Gyproc Drywall Screw 3.5 x 35 mm - Board to Metal (pack of 500)

• Manufacturer: Gyproc (Saint-Gobain)
• Product: Drywall screw — board to metal framework
• Size: 3.5 x 35 mm · Pack: 500 pieces
• Screwdriver bits supplied in the box
• Self-tapping with a countersunk cross-head
• Zinc plated steel — corrosion resistant
• 35 mm suits a double layer of 12.5 mm board on metal framing

Gyproc Drywall Screw 3.5 x 35 mm is the board-to-metal fixing for plasterboard onto a GI framework, supplied in a box of 500 with screwdriver bits included.

Length is the whole decision on a drywall screw, and it follows a simple rule: the screw must pass through the board and penetrate the steel by roughly 10 mm to grip properly. That gives a clean mapping across the range:

25 mm suits a single layer of 12.5 mm board. 35 mm — this one — suits a double layer of 12.5 mm board, which is 25 mm of board plus the penetration. 50 mm covers thicker build-ups and special cases. They are not interchangeable: order 35 mm for a single-layer ceiling and the screws stand proud inside the section for no benefit; order 25 mm for a double layer and they will not reach the steel at all.

These are self-tapping screws for metal framework — a fine thread and a sharp point that cut into GI sections. That matters because drywall screws come in two thread types that look almost identical in a box: board-to-metal, which these are, and board-to-wood, which has a coarse thread for timber. A coarse wood screw driven into a GI section spins without gripping or fails to pull the board tight, and you will not notice until the ceiling is up and moving.

The zinc plating is there for corrosion resistance, which matters more than it sounds: the screw heads sit under jointing compound and paint, and a corroding head stains through the finish months later.

Technical Specifications

Applications

1) Should I buy 25 mm, 35 mm or 50 mm?

It depends on your board build-up. The screw must pass through the board and penetrate the steel by about 10 mm. So: 25 mm for a single layer of 12.5 mm board, 35 mm for a double layer, and 50 mm for thicker build-ups. They are not interchangeable in either direction.

2) Are the screwdriver bits really included?

Yes — Gyproc supplies these with screwdriver bits in the box. Bits wear out with use, particularly when driving several hundred screws overhead, so having them included is genuinely useful rather than a token inclusion.

3) What is the difference between board-to-metal and board-to-wood screws?

The thread, and it decides whether the screw grips at all. Board to metal — these — are self-tapping with a fine thread that cuts into GI sections. Board to wood screws have a coarse thread for timber. They look almost identical in a box and are not interchangeable, so check which framing you have.

4) How deep should I drive them?

Just below the paper surface, without tearing the paper. The paper face carries the load — once the head breaks through it, the screw holds almost nothing, and that fixing will eventually show as a popped head through the finished ceiling. A depth-setting nosepiece stops the driver automatically and is far more reliable than judging depth by feel.

5) Why does the zinc plating matter?

Because of where the heads end up. They sit under jointing compound and paint, so a corroding screw head stains through the finish — and by then the ceiling is complete. The corrosion-resistant zinc plating prevents that in normal internal use.

1. Return within 24 hours of delivery for:
   • Damaged or defective product
   • Wrong or missing item
2. Product cannot be returned once installed or used
3. Refer to Refund Policy for complete details