15m × 6m Floating Deck | TreadTech Aluminium Deck Framing System | TreadJack Pedestals
Modern architecture increasingly blurs the line between indoor comfort and outdoor freedom - and nowhere is this more evident than on the Kāpiti Coast, where open coastal vistas call for high-performing, resilient construction solutions.
This case study showcases how the TreadTech Aluminium Deck Framing System, TreadJack Adjustable Pedestals, and a UNEX Panorama Frameless Glass Balustrade were used together to deliver a stable, compliant and architecturally refined floating deck in a high-seismic coastal environment.
Installed by The Complete Building Company and Provista Balustrade Systems, the result is a clean, modern outdoor living space that protects the building envelope and provides uninterrupted ocean views.
A Modern Floating Deck Built for Coastal Conditions
The homeowner wanted a large, low-maintenance outdoor area that felt connected to the home while maximising the coastal outlook. With no ability to fix the structure back to the building due to waterproofing and architectural constraints, a floating deck system was the only viable solution.
The TreadTech Aluminium Deck Framing System was selected for its:
Long-span strength and stability
Engineered load capacity for balustrades, decking and foot traffic
Durability in harsh coastal environments
Compatibility with timber and composite planking, tiles, or pavers
Lightweight components ideal for rooftop or membrane installations
Supported by TreadJack Pedestals, the system provided a perfectly level, adjustable platform while keeping all penetrations off the waterproofing membrane.
Engineering Challenges - and How the Team Solved Them
Building in the Wellington region adds another layer of complexity: extremely high seismic coefficients.
To ensure the floating deck remained safe and code-compliant, the UNEX engineering team worked collaboratively with the architect, builder, building engineer, and waterproofing supplier Viking Roofspec.
No Fixing Back to the Building Allowed
Architectural and waterproofing constraints meant the deck could not be connected to the building.
Solution: A site-specific PS1 was developed, with the aluminium framing designed to act fully independently.
Floating Structure with No Front Upstands
The front edge of the deck had no upstands to provide bracing or lateral restraint.
Solution: UNEX created a custom clamping/boxed aluminium section around the new upstands, providing controlled lateral movement during seismic events.
Preventing Overturning from Balustrade Loads
The frameless balustrade required significant resistance at its base.
Solution: Viking RoofSpec RoofTrak® waterproof fixing brackets were integrated directly into the TreadTech frame to resist overturning forces without compromising the membrane.Site-Specific PS1 for Compliance
A project of this scale and complexity required a dedicated engineering pathway.
Solution: UNEX produced a site-specific PS1 tailored to the geometry, seismic zone, and waterproofing constraints of the Kāpiti Coast site.
TreadTech + UNEX Balustrades - Site Specific Design
Where innovation meets performance, UNEX brings together the precision of our balustrade systems with the engineered strength of the TreadTech Aluminium Deck Framing System.
Designed for contemporary floating deck applications, this combined solution can be delivered as a site-specific design, supported by a site-specific PS1 to address complex project conditions such as high seismic zones, membrane-only substrates, limited fixing opportunities, or bespoke architectural requirements.
This integrated approach delivers a cleaner aesthetic, preserves membrane integrity, and reduces material use - all while maintaining full compliance, durability, and structural performance.
Key Benefits
✔ Protects waterproofing
Reduced substrate fixings minimise risk to membranes or cladding.
✔ Single-source accountability
One supplier for both systems simplifies coordination and PS1 documentation.
✔ Speeds up installation
An engineered, fully compatible package reduces on-site resolution time.
The result is a sleek, architecturally resolved outdoor solution - ideal for coastal, rooftop or high-seismic applications.
The deck features UNEX Panorama Frameless Glass Balustrades mounted in a continuous fixing channel recessed into the TreadTech framing.
This created:
A clean, minimalist finish
Uninterrupted ocean views
A fully engineered interface between balustrade loads and the floating deck frame
Installed by Provista Balustrade Systems, the balustrade system complements the open coastal design while meeting all NZ Building Code requirements.
A Sophisticated, Highly Durable Outdoor Living Space
Thanks to smart collaboration between all parties, the finished result is a robust, visually striking floating deck that:
Can withstand harsh coastal winds
Meets stringent Wellington seismic requirements
Protects membrane integrity
Provides a stable, long-lasting platform for outdoor living
Delivers premium aesthetics with its frameless glass finish
Perched above the Kāpiti coastline, this new outdoor living space is a strong example of how TreadTech transforms complex sites into functional, compliant and architecturally refined environments.
