Will having the extra space between the outer frames and the walls of the boxes cause the bees to build burr comb there?
Sometimes the bees will build the end comb out and attach it to the wall of the box. You might have to run your hive tool back and forth at the wall to sever that comb. This is usually a small amount of comb and is not much of a problem. Just be careful not to tear open the cells in the frame.