Plasterboarding ceiling

[ECP90]

Hello, 

 

I've pulled down my old ceiling, due to 100 years of cracking and fixing (it was old horse hair stuff). 

 

I'm looking to board my living room ceiling with my bedroom above it with 12.5mm plasterboard and to insulate it using rockwool for the soundproof mostly. 

 

Will 40mm screws be alright or should I use 50mm to take the extra weight of the insulation. 

 

Thanks in advance. 

[MikeSharp01]

Insulation weights very little and anyway the holding capacity of plasterboard screws is limited by the plasterboard not the screws because the screws just pull through it. 40mm will be fine just make sure you have plenty of screws. 

[torre]

3 hours ago, MikeSharp01 said:

holding capacity of plasterboard screws is limited by the plasterboard not the screws because the screws just pull through it

If you think you'll be heavy handed with the screwdriver, you can get special bits cheaply that stop you driving the screw through

[nod]

35s are fine