Russell Tauscher is the President of the Expanded Metal Manufacturers Association (EMMA). The EMMA division has completed tests showing the effectiveness of expanded metal used as a screen for openings. For details of the three tests, see the links below. The range of values for SHGC (Solar Heat Gain Coefficient) is from 0 to 1. A window with no shield for solar gain has a higher rating approaching 1.
When a screen is added the value is reduced to less than one. The EMMA solar heat gain test shows that the value for all three tests ranges between 0.1 and 0.5, meaning the heat gain reduction to one tenth to one half depending on the angle of the sun.
The Expanded Metal Manufacturers Association (EMMA) is comprised of North American Manufacturers of expanded metal materials. It is a trade association whose main mission and objective is to promote the increased use of expanded metal manufactured in North America through education, marketing, and standards development. The Association develops and supports programs and activities to advance these objectives.
EMMA member companies conduct studies and technical research on product applications, promote activities designed to broaden the markets for expanded metal, and create wider use of its products and services. It also prepares and updates useful industry standards and tolerances to assure member companies provide a consistent and superior level of quality.