Repair Systems — 03 — Facade & External Envelope
Cladding Fixing & Anchor Systems — Stainless Grade 316
Technical product reference for stainless grade 316 cladding fixing and anchor systems — self-drilling screws, hex-head bolts, and chemical anchors for securing cladding panels and subframes to concrete, masonry, and steel framing. All-zone suitable including coastal and marine.
What are stainless 316 cladding fixing and anchor systems?
Stainless steel 316 fixing and anchor systems are the fastener schedule for Australian cladding construction in coastal, marine-adjacent, and high-corrosion environments. They encompass self-drilling screws for panel-to-rail connections, chemical anchors for post-installed bracket-to-concrete connections, and mechanical expansion anchors for uncracked concrete. All are required to be HCR class per AS 3566 or equivalent in coastal zones.
Product Reference
4 product systems — SS316 fixings and anchors — scroll to view all
Buildex SS316 Self-Drilling Screw — FC-to-Aluminium
Self-Drilling Screw — SS316 — FC-to-aluminium fixing
System Description
Buildex 316 stainless self-drilling screws are the standard fixing for FC sheet and FC panel to aluminium top-hat subframe in Australian cladding construction. The self-drilling tip eliminates pre-drilling through the FC panel — reducing installation time and risk of panel cracking near fixing points. The 316 stainless shank provides HCR (high corrosion resistance) class rating per AS 3566, suitable for coastal and marine-adjacent applications. Available in Torx drive to reduce cam-out and drive force at depth. The FC panel must be pre-drilled to the correct clearance hole size so the screw passes freely through the panel and threads only into the aluminium rail.
Technical Properties
- Material: 316 stainless steel — AISI 316 — HCR class per AS 3566
- Drive: Torx (TX25 or TX30) or hex head — reduces cam-out at depth
- Thread: Hi-Lo thread optimised for FC and fibre substrate grip in aluminium
Limitations
- Not suitable for fixing into concrete or masonry — self-drilling only into steel and aluminium
- FC panel must be pre-drilled to correct clearance hole size — screw passes through, threads into rail only
- Overtorquing cracks FC panel — use torque-limited driver and follow manufacturer's installation instructions
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Hilti HIT-Z SS316 Chemical Anchor — Cladding Bracket to Concrete
Chemical Anchor — SS316 — post-installed bracket to concrete
System Description
Hilti HIT-Z 316 stainless chemical anchors are the preferred post-installed anchor for cladding bracket connections to concrete and masonry in remediation projects. The chemical injection capsule system provides predictable load transfer and can be installed in both cracked and uncracked concrete. All designs must be carried out using Hilti PROFIS Anchor software and verified by a structural engineer — the software generates an anchor design report accepted by certifiers. Pull-out testing of representative installed anchors is required on all high-rise remediation projects per AS 3600. Adhesive: Hilti HIT-RE 500 V4 or HIT-HY 270 depending on substrate condition and design load.
Technical Properties
- Material: 316 stainless threaded rod — ISO metric — corrosion resistant in coastal and marine zones
- Rod diameters: M10, M12, M16 standard — embedment engineered per PROFIS Anchor output
- Adhesive: Hilti HIT-RE 500 V4 or HIT-HY 270 — confirmed per substrate and load requirement
Limitations
- Engineer must produce PROFIS Anchor design report — no rule-of-thumb spacing or embedment
- Hole must be core-drilled and cleaned — dust blown twice — adhesive failure if dusty or wet
- Full cure required before bracket loading — minimum 24 hr at 15°C — cannot be rushed
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Bi-Metal Drill Screw SS316 — FC Panel to Thick Steel Subframe
Bi-Metal Self-Drilling Screw — SS316 shank / carbon tip
System Description
Bi-metal self-drilling screws combine a 316 stainless steel shank (for corrosion resistance) with a hardened carbon steel drill tip (for drilling capacity through thick steel subframe members). Standard 316 self-drilling screws cannot penetrate steel gauge above approximately 1.6 mm — bi-metal fasteners extend this to 4–8 mm steel, covering RHS, SHS, and heavy-gauge steel stud framing used in commercial cladding subframes. The carbon steel tip is enclosed within the stainless shank geometry and does not contact the exterior environment after full installation. A pilot clearance hole through the FC panel is required before applying the screw — the drill tip is for penetrating the steel rail only.
Technical Properties
- Shank: 316 stainless steel — HCR rated per AS 3566 — corrosion resistant
- Tip: hardened carbon steel — self-sacrificing during drill-through of steel
- Drilling capacity: up to 8 mm steel in single pass — suits RHS and SHS subframe
Limitations
- Carbon steel tip will corrode if exposed — ensure tip is fully embedded in steel after installation
- Bi-metal tip is consumed during drilling — cannot re-use or re-drive the same fastener
- Not suitable for fixing into concrete or masonry — for steel subframe only
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Hilti KB-TZ2 SS316 Mechanical Expansion Anchor — Post-Installed Concrete
Mechanical Expansion Anchor — SS316 — uncracked concrete
System Description
The Hilti KB-TZ2 is a torque-controlled expansion anchor in 316 stainless steel, used for post-installed anchor connections into uncracked concrete where chemical adhesive anchors are impractical — for example in tight overhead spaces, wet holes, or applications requiring immediate load after installation. The anchor expands mechanically as it is torqued to the specified installation torque — no adhesive cure time required. Full Hilti PROFIS Anchor design is required for all structural connections. Pull-out testing of representative installed anchors is mandatory on high-rise cladding remediation projects. Suitable only for uncracked concrete — use HIT-Z chemical anchor for cracked zones.
Technical Properties
- Material: 316 stainless steel — coastal and marine zone rated
- Type: torque-controlled expansion (TCE) anchor — immediate load after torquing
- Diameters: M8, M10, M12, M16 — embedment per PROFIS Anchor design output
Limitations
- Not suitable for cracked concrete — use Hilti HIT-Z chemical anchor for cracked zones
- Concrete must be structurally sound and uncracked — confirm with survey before specifying
- Minimum edge and spacing distances are large — check layout against anchor plan before drilling
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of SS316 cladding fixing and anchor systems. Confirm all product selections against the current manufacturer TDS before specifying.
| Product system | Brand | Fixing type | Material | Substrate | Coastal | Engineer req. | Primary use |
|---|---|---|---|---|---|---|---|
| Buildex SS316 Self-Drilling | Buildex / ITW | Self-drilling screw | 316 Stainless Steel | Aluminium / light steel rail | Yes — HCR rated | No | FC panel to aluminium top-hat rail |
| Hilti HIT-Z Chemical Anchor | Hilti Australia | Chemical injection anchor | 316 Stainless threaded rod | Concrete / masonry | Yes | Yes — PROFIS Anchor | Cladding bracket to existing concrete |
| Bi-Metal SS316 Drill Screw | Buildex / ITW | Bi-metal self-drilling | 316 SS shank / carbon tip | Steel 4–8 mm | Yes — HCR rated | No | FC panel to thick steel subframe |
| Hilti KB-TZ2 Mechanical | Hilti Australia | Torque-controlled expansion | 316 Stainless Steel | Uncracked concrete | Yes | Yes — PROFIS Anchor | Bracket to concrete — no cure time required |
Do not confuse stainless 316 cladding fixings with:
- Grade 304 stainless fixings — lower corrosion resistance than 316; 304 is insufficient in coastal or marine-zone facade applications where chloride exposure requires the molybdenum content found in grade 316 — using 304 instead of 316 in these zones risks early fastener corrosion and cladding detachment
- Galvanised steel screws or bolts — zinc coating is incompatible with aluminium subframes (bimetallic corrosion) and insufficient for direct coastal or marine zone exposure; galvanised fixings must not be used to fix aluminium cladding or subframe components
- Carbon steel or black steel screws — no corrosion protection; never suitable for external facade fixing in any climatic zone — will corrode and fail rapidly on an exposed building facade
- Aluminium blind rivets used as structural load-transfer anchors — aluminium rivets are used for panel-to-subframe secondary fixing, not for anchoring the subframe to the building structure; structural load transfer requires engineered anchors with certified pull-out and shear capacity
Disclaimer
Information is general only. Fixing selection and spacing must be confirmed by a structural engineer against design wind loads. Site pull-out testing is mandatory for anchors into existing concrete or masonry. Do not rely on this reference as a substitute for professional engineering advice.