Direct sun in the workplace is almost always a comfort problem. Uncomfortable occupants will be less productive, close their window coverings, bring in energy-using portable fans, and reduce thermostat setting if possible. Good shading means occupants will have minimal complaints. Shading reduces glare and can be accomplished by the use of:
Exterior Devices
Devices In the Window Pane
Interior Devices
Curvent International provides attractive exterior shading solutions that reroute punishing ultraviolet light away from your windows and help keep your interior temperatures at a more comfortable level. At the same time, they let in the natural sunlight that keeps your work crew alert and productive.
According to "Tips for Daylighting with Windows" there is a couple of key ideas when one decide to apply exterior shading:
Use exterior shading, either a device attached to the building skin or an extension of the skin itself, to keep out unwanted solar heat. Exterior systems are typically more effective than interior systems in blocking solar heat gain.
Design the building to shade itself. If shading attachments are not aesthetically acceptable, use the building form itself for exterior shading. Set the window back in a deeper wall section or extend elements of the skin to visually blend with envelope structural features.
Use a horizontal form for south windows. For example, awnings, overhangs, recessed windows. Also somewhat useful on the east and west. Serves no function on the north.
Use a vertical form on east and west windows. For example, vertical fins or recessed windows. Also useful on north to block early morning and late afternoon low sun.
Give west and south windows shading priority. Morning sun is usually not a serious heat gain problem. If your budget is tight, invest in west and south shading only.
Design shading for glare relief as well. Use exterior shading to reduce glare by partially blocking occupants’ view of the too-bright sky. Exterior surfaces also help smooth out interior daylight distribution.The shade’s color modifies light and heat. Exterior shading systems should be light colored if diffuse daylight transmittance is desired, and dark colored if maximum reduction in light and heat gain is desired.
Fixed versus movable shading. Use fixed devices if your budget is tight. Use movable devices for more efficient use of daylight and to allow occupant adjustment; first cost and maintenance costs are higher than with fixed devices. Use movable devices that are automatically controlled via a sun sensor for the best energy savings. Reliable systems have been in use around the world for years and have only recently become available as cost-effective options.
Source: https://windows.lbl.gov/pub/designguide/section5.pdf