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How to repair a wooden window frame

Getting someone else to do a job for you can be costly. But with the right approach you can do a lot by yourself. You’ll save time and money by using the handy step-by-step instructions that you’ll find on the SKIL website. These step-by-step instructions are divided into categories relating to the different kinds of jobs in and around the home, and give you clear, A to Z explanations.

Just click on one of our step-by-step instructions and you’ll be able to get started right away!

  1. Remove all the rot

    First check carefully that there’s no danger from breaking glass while you’re working. Then use a hammer and chisel to remove all the rotten wood.

  2. Clean well

    Make sure you completely remove any remaining smaller rotten areas in the window frame. Clear out the debris and clean the working area thoroughly.

  3. Treating with wood filler

    When everything is clean, treat the affected area with wood filler. This acts as both an adhesive and a filler. Sand the area after drying, then apply a finishing layer of filler, allow to dry and sand smooth. After that you can paint the window frame.

  4. Replacing larger sections

    If the wood rot has affected a larger area, it’s best to replace a complete section of the window frame. It’s better to remove a bit too much sound wood than to leave some of the rotten wood untreated. Try to make the edges of the opening as straight and square as possible, and then clean the working area thoroughly with a vacuum cleaner or brush.

  5. Make a replacement section

    Make a new section in the same shape and out of the same kind of wood to replace the piece you have removed, so that it fits exactly into the opening.

  6. Fit the replacement section with epoxy resin

    Coat both parts with undiluted epoxy resin. Let the resin set briefly, and then fit the new section into the opening. Epoxy resin also acts as a filler, so you can use it to fill any gaps between the new section and the window frame.

  7. Sand and paint

    When you’ve completed the repair, all that’s left is to sand the working area so that it’s flat and smooth, and then finish the job by painting.


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