Sunlight

• Both sheer curtains and semi-sheer curtains allow sunlight to pass through the fabric. Since sheer curtains are designed thinner, they are also more transparent. This lets nearly all the light pass through, so that having a sheer curtain is almost like not having a curtain over the window at all. Semi-sheer curtains, which are slightly thicker, block some of the light, so that the light coming in is filtered more.
  
  

Privacy

• If you want your curtains to provide some level of privacy from neighbors, semi-sheer curtains are more effective than sheer curtains. Since sheer curtains are transparent, they provide almost zero privacy. Semi-sheer, on the other hand, provide some privacy. Neither sheer nor semi-sheer curtains provide the privacy of standard curtains, however. If it's dark out and the lights are on in a room with sheer curtains, passersby will likely be able to see in from outside.
  
  

Coloring

• Like standard curtains, sheer and semi-sheer curtains come in a variety of colors and designs, which allows you to incorporate them into nearly any window treatment. Since coloring blocks light from outside, the darker a sheer curtain, the more likely it is to appear semi-sheer. The sheer curtains that allow the most light to pass through are white or cream.
  
  

Hanging the Curtains

• Hang sheer and semi-sheer curtains on curtain rods like any standard curtain. If you want light from outside and don't mind the lack of privacy, you can hang sheer and semi-sheer curtains alone over the window. If you would like to block light and prefer privacy in a room, layer sheer curtains with solid curtains to create a distinct look.