Information · LEED

LEED

Information
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What is LEED?

LEED (Leadership in Energy and Environmental Design) is the green-building rating system of the U.S. Green Building Council (USGBC). It is voluntary, though some owners, institutions and cities require it. Projects earn points across energy, water, materials, indoor environment and site categories and are certified at four levels:

LevelPoints
Certified40–49
Silver50–59
Gold60–79
Platinum80 and above

LEED v4 and v4.1 are still widely used. LEED v5, released in 2025, reorganizes every credit around three goals: decarbonization, quality of life, and ecological conservation and restoration. It puts more weight on electrified, high-performance buildings, operational and embodied carbon, resilience and occupant experience. Older programs, such as the Core Performance prescriptive path used under LEED 2.2 and 2009, are no longer part of LEED.

How windows contribute to LEED

Windows do not earn LEED points on their own; the building does. But they affect several of the largest credits:

  • Energy performance. The biggest block of points rewards energy savings shown by whole-building energy modeling against ASHRAE 90.1. Low U-factors, tuned SHGC and airtight frames cut heating and cooling loads, and very good windows let designers downsize or electrify mechanical systems.
  • Daylight and quality views. LEED v4.1 has separate Daylight and Quality Views credits; LEED v5 folds daylight simulation, views, thermal comfort and visual comfort into a single Occupant Experience credit. High visible transmittance and large, comfortable glass areas help.
  • Thermal comfort. Warm interior glass surfaces reduce radiant chill and drafts near windows, so perimeter spaces can be used year-round.
  • Acoustics. Laminated and vacuum glass reduce outdoor noise, which supports acoustic comfort criteria.
  • Enclosure commissioning. LEED v5 brings building enclosure commissioning, including fenestration and air-barrier verification, into the fundamental commissioning prerequisite.
  • Materials and embodied carbon. LEED v5 requires projects to assess and quantify embodied carbon, and rewards reductions and product disclosure. Durable products with long service lives help, because they are not replaced.

What we provide for LEED projects

For energy models we provide whole-window U-factors and SHGC, THERM files for frame sections, and the Passive House Institute’s certified frame and installation values. For comfort and daylight analysis we provide center-of-glass values, surface temperature factors and glass package data for each ZERO package. Ask us for the data package for your project.

LEED credit names and structure summarized from USGBC’s LEED v4.1 and LEED v5 rating systems. Confirm credit requirements with the current USGBC reference guide for your project type.