menu pointer
Title 24, Part 6 Energy Code Compliance Forms
Residential
2022 Forms
2019 Forms
2016 Forms
Nonresidential & High-rise Multifamily
2022 Forms
2019 Forms
2016 Forms
Low-rise Multifamily
2022 Forms
Forms Ace
Virtual Compliance Assistant
Live
Online Self-Study
Recorded
Annotated Forms
Fact Sheets
menu pointer
Title 24, Part 6 Energy Code
Forms Ace
Image Ace
Navigator Ace
Nonresidential Lighting Wheel
Product Finder
Q&Ace
Reference Ace
Timeline Ace
Virtual Compliance Assistant
Live
Online Self-Study
Recorded
Application Guides
Checklists
Details
Fact Sheets
Noteblocks
Outreach Materials
Trigger Sheets
Useful Links
Submit a Question
menu pointer
Title 20 Appliance Efficiency Regulations
Q&Ace
Reference Ace
Timeline Ace
Live
Online Self-Study
Recorded
Fact Sheets
Outreach Materials
Submit a Question
Useful Links
menu pointer
My Profile
My Projects
My Collections
My Messages
Submit a Question
Sign Out
Sign in to access your messages, projects and collections!
NA6.4 Default Visible Transmittance, VT
Equation NA6-3 - VT of Center of Glass (COG) calculation

VTT = VTF x VTC

Where:

VTT = Is the Total Performance of the fenestration including glass and frame

VTF = 0.53 for projecting windows, such as casement and awning windows

VTF = 0.67 for operable or sliding windows

VTF = 0.77 for fixed or non-operable windows

VTF= 0.88 for curtain wall/storefront, Site-built and manufactured non-curb mounted skylights

VTF = 1.0 for Curb Mounted manufactured Skylights

VTC = Center of glass VT is calculated in accordance with NFRC 200 Section 4.5.1.1 or NFRC 202 for Translucent Products or NFRC 203 for Tubular Daylighting Devices and Hybrid Tubular Daylighting Devices or ASTM E972 (http://www.nfrc.org/software.aspx)

This panel displays referenced content when certain links are clicked.

Terms of Use About this Site Contact Us
Energy Code Ace Privacy Policy PG&E Privacy Policy Social Media Policy
This program is funded by California utility customers and administered by Pacific Gas and Electric Company (PG&E), San Diego Gas & Electric Company (SDG&E®), and Southern California Edison Company (SCE) under the auspices of the California Public Utilities Commission.

© 2024 PG&E, SDG&E and SCE. All rights reserved, except that this content may be used, copied, and distributed without modification. Neither PG&E, SDG&E, nor SCE — nor any of their employees makes any warranty, express of implied; or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any data, information, method, product, policy or process disclosed in this document; or represents that its use will not infringe any privately-owned rights including, but not limited to patents, trademarks or copyrights.