ASHRAE Discusses Reductions to Window-to-Wall Ratio

June 5th, 2013 by Editor

What if newly constructed buildings had 25 percent less glass than their older-model counterparts? The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) currently is circulating an addendum to one of its standards that would do just that.

The standard in debate is ASHRAE 189.1, Standard for the Design of High-Performance, Green Buildings. An addendum introduced to the green standard would reduce the glazing area allowed in the prescriptive path from 40 percent wall-to-window ratio (WWR) to 30 percent WWR for buildings less than 25,000 square feet, an effective reduction in the amount of allowable glazing by 25 percent.

The ASHRAE 189.1 proposal is open for public comments through June 17, at which point the 189.1 committee will hold discussions on the responses during the summer. If appeals from the window film and glass industries are not successful, the addendum will have a final presentation and a vote for publication late this fall.

To comment on the proposal, visit before June 17.

Click here to view a summary of the addendum.

What are your thoughts on ASHRAE 189.1? How would the implementation of this proposal impact your window film business? Email the editor at or comment below to share your views.

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