Self-Drilling Screws
Hex Washer Head Self-Drilling Screw with EPDM Washer
DIN 7504K indented hex washer head roofing screw with bonded EPDM washer, ST4.2–ST6.3, drill points #1–#5.
DIN 7504 KST4.2
Self-Drilling Screws
A self-drilling screw carries its own drill bit at the tip, so it cuts the pilot hole, forms the thread and clamps the joint in a single operation. We cold-head C1022 carbon steel, case-harden it to 530 HV or higher, and finish it to suit roofing, cladding, steel framing and sandwich-panel work.
Self-Drilling Screws
Hex Flange Head Self-Drilling Screw
Galvanised hex flange head Tek screw with integral serrated flange, for steel-to-steel framing and cladding.
ST3.5–ST6.3Carbon steel
Self-Drilling Screws
Colour Painted Hex Head Roofing Screw
Self-drilling roofing screws with heads powder-painted to match RAL and Colorbond sheet colours.
DIN 7504 KST4.8
Self-Drilling Screws
Sandwich Panel Self-Drilling Screw
Long hex washer head screws with a secondary thread to clamp insulated sandwich panels to steel purlins.
ST5.5C1022 steel
Self-Drilling Screws
Wafer Head (Modified Truss) Self-Drilling Screw
Low-profile wafer head Tek screw, Phillips drive, for fixing sheet to steel studs without a raised head.
ST4.2C1022 steel
Self-Drilling Screws
Flat Head Self-Drilling Screw with Wings
Countersunk reamer screw: wings ream a clearance hole in timber, then snap off on the steel.
DIN 7504 PST4.2
Self-Drilling Screws
SS316 (A4) Hex Washer Head Self-Drilling Screw
Marine-grade 316 stainless hex washer head screw to DIN 7504K, 20–100 mm, for thin steel and aluminium near the sea.
DIN 7504 K#10–#14
Self-Drilling Screws
Type 17 Roofing Screw, AS 3566 Class 3
#12-11 × 75 mm hex flange Type 17 timber roofing screw, ceramic coated 1,000 h, pre-assembled EPDM washer.
AS 3566.2 Class 3#12-11 × 75 mm
Buying guide
How to specify self-drilling screws
Three decisions that prevent most problems on site.
Match the drill point to the steel
Point #1 suits sheet up to 0.9 mm, #2 up to 2.8 mm, #3 up to 4.4 mm, #4 up to 5.25 mm and #5 up to 12.5 mm. The drill flute must clear the full material thickness before the thread engages, or the screw will jam and snap.
Choose a washer for weather-tight joints
Roofing and cladding screws take a bonded EPDM washer (14, 16 or 19 mm) under an indented hex washer head. The rubber seals the hole; the steel backing spreads the load so the sheet does not dimple.
Specify corrosion class, not just "zinc"
Electro-zinc gives roughly 72 h to white rust in salt spray. For exterior roofing ask for ceramic coating (500–1,000 h) or AS 3566 Class 3/4 coatings, and for coastal sites move to bi-metal stainless screws.
Applications
Projects using self-drilling screws
Steel warehouse with sandwich panel roof and walls
Long self-drilling screws for 100–150 mm insulated panels on hot-rolled purlins in a hot, dusty climate.
Hardwood decking and timber structures
Corrosion-resistant timber screws that will not stain tannin-rich hardwood or split board ends.
Coastal facade and aluminium cladding
A4 stainless and bi-metal fixings for facades within a few kilometres of salt water.
Self-Drilling Screws: common questions
What is the difference between self-drilling and self-tapping screws?
A self-tapping screw forms threads in a pre-drilled hole, while a self-drilling screw drills its own hole first using a drill-shaped point. Self-drilling screws save a step on metal-to-metal joints.
Which standards do your self-drilling screws follow?
We produce to DIN 7504 (K, M, N, P, O forms), ISO 15480–15483 and AS 3566.1/.2, and to customer drawings for non-standard lengths, heads or head marks.
What is your MOQ for self-drilling screws?
Standard sizes start at about 500 kg or 50,000 pieces per size. Mixed sizes can share one container, and stock items can ship in smaller lots.
Request for quotation
Quote for self-drilling screws
Tell us the screw, size and quantity. A sales engineer replies within one business day with price, lead time and a sample offer.
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