Tips on glue for double layers of chipboard

[benke_berguv]

Hello.
I am thinking of adding another layer with chipboard in the cabin on top of the chipboards that are there today. The plan is to lay it perpendicular to the existing floor and not screw it but just glue it down (to avoid screw heads that may be visible in the wet room mat later).
What kind of glue should I use?
It's 30m2 that needs gluing, so a reasonably cheap option would be preferable.

//Henrik

 

[Helioz]

Common wood glue/winter glue, but you still need to screw them down for the glue to adhere properly. Once it is dry, remove the screws and fill the holes with spackling paste.

 

[benke_berguv]

Aha, of course, you have to get it tight against the other board..
Regarding the glue question, it's 30m so it would be quite tedious to go with small bottles. Are there larger packages available? Tried googling a bit but the only larger one I found (15 liters) was Gyproc g46 but that was probably for drywall

//Henrik

 

[Stefan N]

Available in any case in 5L.

 

[benke_berguv]

Oh, perfect!
Found at the local hardware store with: http://www.lakkapaa.com/lakka_se/showProduct.do?id=7311980111550&mode=search

Thanks for the replies!