See the benefits of Pella’s interior pocket replacement installation method.

Why is proper installation so important?

See the video below to learn more about Pella’s unique methods to ensure exceptional energy performance and smooth operation.

How it works:

Only the sash of the old window (the part that holds the glass) is removed. The new window slides neatly into the existing frame.


  • Less installation time and labor—installation can typically be completed in about an hour per window
  • Installation uses Pella’s exclusive SmartFlash® installation tape and Great StuffTM 1 Pro Window and Door Insulating Foam Sealant
  • Includes a full perimeter sealant, such as OSI® QUAD®, to help keep out air and water


  • Less glass area
  • Uses the existing window frame