victorian house - suspended floor insulation

[finallynearlyhomerenovating]

Hello,
After one year, we are finally on track to start our home renovation works in May, to renovate ground floor and replace kitchen.
We have 2 reception rooms (classic victorian semi with 2 reception room + galley kitchen) and before the winter we moved our main living area to the reception room adjacent to the kitchen ( which we are going to turn into a kitchen diner). I like to have the living area in an inside room as it much quieter but I have realized during the winter the room is very cold, something that never really seems too much of an issue when we were using the reception room facing the road.
This internal room is a walk-through with staircase to first floor. The floor is old suspended solid wood with no sign of insulation underneath which we were planning to sand and reseal, but now I am wondering if it would be better to lay a good laminate flooring on top as it would allow us to add an insulating underlay.

Has anyone faced a similar issue? I don't think I will be able to afford to lift existing floor to insulate underneath as it will likely require to replace most of the planks (they are glued) though I haven't discuss this amendment with the builder yet. Another thing I am wondering is whether I should enclose the staircase to retain more heat in the room, although I quite like the look of the open staircase!
Thanks in advance for your suggestions.

Are the boards nailed to the joists below? Where is the glue? If you want the look of the sanded/varnished boards then try to get them lifted and insulate underneath. Or, you can buy a sort of flexible tubing that you squash into the gaps between the boards that would help with insulation and wouldn't require lifting any boards.

Careful about open staircase + open plan kitchen/diner with building regs.

We insulated underneath our floorboards and sanded/varnished - love the look and it's much warmer now, but they're not as practical to keep clean etc so will be laying engineered wood on top (sadly - I love the look of them!). Something to consider!

@bravotango thanks for the suggestions. And you are making a very good point on how difficult is to keep wood floor looking nice, mine is full of dent/scratches though I love the look. Reception room and kitchen/diner are going to be separate rooms, the only reason I mentioned is because I feel the fact the staircase is not enclosed does contribute to the heat loss

Ah right ok. Well insulating underneath the boards made an instant difference to us, in quite a large and draughty open plan room, so I would imagine it would make a good difference for you! Are you going to DIY sand? See if you can do the mixing the sawdust with PVA and filling the gaps thing - we didn't and that meant we really did have to insulate underneath!

If you are going to the trouble of renovating then personally I would lift the floor completely.
I know it's extra faff and cost but at least you get to inspect for any rot on the joists and clear any air vents while you do it, plus once back down and sanded it will look stunning.
Be wary of too much insulation cutting off the air circulation under the floor. If you do that the floor will rot as moisture levels will rise.