Shanti Tower
Which sections carry the deck and the swing, and which screws and bolts survive salt air.
Start with the span. At a 40 psf deck load, a 2x6 (38 x 140 mm) beam on 16 in (406 mm) centres covers about 2.9 m (9 ft 6 in) — enough for most platform frames without intermediate posts.
Swing loads rewrite that table. A swing in motion pulls the beam downward and sideways together, so any beam carrying hangers steps up to a 2x8 (38 x 184 mm). The pairing of beam and hanger is covered in Swing Hangers, Ladders and Post Anchors.
On narrow screens, swipe or scroll the plate sideways.
Decking boards are smaller than people expect: 19-25 mm thick and 90-140 mm wide, laid with a 6 mm (1/4 in) gap between boards. The gap drains rain off the platform and absorbs the boards' seasonal swelling — tight-laid outdoor decking buckles.
Then the metal. Outdoor fixings should be 304 stainless or hot-dip galvanised. Standard zinc-plated screws in coastal air corrode through in 1-2 years — the plating is a thin surface layer, and once salt air breaches it the screw goes quickly. If cars rust in your street, you are in coastal air.
Structural connections use bolts, not screws: posts anchor to their footings with 5/8 in (16 mm) galvanised anchor bolts, and swing hangers take 5/8 in eye bolts. The clearances this frame must respect are set out in Deck Height, Guardrails and the Use Zone.
Further reading