: The bedroom should be shaded by fabric shades such as curtains or roller shades that can block the light completely, to allow for a peaceful sleep. Look for 0 visual transmittance shades. Sheer fabrics can be matched with the curtains to let in diffused light when needed.
2) Bathroom: Plastic blinds are ideal for bathrooms. Some sunlight filtering through the room (assuming translucent windows), is also healthy and ensures minimal molds in bathrooms. Metal/aluminum or wooden blinds should be avoided because of the water/humidity in the bathrooms.
Choice of the type of windows shades should be driven by the room in the house and its usage
3) Kitchen: Plastic or Aluminum blinds work the best in kitchen, as they can easily be cleaned, as compared to curtains or fabric roller shades.
4) Living Room: Fabric curtains/drapes work well in the living room and can be matched with the overall decor and style of the space(including matching with the sofa upholstery and wall colors and accents). Sheer fabrics can be matched with the curtains to let in diffused light when needed.
Window Orientation & Size
Windows facing the West and the South-West side should be shaded well to prevent solar gain during hot summer afternoon. Also, ensure that large windows are shaded on the South and East side.
Smart Window Shades: Automatic Shading
There are smart motorized automated shades available that can be operated automatically based on a per-determined schedule, to shade the interiors and minimize AC loads in summers. This strategy can cut down the electricity bills significantly, especially in a house with large expansive windows for days when there may not be anyone in the home to turn on the shades, or if you are on a vacation.