Yes, you can install blinds outside of the window recess. It can be useful to do so if you have a recess that is too shallow to accommodate the blind. Or if there are obstructions within the recess (such as window handles or inward-opening window panes) that would prevent a blind from being installed. You may also just want to keep your window sill free. If you are intending to install your blinds outside of the recess, then you should submit the exact size of the blinds. As in, the finished width of the blind including any hardware and the finished drop of the blind including any hardware. We will manufacture the blinds to this exact size. The blind itself will need to be bigger than the recess size since when installed outside of the recess, we would usually recommend that a blind overlaps the recess edge by around 50mm on each side, top and bottom. You should consider that the blind will project outwards slightly from the face of the wall. You should also consider any obstructions around the recess itself.