Consideration of the width of the apron is perhaps not taking all factors into consideration - I think that the size of under apron pleat - and perhaps the reverse pleat as well - the two together make an inverted box pleat at the edge of the apron and under apron, is significant in how freely the aprons drop when sitting.

With a narrow apron, the under apron should really be extended rather than reduced, possibly with a reverse taper, so that even if the apron lifts or flips modesty is preserved. Otherwise, a zip, line of poppers, Velcro, buttons, lacing - something to make a mechanical join between the two aprons should be considered, or perhaps a detatchable third layer, or a kilt liner improvised.

Another thing to consider is the sewing down - or not, of the edges of the apron. I leave them entirely free, so the under apron pleats can fall open easily and that seems to be advisable for any kilt where there is climbing over styles, stepping over obstacles, vaulting gates and the like, as it means that when the knee is raised the apron drops.

It seems that no matter how much fabric there is in the pleats, they will always tend to fall backwards on the outside of the thigh, and - from experience - a good deep under apron pleat - with a reverse pleat if appropriate, is the requirement for a vertical apron under almost all circumstances.

Anne the Pleater :ootd: