Barre chords are transpositions of open chords; the root note stays on the same string:
- An open E chord has the root on the 6th string, and so does any E-shape barre chord.
- An open A chord has the root on the 5th string, and so does any A-shape barre chord.
- An open D chord has the root on the 4th string, and so does any D-shape barre chord.
Any open chord that you can transpose as a barre chord will follow the same rule, e.g. a C chord has the root note on the 5th string (third fret), so a C-shape barre chord also has the root on the 5th string (third fret above the barre).