Sorting varchar w/single digits

I have varchar column with both numbers and letters, like 1 thru 10 and
5A thru 5G, they are unit numbers for apartments. If I have 1 thru 100,
since it is a varchar field, it sorts like 1,10,11... instead of
1,2,3...

Is there any way to handle this without having to make a sort order
column?

--
Robert