PQ-Enter blank row after group of cells or empty cell is detected

how can I get the data on the left to now have an empty row in between each room number?

Original			Result
Room #	Room		Room #	Room
a1	kitchen		a1	kitchen
a2	bedroom
a3	living room		a2	bedroom
	dining room
a4	stairs		a3	living room
a5	restroom			dining room
	powder
a6	lobby		a4	stairs
			a5	restroom
				powder
			a6	lobby

Code:

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// Table1
let
    Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
    FD = Table.FillDown(Table.DuplicateColumn(Source, "Room #", "Room # - Copy"),{"Room # - Copy"}),
    Grp = Table.Group(FD, {"Room # - Copy"}, {{"All", each Table.InsertRows(_, Table.RowCount(_), {[#"Room #"=null, Room=null, #"Room # - Copy"=null]})}}),
    RC = Table.RemoveColumns(Table.ExpandTableColumn(Grp, "All", {"Room #", "Room"}, {"Room #", "Room"}),{"Room # - Copy"})
in
    RC

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