Grippit fixing into shower backing board?

[datadiyer]

Hi all,
I have a new stud wall loft conversion where I'm fitting the shower. I've put 9mm ply over the shower walls to make it more rigid. I'm now fitting shower backing boards from NandC tiles, but on one of the sides of fixing the backer board, I've messed up and have no stud or noggins behind it, just the 9mm ply.
Can I use a Grippit fixing to remedy this and smother it with silicone afterwards? It's going to be tanked also.
Thanks in advance.

 

[sircerebus666]

Why have you messed up? Just screw it to the 9mm ply

 

[datadiyer]

Why have you messed up? Just screw it to the 9mm ply

Will it hold tight enough tho do you reckon? It's a 10mm backer board over 9mm ply. Should I use some kind of plasterboard fixing to pull them tight together or will just a screw do.
Many thanks in advance

 

[denso13]

or will just a screw do

Screws will be fine, you'll get a good fixing in to 9mm ply.

 

[Madrab]

The only question I would ask is, if there are no studs/noggins, what's holding the original shower wall up?

 

[datadiyer]

The only question I would ask is, if there are no studs/noggins, what's holding the original shower wall up?

There are studs and noggins, it's just that the edge of the backer board hasn't landed on any of them. I've put silicone around the other edges also so it would be a right pain in the **** to take out.

 

[dilalio]

It'll be fine. If the tilings done proper, it'll all hold up together.

 

[Madrab]

Ah right, no bother there then as long as the ply is screwed on properly then crack on.