Can drywall screws be used externally

[Neil]

Hi Folks,

Could you help clear up a debate please.

The question is, can/should drywall screws be used in an external situation? An example of the typical screw I'm referring to can be found at

item No. 12170, or generally any drywall screw.

Personally I wouldn't ever use them outside, but a friend tells me that they use them all the time in the building industry (southern England/ London area). I always understood that they were coated for protection against the plaster chemicals, not the weather elements.

I've googled for some authoritative advice on the subject but haven't come up with anything specific.

Many thanks,

Neil

[Franko]

I have used then outside on numerous occasions, always with the view to changing them for stainless screws if I could ever be bothered to get any - as of yet I haven't. Mainly they have been used for fixing fences and such like. I have used the silver anodised and the black coated ones and most, apart from a couple which were subjected to almost permanent moisture, have held up very well for a number of years. I would advise against it though if you are not as lazy as me (I have access to an infinite supply of drywall screws) as they can rust and discolour other items. The ones I used to fix hanging basket brackets have rusted and stained the wall, and the ones used to fix stainless lights to my decking have rusted through in a year. My advice - buy the proper article and you won't go far wrong. Franko.