Suspended floor insulation - need for a membrane?

[RichD1]

I’ve read all the previous threads about this topic but it doesn’t resolve my query.

I am going to use 100mm fibre insulation between the joists supported by mesh/netting underneath but do I need a vapour proof membrane over the top before relaying the floorboards?

The floor is well vented underneath and the insulation will be well clear of the air vents.

Richard