U Factor of a Window
user-6226553
| Posted in Energy Efficiency and Durability on
Hello,
We have a contractor who claims that they installed the correct windows, but the suppliers had included the incorrect NRFC label. We would like to confirm the actual U Factor of the window, if possible.
We have a Window Profiler WP4500, which measures UV (in %), Visible (light in %), Infared (%) and SHGC. Does anyone know if its possible, with this tool or at all to confirm U Factor?
We have also reached out the manufacturer of the Window Profiler. This is for Climate Zone 2.
Thank you.
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Replies
Sarah, unfortunately all of those values are independent of U-factor, but there are a limited number of different assemblies available, so they should help you narrow down your options. You would need to know who manufactures the actual glazing, which is rarely the window manufacturer.
U factor takes into account all of the heat transfer from one side of the window to the other, through both the glazing and the frame. I don’t think there is any simple tool to make this measurement, you'd need a full laboratory setup to do it correctly.
I would look to see if the windows have a serial number on a tag somewhere. If they do, call up the manufacturer and ask the manufacture for the specs that particular serial number window was built to. This is the most reliable way to know exactly what you have.
Bill