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Recycled replacement windows: how do I finish exterior?

mikeysp | Posted in General Questions on

Hi. I am in zone 4a.

I have a bunch of replacement windows that were removed from a house during a remodel and I plan to use many of them on my shop/in-law suite. (pics below).

I am uncertain how I will trim the exterior side of a replacement window while ensuring a watertight seal.

In the past when I have used vinyl windows; but, they had J-channel and a nail flange. These replacement windows obviously lack the J channel and a flange. 

Does anyone have any ideas on how I might solve this dilemma?

Thank you for your advice. 


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  1. walta100 | | #1

    Without the original window frames I do not see how you can make them waterproof without recreating the frames.

    Seems to me like you would be better off with new windows from the home depot.


    1. mikeysp | | #2

      They were $5 each, so I hoped I could fabricate something.

  2. Expert Member
    Akos | | #3

    Can you take a picture of the outside? Most have grooves for metal trim.

    1. mikeysp | | #4

      Akos, here are pics:

  3. jonny_h | | #5

    Can you treat them like a flangeless (European style) window install? Flash the rough opening -- sloped sill pan with a back dam (either bent metal, or built up with wood and then covered with a membrane or fluid-applied flashing product), tape the face of the window to the WRB, and then cover the tape with window trim. Someone in a similar position here:

  4. Expert Member
    Akos | | #6

    Looks like the windows still have a bit of a flange on the outside. I would treat this similar to a flanged window, connect your WRB to this flange, install head and pan flashing and trim as per the link bellow. This way if the windows every need to be replaced, you can simply install standard flanged windows.

    Notice that the sill exits bellow the bottom trim and the head flashing is above the top trim.

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