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Leaking Replacement Window

Ryan_SLC | Posted in General Questions on

Window leak with aluminum siding and replacement window

Hey all,

While working on the addition to perfection…my wife protectively and successfully let me know a window on the second floor we had replace a year or two ago is leaking so bad that the inside corner drywall is bubbling.

Exterior is aluminum siding with no type of trimming around it that I can see. Window has a built in trim.

Without building perfection with tear out and new siding and flashing and all that…can I just go gun happy with silicon behind the trim?

The wife said she would totally get someone to take care of it. But if it’s just a person that is going to silicon caulk…I can do that.

Thank you all

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  1. Expert Member


    You can try that, but without knowing what caused it to leak, it may or may not work. The problem with that approach is you are gauging success by what appears on the interior - which means there may be extensive ongoing damage to the sheathing and framing, that as long as it doesn't make its way to the drywall, you won't know about.

  2. walta100 | | #2

    Most replacement windows only replace the sashes and balances. The original frame, sill and flashing remain in place and hopefully are still up to the job of keeping the water outdoor. Generally caulking is the only thing that keep water from getting in between the new window and the old frame.

    The same is true when new siding gets installed generally right over the old siding with the hope that the original siding and flashing will keep the water outdoors.

    The worst case is the new siding and windows have trapped water and it has allowed the original stuff to rot away. Unless some one is willing to open the can of worms and fix it correctly then it is all caulking and Band-Aids.


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