How to Maintain and Clean Different Types of Decking: Expert Tips for Long-Lasting Beauty

A well-cared-for deck pays you back with years of barbecues, kids’ parties and quiet morning coffees. Ignore upkeep, and the same structure can become a slippery, splinter-ridden liability. The trick is matching your maintenance routine to your decking material and New Zealand’s coastal, sun-soaked climate. Use the guide below to keep timber, composite, PVC, aluminium and bamboo boards looking showroom-fresh for decades.
Quick Table of Contents
- Know your decking material
- Care routines for each surface
- Eco-friendly cleaning fixes
- Seasonal protection every Kiwi needs
- Common mistakes to avoid
- Frequently asked questions
- Ready for professional help?
1. Know Your Decking Material
Material | Key Strengths | Watch-outs |
Treated pine, cedar, hardwood | Warm natural look, easy to sand and refinish | UV fade, rot, tannin bleed |
Composite | Fade and stain resistance, splinter-free | Needs correct gap spacing, can show grease marks |
PVC / vinyl | Zero water absorption, lightweight | Surface scratches show, darker colours heat up |
Aluminium | Fire-safe, insect-proof, non-warp | Can dent, powder-coat sensitive to strong chemicals |
Bamboo | Fast-growing renewable resource | Must stay sealed, prone to surface mould in shade |
Knowing the quirks lets you pick cleaners and sealants that add life instead of stripping it.
2. Care Routines for Each Surface
Wood Decking
Weekly sweep and rinse
Remove leaves, dirt and grass to cut down on moisture traps. A garden hose and soft broom are all you need.
Quarterly wash
Mix warm water and a squirt of pH-neutral dish soap. Scrub with a medium-stiff nylon brush, working with the grain. Rinse thoroughly. High-pressure washers can shred fibres, so keep nozzle pressure under 1 500 psi and fan the jet.
Annual seal, stain or oil
Coat all sides of replacement boards before installation to slow cracking and cupping. Choose a penetrating oil with mould inhibitor if your deck sits in damp shade. Apply on a dry, wind-free day above 10 °C.
Spot rot repairs
Probe suspect boards with a screwdriver. Soft spots mean decay: cut out affected areas and treat framing with timber preservative before installing new H3.2 pine or hardwood.
Composite Decking
Routine clean
Sweep weekly, then hose off grime. For a deeper wash, use mild dish soap or a purpose-made composite cleaner and a soft brush. Avoid chlorine bleach; it can alter pigment and corrode hidden clips.
Six-monthly deep clean
- Remove furniture.
- Rinse boards to cool them and loosen dirt.
- Apply cleaner per label instructions.
- Agitate lightly with nylon bristles, paying attention to board gaps.
- Rinse until runoff is soap-free.
Oil or grease spills? Blot with paper towels, then apply a degreaser approved by your board brand and rinse again.
PVC and Vinyl Decking
Weekly wipe-down
A bucket of warm water and a dash of dish soap is enough. Rinse well to stop film build-up.
Stain and scratch fix
Most food and leaf stains lift with non-abrasive household cleaners. For fine scratches, feather the edges with 400-grit wet-and-dry sandpaper, rubbing parallel to the grain, then clean off dust.
Mould patrol
Mix one cup of white vinegar in four litres of water, scrub affected patches and rinse. Vinegar kills spores without damaging plasticisers.
Aluminium Decking
Powder-coated aluminium looks after itself, but dust dulls the sheen.
- Hose off quarterly, loosening dirt with a soft sponge.
- Use a pH-neutral, non-abrasive car-wash soap for stubborn grime.
- Skip acidic or alkaline cleaners that can etch the coating’s gloss.
Bamboo Decking
Bamboo’s dense fibres need regular cleaning to avoid mould.
- Soak boards with water.
- Scrub with a specialist bamboo cleaner such as WOCA Decking Cleaner or a mild detergent.
- Rinse dirty residue off and let boards dry fully.
- Re-oil yearly with a UV-stabilised exterior oil.
3. Eco-Friendly Cleaning Fixes
- Vinegar solution: Equal parts white vinegar and warm water lifts algae on both timber and composite decks.
- Baking soda paste: Scatter baking soda on a wet stain, brush lightly, then rinse. It neutralises odours and lightens tannin rings.
- Oxygen bleach (sodium percarbonate): Safer on plants than chlorine bleach and breaks down to soda ash and oxygen. Use on grey, mildew-stained wood.
Always test a hidden patch before tackling the whole deck.
4. Seasonal Protection Every Kiwi Needs
Season | Checklist | Reason |
Spring | Deep clean, inspect fixings, re-oil wooden boards | Prepares surface for heavy summer traffic |
Summer | Apply UV-resistant oil or sealant and move potted plants weekly | The sun is strongest December-February |
Autumn | Clear leaf litter; ensure gutters and downpipes drain away from the deck. | Leaves trap moisture and tannins |
Winter | Remove furniture, store cushions inside, use plastic shovel for snow in alpine regions | Prevents surface scratches and moisture saturation |
Don’t forget the hidden underside. Annual sweeping and a quick rinse under the deck stops mould and deter insects.
5. Common Mistakes to Avoid When Deck Cleaning

- Too much pressure: Water jets over 1,500 psi raise grain on timber and leave “zebra stripes” on composite.
- Skipping the gaps: Leaves lodged between boards create perfect mould nurseries. Clean between slats with a plastic scraper.
- Wrong chemicals: Bleach corrodes fasteners and fades colour. Stick to pH-neutral cleaners.
- Ignoring the fixings: Loose screws invite board movement and squeaks. Tighten annually and replace rusty steel within 2 km of surf with stainless.
- No ventilation: Stacked firewood or planters pressed against rails trap moisture and lead to decay.
Frequently Asked Questions: Deck Maintenance
How often should I clean a wooden deck?
A light clean monthly and deep clean plus reseal once a year is a good rule in most of Aotearoa.
What is the safest way to remove mould from composite boards?
Use a manufacturer-approved cleaner or a vinegar-water mix followed by gentle brushing and a thorough rinse.
Can I sand PVC decking?
Only for minor scratches and with fine wet-and-dry paper. Test a small area first.
Do aluminium decks need sealing?
No. The factory powder coat is its own seal. Just wash with soapy water.
My bamboo deck has gone grey. What now?
Clean, let it dry, then apply a tinted exterior bamboo oil to restore colour.
Is it worth cleaning underneath the deck?
Yes. Debris and mould on the underside accelerate rot and can void warranties.
Ready for Professional Deck Cleaning?
Regular TLC extends a deck’s life, yet some jobs demand specialist gear and know-how. From rot repairs to full resurfacing, our vetted deck specialists make your deck look new again.
Keep these tips handy and roll out a regular schedule, and your deck will stay the star of your backyard every season.