All window shades have a rating called a shading coefficient which is the ability of the window covering to transmit or block solar heat. The shading coefficient is expressed as a number between 0 and 1. The lower the shading coefficient of window shade, the less solar heat it transmits and the greater shading ability it has. A window covering that reduces heat by 75% has a shading coefficient of 0.25.

Honeycomb Cellular Shades

Honeycomb shades offer the highest shading coefficient among window coverings and are the best energy efficient blinds. Cellular shades are great for blocking hear. Typical shading coefficient for cellular shades are between 0.25 and 0.45. The shading coefficient will vary by product. Cellular shades vary by pleat size, number of cells, as well as light filtration. Each of these factors control the shading coefficient of the cell shades.

Solar Screen Shades

Solar screen shades have a shading coefficient between 0.3 and 0.6. Their amount of solar heat they block depends on the tightness of the screen. Solar screen shades allow light to enter the room but block a large portion of uv rays. They are not privacy window shades but work well in rooms where you don't want to block the view.

Roman Shades

Roman shades have an approximate shading coefficient of 0.3. Roman shades are another great way to insulate your window, block solar uv rays and save energy.

Soft Sheer Shades

Another good shade to block the sun is soft sheer shades. They have a typical shading coefficient of 0.35. Soft sheer shades are unique because the vanes can be raised or tilted like horizontal blinds. When the vanes are tilted there is still sheer material filtering the light and blocking the sun.

Each window shade will provide some sort of shading from uv rays. Research each window blind or shade for their exact shading coefficient so you will know which are the best energy efficient shades.


Blinds Chalet has more than 25 years of experience selling and installing window shades. Attractive, high quality window blinds that fit any energy saving plan, decorating style, and budget. For information on what types of window blinds, blind accessories, and any other window covering needs, visit
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