Head height needed over top bunk?

[JugglingChaotically]

Can anyone tell me how much head height you need over a mezzanine bed or top bunk. The distance from base of mattress to ceiling is 1400cm. Is that enough? It's in a sloping room so much less at the foot of bed.
Can't visualise at all so would really appreciate anyone's experience on this. Thanks

Only enough so they can climb in. Is the ladder at the top of the bed or in the middle?

I think that sounds plenty. Enough for a child to stand on the top of the ladder and climb in.

As long as the ladder is at the middle/top of the bed and not the end where the ceiling slopes down.

Thanks. Ladder will be at high end.
Planning for the longer term, would it fit a teen also? Thinking of loft style with desk under.

IKEA recommend a minimum of 95cm for their loft beds.

Enough that they can sit up in bed, even when grown.

Pre-nuclear submarines had bunks where you had to slide in on your back. If you wanted to turn over, you had to get out and slide in on your front. Vile.

Sitting-up room, essential. Kneeling room, luxury.

Ok. Just measured 6'2" husband sitting its 90cm. Kneeling up is too high but sitting up back on heels (if goth know what I mean) still gives clearance.
Thanks all.
Was worried that I was doing something in doable!