PIR plasterboard fixings - plastic cover caps or tape over?

[SJRSJR]

Hello

I'm putting up 62.5mm PIR plasterboard via dot and dab and was going to use Timco metal PIR fixings as a secondary mechanical fixing. I planned to tape over the heads but I see they do plastic cover caps which says 'help' eliminate cold bridging. Are they a good idea or will taping over suffice? Thanks

 

[Wayners]

You using foam or powdered adhesive to fix PIR.
Get a good fixing you don't really need anything else but to answer, use the plastic.
Then tape over.
You using tapered edge PIR?

 

[SJRSJR]

Thanks. Will be using Knauf adhesive and tapered edge PIR.

I thought the mechanical fixing was advised e.g in case of fire - not as many fixings as you would if it was the primary fix?

 

[Wayners]

Like this

I prefer foam

 

[SJRSJR]

Yes, I’m following Charlie..

I’m thinking dot and dab will better on a full wall where I need to level it up, and maybe foam on the reveals.

Why do you prefer foam, and which brand?

 

[Wayners]

Foam is not effected by any damp.
It's not brittle.
Easier to use.
Less mess.
Just not much grab with it so I use a bit of polymer grab with the foam.

Low expansion foam for board. Any