On 20 Nov, 18:49, stuart noble wrote:

They do 8x2 flooring chip (if you can get it through the hatch)

I'd always use OSB rather than small-chip chipboard. Less sag over
time, less prone to moisture-related sag and a bit lighter all round.
If you can't buy it as 8x2, then the seller will rip it down for you.
Probably makes transport easier too.