Repair large cracks in wooden flooring in Hong Kong

Large cracks have formed in my parquet floor. What's the best way of filling them in before sanding and re-sealing?

You can fill in the cracks with Colour Wood Filler from the German brand Osmo (www.osmo.de) Available in a wide range of timber shades including beech, oak, light and dark maple, cherry, white and clear. It costs HK$32 per tube from Hop Sze Timber Company, 425 Lockhart Road, Wan Chai (tel: 2833 6069).

Apply it with a plastic scraper or a cloth. Work it into the cracks with a slight circular motion, making sure the filler is packed into the gap. Work quickly and remove surplus filler before it dries. If you think your flooring will suffer from movement, you might need a silicone-based filler instead.

The wood filler called 'No More Gaps' by Australian firm Selleys is applied with a silicone gun. It also comes in a variety of colours and expands and contracts with the flooring — HK$18 per tube from Hop Sze Timber Company.

Why Does Wooden Flooring Crack in Hong Kong?

If you have been in Hong Kong for any length of time, you know the climate is brutal on timber. The fundamental problem is the humidity cycle. During the wet season (March to September), relative humidity regularly hits 90% or above. Wood absorbs that moisture and expands. Then during winter, when you are running the heating and humidity drops to 50-60%, the wood contracts. This constant expansion and contraction cycle puts enormous stress on floorboards and parquet tiles, and cracks are the inevitable result.

Parquet flooring is especially common in older Hong Kong flats — those small interlocking timber blocks laid in herringbone or basket-weave patterns that were the standard floor finish from the 1960s through to the 1990s. I work on parquet floors all the time, particularly in Mid-Levels, Happy Valley, and the older buildings on Hong Kong Island. The good news is that parquet is generally repairable. The bad news is that the cracks will come back unless you manage the humidity in your flat.

To minimise floor movement, I recommend keeping your indoor humidity between 50% and 65% year-round. Run a dehumidifier during the wet months and consider a small humidifier in winter if you use heating heavily. A basic hygrometer (HK$30-$50 from any electronics shop) lets you monitor conditions. This single step does more for your timber floors than any repair product.

Can You Fix Cracked Floorboards Without Replacing Them?

In most cases, yes — and it is well worth doing before you resort to a full replacement. Here is a breakdown of the repair options depending on the size of your cracks:

• Hairline cracks (under 1mm) — These are cosmetic and can be left alone, or filled with a colour-matched wood filler like the Osmo product mentioned above. Apply with a flexible plastic scraper, working at a slight angle to the crack. Wipe away excess immediately with a damp cloth. Cost: around HK$32 per tube.
• Medium cracks (1-3mm) — Use a two-part epoxy wood filler for a more durable repair. Mix the resin and hardener, press firmly into the crack, and sand flush once cured. Araldite or Bostik brands are available at most hardware stores for around HK$40-$60 per pack.
• Large gaps (3mm+) — For these, a flexible filler like Selleys No More Gaps is essential. Rigid fillers will simply crack again as the wood moves with the seasons. Apply with a caulking gun, smooth with a wet finger or spatula, and allow 24 hours to cure before sanding. At HK$18 per tube, it is also the most economical option.
• Very wide gaps or missing pieces — If individual parquet blocks have come loose or broken, you may need to source replacement timber strips. Hop Sze Timber on Lockhart Road in Wan Chai can usually match common species like teak, oak, or meranti. Individual replacement blocks cost around HK$5-$15 each. Glue them in with PVA wood adhesive and weight them down overnight.

After filling, the floor will need sanding and re-sealing. For a DIY approach, you can hire a floor sander from some hardware suppliers for around HK$300-$500 per day. Start with 60-grit sandpaper to level the filler, then work through 80-grit and 120-grit for a smooth finish. Seal with two to three coats of polyurethane floor varnish (HK$200-$350 per litre), allowing each coat to dry fully before applying the next.

If your floor is generally in decent shape but looking tired, a full sand and re-seal without any major crack repair typically costs around HK$15-$25 per square foot when done professionally. It transforms the look of a flat and is one of the best value-for-money improvements you can make before selling or re-letting a property.

While you are working on your floors, it is also a good time to check your timber furniture for similar humidity damage. Dining tables and wooden shelving suffer from the same expansion and contraction problems. For more information on carpet alternatives and other flooring repairs, see our guide on stair carpet repairs. You can find all our interior guides on the interiors index page.

When Should You Call a Professional?

Floor repairs are satisfying DIY work, but there are times when professional help is the smarter choice:

• If more than about 20% of the floor has significant cracking or loose blocks, a professional floor restoration specialist will be faster and achieve a better finish
• If the subfloor underneath is damaged by damp or termites — termites are a real problem in Hong Kong, particularly in older buildings and village houses in the New Territories — you need specialist treatment before any cosmetic repair
• If you want a perfectly level, showroom-quality finish for selling or letting the property, professional drum sanding equipment gives results that hand sanding simply cannot match
• If the parquet is an exotic or expensive timber and you are not confident about colour-matching fillers — getting the tone wrong is very visible on a large floor area

Last updated: March 2026