TV Bracket On Plasterboard

[midas]

I'm trying to mount my 55" TV with a bracket over my fireplace.
The original brick chimney breast has been covered with plasterboard but there are no studs in the central section where the bracket
needs to be secured. The plasterboard is 30mm thick with a cavity behind and then brickwork. I was going to use Gripit fixings but they only
seem to go up to 25mm.
Can someone recommend the best way to get a secure fixing for the bracket please?


Thanks

 

[RandomGrinch]

Corefix Metal & Plastic 100 Heavy Duty TV Wall Fixing Kit 10 x 95mm 6 Pack

Order online at Screwfix.com. Corefix 100 heavy duty TV fixing kit for dot and dab walls (plasterboard over blockwork). Suitable for all brick and block types, including lightweight blockwork. Ideal for TV brackets with a maximum 10mm bracket/fixture thickness. Steel core bridges the gap behind...

www.screwfix.com

 

[foxhole]

Just standard plug and screws into the brickwork .