collated screws 25mm

[Rookery]

Sounds like he's planning to tile over 12mm ply or even thinner.

 

[Peter]

6-9 with 25mm screws by the sounds of things.

 

[Sean Kelly]

I don't know what collated screws are, but I use these for screwing through 6mm hardiebacker onto 18mm ply.
Toolstation > Screws & Fixings > Reisser Screws > Reisser Cutter Screw


They are 4mmx25mm 200 screws for £3.22 from Toolstation.

 

[widler]

Drywall screws are fine for screwing ply down, but id screw some hardy on top as well, with drywall screws, great things are dry wall screws