Home Improvement Questions? Ask a Handyman for Answers
Welcome to Just Answer, my name is ***** ***** I will do my best to help you with your issue. If my initial response doesn’t answer your question then let me know and we can continue our conversation.
1) There really isn't anything you can do to make that height difference disappear unless you're real good at working with Bondo and if the window and the stool cap (sill) are the same material. If you're not an auto body mechanic or a highly skilled amateur I'd leave it alone.2) From what I can see in the picture it's not the bet result. It's more a poor choice than poor workmanship. There are basically 2 option when dealing with this situation. You either get both the window and the stool at exactly the same height but this may not always be practical given the potential for slight variations in the 2 surfaces. The other option is to not try and hide it. To leave a reveal (usually ~1/4") like you have where the casing meets the window. The latter is the more common method.
That said if you're not happy with the options I mentioned then I'd go back to the installer and express your dissatisfaction
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