Go for it! Our latest renos saw us try different treatments, small through to bigger compound moulding, built up with smaller pieces.
Take your time! Prime and paint before putting up, DAP is your friend!
And if you haven't already, learn how to use that coping saw!
This was the most challenging: I've always loved coffered ceilings, so we went with a simple faux coffered that isn't too heavy for our small dining room. We did try painting the blue between the crown and the smaller trim, but it was too much.
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