multi purpose screws or drywall screws???

[Eddman]

I have underdrawn my sloping roof rafters with 50mm insulation, i'm fixing 9.5mm plasterboard through the insulation to rafters - i have purchased a tub of 5x75 multi-purpose single thread screws from B&Q - will these be ok to use or shall i go to screwfix and get some 75mm drywall screws?

What are the pitfalls of using the multi purpose ones - if any???

thanks
Eddy

 

[joe-90]

There's no real difference for that. The pb screws have a flatter head, not so conical so hold the board a bit better, but the others will do.

 

[Eddman]

thanks Joe

 

[geraldthehamster]

Plasterboard screws will drill into the wood better, and the heads are designed to hold the board without breaking the paper. See how you go.

Cheers
Richard