# What Is the Groove Around The Window Frame For?



## Bird Doo Head (Dec 8, 2010)

Hi All!

While window shopping, I noticed that most of the brands of vinyl windows we viewed have a groove around the perimeter of the outside. It's on all four sides. I noticed that the one vinyl window in our house also has a groove on the inside. (Our other windows are wood and don't have the groove.)

Me being me, I forgot to ask what the purpose of the grooves is. Does it have to do with attaching vinyl siding or trim? I'm just curious...

A photo is attached. Two arrows in the photo point to the grooves.

Thanks Much for your advice!
Paul


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## XSleeper (Sep 23, 2007)

It is there for both strength (rigidity) and function. Most models of vinyl windows will have an accessory that can be snapped into the groove. Nailing fin on the outside if desired... an h-shaped jamb receptor on the inside.


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## Bird Doo Head (Dec 8, 2010)

Thanks for the information XSleeper. I appreciate the time you took to explain.
Enjoy Today!
Paul


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