French & bi-fold doors may appear similar and in some respect they are- because you can get bi-fold French door frame, but there are some differences. French door frames are effectively two doors that open outwards or inwards, whereas bi-fold may include a few panels or glass paneled doors that can fold back, almost as a modern replacement to the sliding patio door.
Bi-fold doors are incredibly effective at giving your home a fresh and airy feel. You can literally feel like you’re in the great outdoors while still being in the comfort of your own home. Like French doors, these can be opened on warm sunny days but are also extremely efficient at keeping heat in.