Replacing chipboard flooring.

[rekha66]

Hi
I have a bit of a problem with the chipboard flooring, as they are damaged and creaking really badly, I have decided to replace them.
The chipboard is varying lengths and 2 feet wide and there are 6 rows of it and only the middle ones are not affected.
My concerns are that the old chipboards are 25mm and this is hard to get hold off, can I use 18mm and will this be strong enough?
And should I get some lamminated flooring to go on top to bring it up to the same height as the old chipboard or do I need to do the whole lot.
The room is upstairs and the chipboards are nailed to the jousts.

Any help will be gratly appreciated.

[seneca-boy]

if it was me i would rip up all 25 mm flooring replace with 18 mm chipboard flooring and remember to glue all round joints as you lay it , then lay 6mm ply at right angles to that to make up the shortfall