Phosphor coated drywall screws - why?

[Adrian C]

Just doing some partition work with plasterboard. I've been supplied phosphor coated screws - what's the reason for the coating?

[David Lang]

Hi

Just guessing, to stop them rusting when wet plaster is put on top? Ordinary steel screws would rust mad that could bleed through?

Dave

[bigcat]

plain steel rusts, you get rust stains on the plaster, then the plaster pops off.

Probably more important with PB screws is the head shape. Ordinary woodscrews make a total dogs ear of PB.

I notice also PB screws are cheaper, and work fine in wood.

NT

[Rick Hughes]

It refers to phospate coating - anti-rust or you would have rust spots in finished wall.

Rick