I’ve had more people asking about J-channeling around windows lately. I found this video from a warmer time where I was showing one way to do it. This is one of the many methods to J-channel. I prefer a different way which I’ve also shown before. Some siding manuals show J-channel cuts with no mitre, some installers choose to make the mitres to a point (I don’t so it doesn’t snag or scratch anyone and also to allow for expansion and contraction). At the end of the day, whatever style you choose,

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