My neighbor's side porch is built up to the property line (i.e. there is zero setback). There is about 10 feet between that porch and our house - it's just entirely our 10 feet. Our neighbors mentioned they "have an easement" that says their porch is okay but no such easement is recorded on our property (according to our title insurance). Are they in violation of the zoning code (no setback) or could they somehow argue they have a prescriptive easement? Or is there any adverse possesion of setback space or something?