12 October 2026 · Timber Deck Sanding

Why Tamarin Decks Turn Grey — and When Sanding Brings Timber Back to Life

The silvery driftwood look suits a beach. It rarely suits a villa deck. Yet across Tamarin, Flic en Flac and the estates above the bay, hardwood decks silver over faster than most owners expect, sometimes within a single wet season of missed oiling. The good news: grey timber is not dead timber. In most cases the rich original colour is sitting just a millimetre below the surface, and sanding brings it back.

Understanding why decks grey in the first place tells you whether your deck needs a sand or just a proper clean and re-oil. Here is how it works on the west coast, and how to make the right call.

Why west coast timber silvers so fast

Greying is photochemical. Ultraviolet light breaks down lignin, the natural polymer that binds wood fibres together and gives timber its colour. Those broken-down fibres sit at the surface as soft, grey, dead cells that slowly wash away with rain, exposing fresh timber underneath, which then greys in turn. Left alone, a deck erodes this way season after season.

Tamarin's coastal climate accelerates the process threefold. Strong west-coast sun delivers intense UV exposure. Salt air dries the surface and opens the grain. Humidity swings between wet and dry seasons cycle the boards, creating small surface checks that let UV penetrate deeper. A deck in the hills near Tamarina Golf Estate may take two years to silver noticeably; the same deck on a Flic en Flac beachfront can silver in six months without protection.

Grey is cosmetic — splits are not

Before reaching for a sander, check whether the damage goes deeper than colour. Grey surface fibres are an aesthetic problem and completely recoverable. But long neglect, especially with salt exposure, can also bring cupping, surface checking and soft spots around fixings, which are structural issues. Run the flat of your hand across the boards: a grey deck that still feels tight, firm and even is a sanding candidate. A deck that is splintering, cupping or cracking needs a proper condition assessment first, because sanding thin, checked boards can do more harm than good.

The water-drop test: clean or sand?

There is a simple way to tell whether your grey deck needs a clean or a full sand. Splash a small puddle of water on a greyed board and watch what happens. If the timber absorbs the water quickly and evenly, darkening as it wicks in, the pores are still open and a deep clean with a timber cleaner or oxalic wash, followed by oil, can restore most of the colour without sanding.

If the water beads on the surface and sits there, the pores are clogged with dead grey fibres, salt residue and oxidised cells. No cleaner or oil will penetrate that layer properly. This deck needs to be sanded back to sound timber before it will hold a finish, and oiling over it will only create a blotchy, peeling mess within weeks.

What sanding back actually involves

Sanding removes the grey weathered layer — usually less than a millimetre — to reveal fresh timber and reopen the grain so oil can soak in and bond. The essentials:

Grit matters more than speed. Start around 40 to 60 grit, then finish at 80. Going straight to fine grit burns the surface, polishes dead fibres instead of removing them, and leaves grey patches behind. If you are choosing equipment, our grit and machine guide for Tamarin decks covers the options.

Sand the whole board, not the grey patches. Spot-sanding a few grey areas creates visible dips and colour banding. Always blend the full board, and remember that full preparation steps are in our how to sand a deck guide written for west coast conditions.

Re-oil within a few days at most. Freshly sanded timber is vulnerable and will start to silver again quickly in Mauritian sun — especially in the wet season when UV and moisture team up. Follow sanding within days with a penetrating oil. Our guide on choosing oils for the Mauritius climate will help you pick the right product.

How often should a coastal deck be sanded?

Sanding is a reset, not a routine. A well-maintained deck that is kept oiled should only need sanding every 3 to 4 years, or when colour and texture have visibly deteriorated after extended time between oilings. Heavy-traffic areas on beachfront properties may need it more often, especially on resort decks where guest traffic and salt spray have ground the surface down together.

Two smarter cards to keep up your sleeve: the salt-spray washing routine that slows silvering on exposed decks, and the Tamarin oiling schedule that keeps you ahead of the UV cycle so sanding stays a once-in-a-few-years job, not a yearly one.

When to call it a grey deck you should not sand

If the grey timber is also soft underfoot, the boards are cracked, the fasteners are raised, or sections flex visibly when walked on, the problem isn't at the surface and sanding will simply expose it. In those cases the deck needs repair or partial board replacement first, and only a light finishing sand afterwards. This is where a professional inspection pays off: it tells you which boards are sound enough to sand back and which need swapping before you invest in a full restoration.