What is the difference between coarse thread and fine thread plasterboard screws?
It comes down to what you are screwing into. Coarse thread screws have a wide, deep thread that grips timber. Fine thread screws have a tighter thread cut to bite light gauge metal. These are coarse thread, so they are for timber stud work. Use a fine thread screw on a metal stud instead.
Can I use these on a metal stud wall?
No, keep these for timber. A coarse thread does not hold reliably in metal and can strip. For metal studwork you want a fine thread plasterboard screw, which we also stock.
What is the black finish on these screws?
It is a dark grey phosphate coating. It reads as black, which is why they are sold as black plasterboard screws. The phosphate cuts friction so the screw drives in more smoothly, and it suits dry interior work. It is not a weatherproof coating, so these are Corrosion Rating 1 for inside use only.
Are these fully threaded?
Yes. The thread runs the full length of the shank. That gives you consistent grip through the board and into the timber the whole way down.
What length do I need?
A common rule is to pick a screw that goes at least 20mm to 25mm into the timber past the board. For a single 12.5mm board a 32mm or 38mm screw is a typical choice. For thicker or doubled boards, step up the length. These start at 25mm and run up from there, so match the length to your board build up.
Do they meet the plasterboard fixing standard?
Yes. They are made to BS EN 14566:2008 and carry a Fire Classification of A1, so they meet the recognised standard for screws fixing plasterboard.