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Gap Filling and Floor Restoration


gap fillingGaps, Draughts and Wooden Floors

Wood is a natural material. It possesses the ability to absorb and release moisture from and into the air (Also known as hygroscopy). As a result, wood can shrink or expand depending the conditions. And those conditions change often as the seasons roll.

Wood swells during the summer and, of course, contracts when winter approaches. This property leads to the appearance of gaps. Gaps are problematic not simply because they make the floor appear unattractive, but because they can also be a reason for draughts which will increase your heating bills in the cold winter months. Regardless whether you want a better-looking floor or have the desire to save money from heating, gap-filling is an excellent way to have both.

What is Causing the Gaps and How to Prevent Their Appearance?

There can be many reasons. – from using lesser quality floorboards to bad installation or lack of proper acclimatisation before fitting. If the hardwood is allowed at least 10 days of acclimatisation prior to the installing, you are much less likely to experience any issues.

Gaps appear during the winter because humidity is low and all the moisture contained in the wooden floor is released into the air. If the temperature in the room is more consistent, though, the gaps simply will not show up. This can be done with the help of a house humidifier which will reduce the moisture levels. In the summer, an air condition can keep the air cool.

However, not all gaps have something to do with moisture and temperature. As we have already said, sometimes the boards are simply laid badly. At this point, you have two options – sand the floor and fill the gaps or reinstall it completely. If you are afraid you will experience problems, it is good to know that engineered wood is less susceptible to moisture and not as likely to allow the appearance of gaps.

How to Fill Gaps in Wood Flooring?

There are several methods to fill the gaps between the planks. The two most popular ones involve the use of a filler resin or wood slivers. The first method (resin) is better for small gaps simply because it is more efficient. For bigger gaps, however, you better use the slivers. None of the methods is truly superior, they each have their application.

Filling with a mix of resin and sawdust is the optimal choice for gaps between planks of up to 6mm. This is one of the cheapest and most frequently used methods. Another one of its advantages is the fact that the sawdust allows the resin to acquire the natural colour of the floor and blend in pretty convincingly. However, in order to get sawdust that perfectly matches the natural colour of your floor, you better sand the floor first. Sanding and gap-filling are two services which work very well in conjunction!

As for the resin application, it is rather easy. The resin and the dust are mixed in a bucket and applied with a filling knife or spatula. Any excess material is then sanded before the finish is applied. The only trick here is to mix small amounts of resin and work fast because the resin dries easily.

Gap filling with wood strips is best used for gaps between the planks wider than 6mm. The strips are cut from reclaimed pine timber, which would match your wood floor as close as possible in colour. The wood strips are glued and hammered in the gaps. Generally, this method is not used that often because the extra wooden material is expensive and the whole takes a bit longer to complete.  In addition, the wood slivers may sometimes split down the middle because they do not allow the floor to move a lot.

Gap filling with Bona gap master filler is applicable to tiny gaps between the planks, minor repairs, cracks and filling around beadings and skirting boards. Bona gap master filler is manufactured in different colours, in order to match the one on your wood floor. Gap filling with Bona gap master filler is expensive but its benefits are undeniable. The main advantage of the filler is its flexibility with 7% expansion rate and odour-free.

Also, it’s good to keep in mind there are alternative but less popular methods for filling like PVE glue and sawdust (already outdated) or simple papier-mâché for older, more ‘vintage’ appearance. For more information on gap-filling, you can always turn to us.




FlooringFirst! Services
158 Coles Green Road
London, NW2 7HW
T: 0800 0434359