JavaScript seems to be disabled in your browser. For the best experience on our site, be sure to turn on Javascript in your browser.

FREE Delivery Australian OwnedSpend DISCOUNTS

Home
Screws for Decking
Screws only for Metal

Screws only for Metal

Screws only for Metal

Not sure what screw size you have or need?

Two ways to confirm before you order - whichever you already know.

1If you have a screw in hand

Measure across the outside of the thread - not the shank - to get the gauge (a 10g decking screw measures about 4.8mm). Screw gauges have a wider tolerance than bolts, so treat it as a close match rather than exact. Then measure the overall length, head included - decking screws are countersunk.

Open the screw gauge sizing chart ›

2If you know the gauge

Every product page carries a Screw Gauge and TPI chart for its range - every gauge links straight to the product. Coarse threads suit treated pine and softwood decking; fine threads suit hardwood boards like merbau and spotted gum.

T17 decking screw side profile showing where to measure

T17 type 17 point - gauge is measured across the thread.

Decking screws for metal are the specialist fastener for decking timber direct to steel joist. The bugle batten head reams a clean countersink in the decking timber and seats flush; the self drilling point drills through the steel joist below; the part-thread design allows the deck boards to pull tight to the joist without thread interference. One fastener completes the join without pre-drilling or two-stage fixing.

Also known as: Steel Joist Deck Screw, Bugle Batten Screw, In-Hex Deck Screw, Metal Joist Decking Screw.

14g-10 gauge with internal-Hex (5mm) drive, part-thread design. Bugle batten head for clean timber countersink. Coarse self drilling thread, Tek 3 drill point for steel joist up to 3.5mm thickness. Lengths from 50mm through 100mm cover decking thicknesses from 19mm through 45mm plus the steel joist plus engagement. Galvanised Class 3 finish.

GRADES AND MATERIALS

Zinc Yellow (Class 2): zinc plate with a yellow chromate passivation - Class 2 corrosion rating for interior and dry, sheltered work. Galvanised (Class 3, 4, B8 and X9): galvanised and heavy-coated finishes for exterior, structural and coastal exposure - the higher the class, the harsher the environment it suits. Both use a Class-rated steel core for high pull-out and shear strength.

DRIVE AND INSTALLATION

Drive with an internal-Hex 5mm bit in a powered driver at 1200-1800 RPM. The bugle batten head reams the timber face as the screw enters - keep the driver perpendicular to the deck board for a square countersink. The part-thread design means the upper unthreaded section passes freely through the board so the board pulls firmly to the joist below.

SIZE AND DRILL CAPACITY

14g-10 gauge, lengths 50mm (for 19mm board on 25mm joist), 75mm (for 32mm board on 50mm joist), 100mm (for 45mm board on 50mm joist). Match the length so 15-25mm of thread engagement extends below the joist - any less reduces pull-out, any more wastes screw length.

WHY AUSTRALIA TRUSTS BOLT & NUT

With 15+ years selling fasteners online from Brisbane, we hold over 25,000 stock lines and 200 million pieces - 98.75% of online orders placed before 1pm leave same day. Save more as you buy more - we offer up to 13 price breaks plus 3 spend-tier discounts. Read our customer reviews or get in touch if you need help picking the right decking-into-metal screw.

YOU'RE ON A SECURE SITE

Copyright © 2026 Bolt & Nut Australia Pty LTD, ABN 45 159 328 604

Magento Website built By dZine-Hub

Spend up to $99 5% Discount
Spend between $100 - $249 10% Discount
Spend $250 and above 15% Discount