How do a repair sun damaged wood in Hong Kong

How do a repair sun damaged wood?

The bubbling and cracking are caused by the sun's ultraviolet rays drying out the wood. First, use a good paint stripper — water-based ones are less harsh and easy to clean up (HK$65 per litre) — and strip the paint off until only the wood is visible. This will prevent the wood drying and cracking further.

You could choose an exterior or marine varnish Australian Bondex costs HK$150 per litre, it will soak into the timber and provide protection from harmful rays. If you want to paint the door make sure you use high quality gloss finish made for exterior timber. Apply in thin coats rather than 1 single thick coating.

All materials are available at Yuen Fat Ho, Hollywood Road, Central, tel: 2546 8020, or from most Wan Chai paint shops.

Why Does Outdoor Wood Deteriorate So Fast in Hong Kong?

If you have moved to Hong Kong from Europe, North America, or Australia, you have probably been shocked at how quickly outdoor wood falls apart here. Back in the UK, a painted wooden door might last ten years before needing attention. In Hong Kong, you are lucky to get three years. There are good reasons for this.

Hong Kong hits outdoor timber with a brutal double-whammy that few other climates can match:

• Extreme UV exposure -- Hong Kong sits at roughly 22 degrees north latitude, meaning the sun is intense for most of the year. UV rays break down the lignin in wood -- that is the natural glue that holds the fibres together. Once the lignin degrades, the surface fibres lift, crack, and turn grey. South-facing and west-facing surfaces cop the worst of it.
• Relentless humidity -- Average humidity in Hong Kong runs between 75-90% for much of the year, spiking even higher during the wet season. Wood constantly absorbs and releases moisture, causing it to expand and contract. This cyclical movement cracks paint and varnish, and the exposed wood underneath then absorbs even more moisture -- a vicious cycle.
• Salt air -- If you are anywhere near the coast, airborne salt accelerates the deterioration further. Salt is hygroscopic, meaning it draws moisture into the wood and holds it there.
• Acid rain -- Hong Kong's air pollution means rain is mildly acidic, which attacks both the wood and any protective coatings.
• Typhoon damage -- Driving rain at 100km/h or more forces water deep into every crack and joint. After a typhoon, untreated wood can be waterlogged for days.

The combination of these factors means that maintenance schedules for outdoor wood in Hong Kong need to be roughly twice as frequent as in temperate climates. If you have timber decking in your garden, the same principles apply -- regular treatment is not optional here, it is essential.

What Products Restore Sun-Damaged Wood?

The good news is that sun-damaged wood can almost always be restored, provided the structural integrity is still sound. Here is my recommended step-by-step process, refined over 28 years of dealing with Hong Kong's climate:

• Step 1: Strip the old finish. Use a water-based paint stripper (around HK$65-80 per litre from Yuen Fat Ho). Apply generously, wait 15-20 minutes, and scrape off with a broad putty knife. Water-based strippers are less harsh on the wood and easier to clean up than solvent-based alternatives.
• Step 2: Sand the bare wood. Start with 80-grit sandpaper to remove the damaged surface layer, then work up to 120-grit for a smooth finish. Always sand with the grain, never across it. For large flat surfaces like outdoor tables, an orbital sander (around HK$400-600 from hardware shops) will save your arms.
• Step 3: Apply a quality exterior finish. This is where the right product makes all the difference. My top recommendations for Hong Kong conditions are:

• Sikkens Cetol HLS Plus -- My go-to for exterior wood in Hong Kong. It is a high-build, UV-resistant woodstain that penetrates deep into the grain rather than sitting on the surface like paint. This means it does not peel or blister. Around HK$280-350 per litre. Apply two coats with a brush, allowing 16 hours between coats.
• Australian Bondex marine varnish -- Excellent for hardwoods and any wood exposed to extreme weather. At HK$150 per litre, it is good value. Best for doors, window frames, and furniture that sees direct sun and rain.
• Osmo UV Protection Oil -- Ideal for teak, cedar, and other oily hardwoods that do not take varnish well. HK$240 for 500ml from Hop Sze Timber in Wan Chai.

Annual maintenance schedule for Hong Kong: I recommend a full inspection and touch-up every October, after the worst of the summer heat and humidity has passed but before the cooler, drier winter months. This gives the finish the best conditions to cure properly. Lightly sand any areas where the finish has worn thin and apply a fresh coat. If you keep to this schedule, a good quality product like Sikkens will last two to three years before needing a full strip-back and recoat.

If you have a garden gazebo, the same maintenance routine applies to all the exposed timber. Pay particular attention to horizontal surfaces where water pools -- these deteriorate fastest.

When Should You Call a Professional?

If the wood is only surface-damaged -- grey, faded, or the finish is peeling -- this is a straightforward DIY job with the products mentioned above. However, call a professional if:

• The wood is soft or spongy when you press a screwdriver into it -- this indicates rot that may need sections replaced
• There are deep cracks (checks) more than 3-4mm wide -- these may need filling with an exterior wood filler before refinishing
• The item is structural, such as a balcony railing or support post -- any repair needs to maintain its load-bearing capacity
• You are dealing with a large area such as a full deck or gazebo -- the preparation and finishing work can take several days and benefits from experience

I carry all the products mentioned in this article and can assess whether your wood needs a simple refinish or a more involved repair. A typical refinishing job on a standard external door costs around HK$800-1,500 for labour and materials.

Last updated: March 2026