Timber decking in Bali: installation and restoration

Species choice comes with a real trade-off, and we would rather explain it than sell it. Bengkirai is the value option — dense, locally available, silvers quickly and wants oiling twice a year. Merbau is more stable and darker, but it bleeds tannin onto pale stone for the first few months. Ulin, Bornean ironwood, lasts decades untreated and is priced accordingly, with sourcing that needs checking. Composite removes the oiling entirely and gets hot in afternoon sun.

Underneath, the build-up decides the lifespan. Frames are set clear of the ground on adjustable pedestals or galvanised shoes, never straight onto soil. Every member is treated before it is installed. Boards are spaced for drainage and airflow rather than butted tight for the photograph. Fixings are stainless within reach of salt air, because galvanised screws bleed rust streaks down a deck inside a year — and hidden clips go in where the surface should stay clean.

Why decks fail here, and it is rarely the timber

Lift a failed Bali deck and the story repeats. Joists laid on the ground or on a slab with no gap, so the underside never dries and rots from below while the top still looks presentable. Boards butted tight because it photographed well, trapping water in every joint. Galvanised screws within a kilometre of the sea, weeping rust down each fixing line by the second year.

The species is usually innocent. Bengkirai, merbau and ulin are all durable enough for this climate when they are allowed to dry, and none of them survives being kept permanently damp. So the money goes underneath: pedestals or shoes that lift the frame, cross-ventilation paths that actually connect to open air, drainage falls that send water off the deck rather than into it, and stainless fixings as standard anywhere near the coast.

Bringing a grey deck back

Silvering is cosmetic — UV breaking down lignin in the top fraction of a millimetre. Underneath, the timber is usually sound, which is why restoration so often beats replacement on value. The sequence is: strip any failed coating, refix or replace boards that have split or cupped badly, sand through two or three grits, then saturate with a penetrating oil while the timber is genuinely dry.

Timing matters more than people expect. Oiling damp timber traps moisture and the finish lifts within weeks, so we schedule restoration into dry-season windows or after a run of clear days, with moisture readings taken before the first coat goes on. After that, expect to re-oil every six to twelve months depending on exposure — a pool deck in full sun works far harder than a shaded terrace, and we will tell you which one you have.