Hi John, without knowing how your sliding doors are made and how big the track is it is difficult to say , assuming you have bought them from wickes and doing them yourself i would allow another 50mm at the top and 50mm at the bottom for a frame to fix your track to. So you should allow 2460mm. You should measure different points along the lenght as the ceiling may undulate or change height especially if its an older building.
A.L. DECORATING SERVICES.
Your doors will need some sort of runners on the floor or on a baton on the floor and also down from the ceiling.
Check with the supplier of the sliding door system what their requirements are for the specific ones you have selected.
Normally allow room for a scribing panel above the top runners as ceilings are rarely level or perfectly parallel with the floor.
I would agree that the absolute minimum is 2400,it does depend on the system your using but if they are standard "Stanley" type steel frames from one of the DIY sheds this should be ok!But do check how level your floor is and the cieling because even though the measurements may be the same from one end to the other the room may not be level !I would strongly recomend that you pack out or build a level bttom sub frame for the track otherwise the doors may "wander on the track" once fitted,and this could reduce the overall hight you have to fit in !Hope it goes well!Cheers Pete
To fit standard door tracks to these doors you will need a minimum floor to ceiling height of 2400mm. If you have a greater height than 2400mm you can pack the tracks with spacer blocks or a height reducer. Failing this, you will need to look at made to measure doors.
This all depends on the construction method used. You will need to take into account the depth of the track and the batton you intend using to secure the track to both top & bottom.
You could screw a slimmer piece of timber directly to the ceiling joists and add a slim facing mould to the front and do the same at the base.
Hope this helps