
Why not just pressure wash?
A high-pressure jet held too close can tear up soft timber fibres and leave a furry surface. Specialists use controlled pressure with timber cleaners and brighteners to let the chemistry do most of the work.
What’s usually involved
- ✓A timber cleaner to lift dirt, mould and grey surface
- ✓An oxalic acid brightener to reduce tannin and black water stains
- ✓Rinsing and letting the deck dry fully
- ✓A maintenance coat of oil once dry
- ✓Protecting plants and nearby surfaces from run-off
Wash or sand?
If the old oil has simply weathered and the timber is sound, a wash and maintenance coat can be enough. If there’s peeling coating, deep greying or splintering, a full sand is usually the better option.
Coastal conditions to keep in mind
Salt air, strong UV and summer heat on the Illawarra coast break down deck coatings faster than inland. North- and west-facing decks and decks close to the beach usually need more frequent maintenance. Follow the oil maker’s guidance on recoat intervals and on drying time, and avoid coating in rain, dew or full midday sun.

Frequently Asked Questions
Will a wash get rid of all the grey?+
It usually brightens it a lot, but very deep greying or damaged surface fibres may need sanding. Your specialist can test a patch.
Is oxalic acid safe for my garden?+
Brighteners should be used as the product label directs. Ask your specialist how they protect plants, pets and nearby surfaces and handle run-off.
How Shellharbour Deck Care works
Shellharbour Deck Care is a lead-matching service connecting Illawarra and South Coast homeowners with independent timber deck restoration specialists. We don’t do the work ourselves. The specialist you’re matched with quotes, carries out and is responsible for the job, so ask them about insurance, the products they use and any warranty before you go ahead.