Six aluminium joist profiles from 50mm to 90mm depth. Pre-cut service. Full span tables. BBA-certified. Every profile designed to work with every AliDeck board.
Joist feet fix to the structural substrate — steel or concrete — using M10 anchor bolts. Adjustable feet allow ±50mm height adjustment to manage substrate tolerances and deck falls.
Joists are laid at specified centres — typically 400mm or 500mm — determined by the board profile and loading. Cross-members connect the grid at perimeters and at board joints.
AliDeck boards clip-fix to the joist top face using concealed stainless fixings. No visible fasteners on the deck surface. All profiles compatible with all joist types.
| Profile | Depth | Spacing | 1.5 kN/m² | 3.0 kN/m² | 5.0 kN/m² |
|---|---|---|---|---|---|
| J50 Junior | 50 mm | 400 mm | 2.1 m | 1.8 m | 1.4 m |
| J70 Senior | 70 mm | 400 mm | 3.0 m | 2.4 m | 1.9 m |
| J70P Senior Plus | 70 mm | 500 mm | 3.6 m | 3.0 m | 2.4 m |
| J90 Heavy Duty | 90 mm | 500 mm | 4.5 m | 3.6 m | 2.8 m |
| J90P HD Plus | 90 mm | 600 mm | 5.0 m | 4.5 m | 3.5 m |
| J50W Wide | 50 mm | 400 mm | 1.8 m | 1.5 m | 1.2 m |
Span values are indicative. Final specification must be confirmed by AliDeck technical team based on project loading and substrate.
The joist system is just one layer. Explore the full AliDeck system — boards, drainage, balustrades, and cladding. One contact, one spec.
