OSB3 vs Ply vs floor boards - Please help!!!

[Hl.house]

If you glue then screw the top sheet down it would help, I would have thought 18mm ply would have been fine for a floor as long as you noggin each joint...

Thank you tomfe. I can spend the holidays without worrying. You have just bough a sigh of relief for me.

My room is only 2.6m wide so a single 2.4m sheet covers most of the width. I have no joints in between joists. Only one joint per sheet on the last joist. Sheets are fitted in staggered pattern. Where exactly should i add noggins?
Forgot to add, space between joists is approx 32cm.

 

[Ian H]

I'd add noggins at the board ends between the joists.

 

[Hl.house]

I'd add noggins at the board ends between the joists.

Thank you 1990.
Both ends of the long board(approx 220cm long) long are on joists. Both ends of the short board(approx 40cm long) are also on joists. Two boards are closely fitted next to each other. So, there are no board ends between joists. So I need to add trimmer joists where the boards end?
I am missing something?
Have a very happy x'mas.