Decking Screw Calculator

• Meets BPIR regulation
• 316 stainless
• The highest performing self-drilling screw.
• Star Drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Pre-drilling generally not required depending on timber and driver (except on board ends).

Applications

• Commonly used for hardwood up to 21mm thick
• Tips for use: Use T20 Max Torsion tip to drive screw.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Star drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Pre-drilling generally not required depending on timber and driver (except on board ends).

Applications

• Commonly used for hardwood up to 21mm thick
• Tips for use: Use T20 Max Torsion tip to drive screw.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Star drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Pre-drilling generally not required depending on timber and driver (except on board ends).

Applications

• Commonly used for hardwood up to 21mm thick
• Tips for use: Use T20 Max Torsion tip to drive screw.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Star drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Pre-drilling generally not required depending on timber and driver (except on board ends).
• Timber is protected from tearing or splitting by the drill tip.
• The self-drilling tip makes the installation quick and easy.
• Small head diameter ensures that the head can sink in cleanly and easily.
• Grooved shank adds extreme holding-down strength.
• Available with three different finishes A) stainless, B) silicone bronze vintage, and C) black coated.
• Smooth head for a perfect barefoot proof finish.

Applications

• Commonly used for hardwood up to 21mm thick and also composite decking
• Decking and cladding to timber substructures.
• Designed especially for hardwood usage.
• Tips for use:
• Use T20 Max Torsion tip to drive screw.

Building Materials

• Merbau
• Spotted Gum
• Blackbutt
• Tallowwood
• Stringybark
• Karri
• Sydney Bluegum
• Jarrah
• Ironbark
• Tasmanian Oak
• Victorian Ash
• Grey Box
• Oak

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in some high tannin timbers such as Garapa may cause localised tannin stains on the surface of the timber. This risk is reduced by using 316 stainless steel screws (and not 304 stainless steel) and using un-coloured screws (not bronze or black stainless steel options).

Bronze finish is a 'vintage' look and may wear off when installed in high traffic areas, cleaned with abrasive methods or damaged during installation.

Functionality

• Use T20 Max Torsion tip to drive screw.
• SIT® Drive Head: Ensures optimal torque, fast centering, and a snug fit.
• Aggressive Shank: Provides strong grip with reduced drive-in torque—ideal for hardwood without snapping.
• Asymmetrical Thread: Lowers setting torque for easier installation and up to 30% faster screwing with anti-friction coating.
• Pyramid Tip: Minimises timber splitting and speeds up drilling—perfect for hardwood decking and cladding.
• 316 Stainless Steel: Offering high corrosion resistance to reduce the chance of tea-staining and rust, increased fracture torque, and suitability for outdoor and close to water applications.

For best results, we recommend pre-drilling and pre-countersinking holes.

Pre-drilling may be necessary in extremely hard timbers.

For highly corrosive environments, we recommend the use of the 316 Stainless Steel coloured screw only (not vintage or black coated).

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Star drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Pre-drilling is required but this means driving in the screws is easier on tools and gives a longer battery life than the self drilling type.

Applications

• Commonly used for hardwood up to 21mm thick
• Tips for use: Use T20 Max Torsion tip to drive screw.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in some high tannin timbers such as Garapa may cause localised tannin stains on the surface of the timber. This risk is reduced by using 316 stainless steel screws (and not 304 stainless steel) and using un-coloured screws (not bronze or black stainless steel options).

Bronze finish is a 'vintage' look and may wear off when installed in high traffic areas, cleaned with abrasive methods or damaged during installation.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Flush finish.
• Star Drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.

Applications

• Commonly used for both hardwood and softwood decking.
• Tips for use:
• Use 10g Quick Cut for counter sinking/drilling pilot hole.
• T25 High Torque tip to drive screw.
• Pre-drilling may be required and recommended for hardwood and board ends.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Stainless Steel Decking Screws

• Meets BPIR regulation
• 316 stainless
• Flush finish.
• Larger head to reduce pull-through on larger softwood boards which may experience more movement.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.

Applications

• Commonly used for both soft and hardwood wide board decking up to 30mm thick.

Tips for use

• Use Quick Cut for counter sinking/ drilling pilot hole. 4mm Max Torsion tip to drive screw.
• Pre-drilling may be required and recommended for hardwood and board ends.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Flush finish.
• Larger head to reduce pull-through on larger softwood boards which may experience more movement.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.

Applications

• Commonly used for both soft and hardwood wide board decking up to 30mm thick.

Tips for use

• Use Quick Cut for counter sinking/ drilling pilot hole. 4mm Max Torsion tip to drive screw.
• Pre-drilling may be required and recommended for hardwood and board ends.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Flush finish.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Star drive allows for greater torque
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.

Applications

• Commonly used for soft and hardwood wide board decking up to 30 mm thick.

Tips for use

• Use Quick Cut for counter sinking/ drilling pilot hole. Use 4mm Max Torsion tip to drive screw.
• Pre-drilling may be required and recommended for hardwood and board ends.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Star Drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Pre-drilling is required but this means driving in the screws is easier on tools and gives a longer battery life than the self drilling type.

Applications

• Commonly used for hardwood decking up to 21mm thick
• Tips for use: Use T20 Max Torsion tip to drive screw.
• Pre-drilling at board ends is required.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Star Drive allows for greater torque.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.
• Pre-drilling is required but this means driving in the screws is easier on tools and gives a longer battery life than the self drilling type.

Applications

• Commonly used for hardwood decking up to 21mm thick
• Tips for use: Use T25 Max Torsion tip to drive screw.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless
• Flush finish.
• Heavy duty screw with an industrial look.
• High pull out loads.
• Heads look uniform across screws, unlike Square Drive heads which need to be lined up to achieve a uniform look.

Applications

• Commonly used for both soft and hardwood wide board decking up to 65mm thick.

Tips for use:

• Use Quick Cut for counter sinking/drilling pilot hole.
• 5mm Max Torsion tip to drive screw.
• Pre-drilling may be required and recommended for hardwood and board ends.

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Stainless Steel Decking Screws

• TX six lobe drive for optimum steering and power transmission
• Reinforced head prevents breakaway during countersinking in hard materials
• Ribs under the head make countersinking needless and allow for a plane and easy milling
• Self cutting point for fast and neat fixings

Stainless steel 1.4529 is known for its exceptional performance in demanding environments, making it a reliable choice for building and industrial applications.

• High resistance to localised corrosion, including crevice corrosion, pitting, and chlorine‑induced stress corrosion cracking.
• Excellent mechanical properties, maintaining strength and stability across a wide temperature range.
• Strong resilience in chemical environments, offering superior resistance when exposed to sulphuric acid, phosphoric acid, chlorides, and various salts.
• High wear resistance, ensuring durability and long service life in tough conditions.
• Stainless steel grade 1.4529 meets the EU Standards (EN 13451) for use above indoor swimming pools and in tunnels.

At Anzor, we supply some of the world’s most advanced stainless steels. These grades are engineered for superior strength, corrosion resistance, and long-term performance in the toughest environments — from marine to coastal construction and aerospace applications.  When a Stainless Steel Grade has a Pitting Resistance Equivalent Number (PREN) over 40, it is a 'SUPER' grade and should be fully resistant to localised corrosion (pitting/crevice corrosion) when immersed in seawater.  These grades are not only 'SUPER' in terms of corrosion resistance, but many items in our Anzor stock are also 'SUPER' in terms of strength and ductility (see Bumax DX129).

Indoor swimming pools are very different from outdoor swimming pools, and even seawater – they are among the most corrosive environments to be found. The issue does not arise from direct contact with the pool water, but from exposure to the corrosive environment in the air above it. Elevated temperatures, high humidity, and chemicals in aerosol form, especially chlorine compounds, create highly aggressive conditions.

In this environment, grades of stainless steel like 304, 316 and even 2205 can suffer stress corrosion cracking (which is hard to detect), especially when these components are under load.

A fatal pool roof collapse in the early 1990s in Europe was due to stress corrosion cracking of 304 stainless steel roof supports.  Following testing, the report suggested that 6% Mo alloys would not crack and subsequently the EU standard EN 13451 was created, which calls for stainless steel grades such as 1.4529 being used above indoor swimming pools for load bearing, safety critical components which are not regularly cleaned and exposed to indoor swimming pool environment.

Stainless steel grade 1.4529 is known for its exceptional performance in demanding environments, offering high resistance to localised corrosion, including crevice corrosion, pitting, and chlorine‑induced stress‑corrosion cracking, making it a reliable choice for building and industrial applications.

Click here to check CRC - Corrosion Resistance Classes

Areas of application for 1.4529

• Shipbuilding
• Offshore technology
• Swimming pool technology
• Plants in the chemical industry
• Condenser tubes and piping in power plants with heavily contaminated cooling water
• Heat exchangers and evaporators
• Flue gas desulphurization plants
• Bleaching system in the paper industry
• Tunnel construction
• Crystallization plants in salt production
• Tanks for aggressive chemical products
• Fire extinguishing systems
• and many more

1.4529 - Super Austenitic

Material 1.4529, also known as Alloy 926, is an austenitic special steel with a higher corrosion resistance than conventional chrome-nickel steel. Alloy 926 represents an enhancement to Alloy 904L (1.4539) stainless steel, with a raised molybdenum content and additional nitrogen. For this reason, the material is classified in the highest corrosion resistance class, CRC V.

• Tensile Strength Comparison Chart
• Click here to check CRC - Corrosion Resistance Classes
• Pitting Resistance Equivalent Number (PREN)

• Meets BPIR regulation
• 316 stainless steel with additional zinc coated steel tip offers a high degree of weather resistance.
• Self drilling tip makes the installation quick and easy.
• Small head diameter ensures that the head can sink in cleanly and easily.
• Smooth head for a perfect barefoot proof finish.

Applications

• Decking and cladding to steel substructures
• Self- drill decking screw
• Timber thickness up to 26mm
• Steel under construction 1.25-3mm.
• Tips for Use: Use T20 Max Torsion tip to drive screw.

Building Materials

• Merbau
• Spotted Gum
• Blackbutt
• Tallowwood
• Stringybark
• Karri
• Sydney Bluegum
• Jarrah
• Ironbark
• Tasmanian Oak
• Victorian Ash
• Grey Box
• Oak

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in some high tannin timbers such as Garapa may cause localised tannin stains on the surface of the timber. This risk is reduced by using 316 stainless steel screws (and not 304 stainless steel) and using un-coloured screws (not bronze or black stainless steel options).

Bronze finish is a 'vintage' look and may wear off when installed in high traffic areas, cleaned with abrasive methods or damaged during installation.

Functionality

• The SIT® drive (TX compatible) allows for optimum torque transmission, a tight and snug fit, and fast centering.
• The high efficiency thread with anti-friction coating to reduce drive-in torque.
• An aggressive drilling tip with wings cuts a clearance hole for decks with a steel under construction. It allows quick, easy and safe work without pre-drilling for steel thickness: 1.25 – 3.0 mm.
• The stainless steel grade of the screws (316) with an additional zinc coated tip gives them a high corrosion and weather resistance, increased fracture torque, and makes them suitable for outdoor use and close to water applications.
• INSTRUCTIONS FOR USE
• Drive in the fastener with high to maximum speed using a cordless drill or electric drill. As soon as you hit the metal substructure, reduce speed and increase the pressure slightly. Make sure you don’t overdrive the fastener by stopping as soon as the screw head is levelled with the surface.
• Only to be used with a drill driver (cordless or corded) / Do not use an impact driver

Click here to check the different types of decking screws and their use.

Anzor Stainless Steel Decking Screw Brochure

• Meets BPIR regulation
• 316 stainless steel offers a high degree of weather and galvanic resistance
• The self drilling tip makes the installation quick and easy
• Small head diameter ensures that the head can sink in cleanly and easily
• Timber is protected from tearing or splitting by the drill tip
• Smooth head for a perfect barefoot proof finish.

Applications

• Decking and cladding to steel substructures
• Self- drill decking screw
• Timber thickness up to 26mm
• Steel under construction 1.25-3mm.
• Tips for Use: Use T20 Max Torsion tip to drive screw.

Building Materials

• Merbau
• Spotted Gum
• Blackbutt
• Tallowwood
• Stringybark
• Karri
• Sydney Bluegum
• Jarrah
• Ironbark
• Tasmanian Oak
• Victorian Ash
• Grey Box
• Oak

Note: Screw length depends on the thickness and type of the material you’re working with. Consult a Licensed Building Practitioner (LBP) to determine the best screw length for your application.

NB: These guidelines should be read in conjunction with the New Zealand Building Code (NZS3602, NZS3604, NZS3605, NZS3640 and NZS4203).

Note: Stainless steel fasteners embedded in high-tannin timbers such as Garapa may cause localised tannin staining on the timber surface. This risk is reduced by using 316 stainless steel screws (rather than 304) and un-coloured screws (rather than bronze or black stainless steel options).

Bronze finish provides a ‘vintage’ look and may wear off in high-traffic areas, with abrasive cleaning, or if damaged during installation.

NB: This information is a guide only. Product selection and installation are the customer’s responsibility, taking into account all specific factors, including timber type and environment. Anzor accepts no liability for the application of this information.

Functionality

• The SIT® drive (TX compatible) allows for optimum torque transmission, a tight and snug fit, and fast centering.
• The high efficiency thread with anti-friction coating reduces the drive-in torque.
• An aggressive drilling tip with wings, cuts a clearance hole for decks with an aluminium under construction. It allows quick, easy and safe work without pre-drilling for aluminium thickness: 1.6 – 3.0 mm.
• The stainless steel grade of the screws (316) gives them a high corrosion and weather resistance, increased fracture torque, and makes them suitable for outdoor use and close to water applications.

Installation Instructions

Anzor Stainless Steel Decking Screw Brochure