Which Screw is Best for your Deck?

To complement Barwon Timbers extensive range of beautiful decking timbers, our Hardware department carries a wide range of decking screws to suit all situations. 

To help you select the right decking screw, here is our suggestion based on various board widths:

Board WidthScrew GaugeSpacing between Boards
70mm – 90mm7-10G4-6mm
90mm – 120mm10-12G5-8mm

These suggestions are a guide only and we recommend visiting our Hardware store to view our range of decking screws.

When selecting a decking screw, keep in mind that there are various finishes available depending on the application and environmental conditions.

These finishes include:


Galvanising is a standard coating for many building screws. The screws are usually dipped and coated in a sacrificial zinc coating that prevents the screw itself from corroding. Galvanised screws can be a cost-effective option in non-marine/non-swimming pool areas and for those who prefer a less bright finish on larger gauge screws.


Synthetic coatings such as Chemshield are another cost-effective option, and less obtrusive for narrower boards. The Chemshield range comes in a brown tone specifically designed for decking with narrower heads to suit around 90mm board widths. These screws have been a popular choice for customers maintaining colour in their decks using our coating products rather than letting the timber silver off over time.

Another coating product option is the Bremick Revolution B8 coating, guaranteed four times stronger than galvanised and rated up to Very Severe Marine conditions. The strong, satin finish coating resists bleeding and the decking range has a screw to suit any board width. Both finishes are compatible with treated pine.


Stainless steel decking screws remain a popular choice. We stock both 304 and 316 stainless screws.

304 Stainless Steel Screws

304 Stainless Steel is the most popular choice for general environments, providing a bright finish for the long term.

Barwon Timber is a stockist of AnchorMark’s Decking Screws. These screws are popular with our trade customers, largely owing to the performance of the screws.

Barwon Timber also stocks the SPAX range of decking screws. SPAX decking screws are designed to allow for no pre-drilling in some timbers. With their quicker install time, you are unlikely to get splitting in timber during installation.

316 Stainless Steel Screws

In severe and marine applications, 316 stainless steel is the recommendation to resist tarnish and corrosion, which can compromise the integrity of your new deck long term.

To see our range of decking screws, come into our Hardware store. Our Hardware team are happy to discuss what the best screw will be for your timber decking project.

Anchormark’s Timber to Metal 316 Stainless Steel Decking Screw.
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Barwon Blogger


  1. Toni on June 2, 2015 at 18:51

    Don’t recommend Bremick B8 – they rusted in our deck after two weeks and they are doing everything they can not to warrant their screws.

    • Barwon Blogger on June 5, 2015 at 14:55

      We are sorry you have had a problem with the B8 coating and we are happy to contact Bremick to follow up. We have had a lot of B8 screws successfully installed and performing as we would expect.

      Recommending a decking screw can be difficult thing given there are a number of different conditions that will affect your choice.
      – What width and thickness is the deck board?
      – What geographical location is the deck?
      – Coastal, around a swimming pool, under cover?

      A popular option is to over specify the screws and use a heavy gauge screw in stainless steel, this will help to give peace of mind and avoid costly re-work.

      Another common problem that has been an issue for screw manufacturers is customers using harsh chemical deck washes that affect the coating on the screws, causing rust on the screw heads.

      The best outcome will be achieved by talking to your supplier about ALL of the specifics relating to your job and working toward an outcome that satisfies both your aesthetic appeal and budget. We are happy to help out, please give us a call.

  2. Andrew on November 23, 2015 at 19:47

    We are building a deck with 136mm wide spotted gum. Someone said 12g screws would be ok and the head is only a little smaller than 14g. The 14g is harder to install. What do you think?

    • Barwon Blogger on November 24, 2015 at 08:37

      Hi Andrew,

      We suggest visiting our hardware store and having a look at our range of fixings and letting us know what type of decking and joists you are using.

      You can also find more online decking information at the Timber Merchants Association website: https://timber.asn.au/


  3. Clynt on March 20, 2017 at 08:54

    My builder son just finished building a deck for me (in Sydney) using Bremick B8 screws. After a couple of days of the recent heavy rain, the screw heads were covered in rust. We are contemplating extracting all the screws and replacing them with galvanized screws. Tony (above), on 2 June 2015, posted about his similar problem. Have others had this experience?

  4. Mat on January 26, 2018 at 07:53

    I want to save $ and use dipped treated pine screws on a h3 joist with 90 mm merbau decking I always use stainless. Are these dipped treated screws appropriate

  5. Vangeli on March 12, 2018 at 20:10

    Mechanical damage to the head during installation is also a common cause of rust to these coated screws. I’ve seen it with galvanising where 1 screw would be in excellent condition and the screw next to it would be fully rusted. Remember the coating is only very thin, and the something simple as using an incorrectly sized driver can damage these heads easily. (not saying that the problems in these cases, but just one of many things that can happen with these coated screws.)

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