glass area of replacement windows

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glass area of replacement windows

#1 Post by riversilk » Mon Jun 15, 2020 1:58 pm

Been looking for replacement windows. Several of the brands I checked out like Stanek, Pella seem to lose an additional inch of glass except for the Marvin Infinity. Wondering how other windows fare like Okna or Andersen?


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Windows on Washington
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Re: glass area of replacement windows

#2 Post by Windows on Washington » Tue Jun 16, 2020 11:19 am

You can effectively compare glass loss if you compare the VT numbers (assuming similar Low-e coatings) between the windows.

A replacement style insert window will net a smaller glass opening vs. a full tear out, but the benefit is the lack of disturbance and installation costs.

The edge of frame to edge of glass measurement on the Infinity is pretty small at around 2 5/8". By contrast, and Okna 500 is about 2 3/4" so little to no difference.

Thermal performance and air infiltration are much better on the Okna so I would gladly trade that 1/8" of glass per side for a window that will perform much better.

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