Bay windows can appear a little tricky to measure, please find below a helpful guide which we think might help you.  Remember, this is only a guide so please feel free to deduct more if you think this is appropriate.

Firstly, you have to remember that the tracks cannot go right into the corners, they have to be placed so that when your roman blinds are up they do not clash with the blind next to them.  The measurements below are the recommended minimum adjustments.  If you are having extra long blinds or having interlining which can make the blinds thicker, you may want to deduct a little more at the angles as the folds in the blinds may protrude more.

Please note the depth of the tracks:
Manual tracks = 3cms
Sidewinder tracks = 4cms

Note: The guide below is based on manual tracks (if using sidewinder tracks please adjust accordingly).

Right Angled Bay Window A = width minus 8cms B = width minus 5cms C = width minus 5cms

Three Sided Bay Window   A = width minus 6cms B = width minus 4cms C = width minus 4cms

Five Sided Bay Window A = width minus 6cms B = width minus 6cms C = width minus 6cms D = width minus 4cms E = width minus 4cms