How Do I Fill the Gaps in my Hardwood Floor ?

Hello and Welcome to another Woodfloor-Renovations Blog post.


This subject really is the one I get most correspondence about, its a fairly simple process really but if its done badly or you don't know what you are doing or what products you should use then things can go very wrong very quickly. 


This Blog is about Gap Filling your wood floor, it doesn't matter if you have a beautiful hardwood Oak Parquet Block floor or old softwood Pine Floorboards, the principles are the same as is the method for getting the job done. The Gap Filling part of the Sanding & Sealing process is carried out shortly before applying the first coat of seal to the floor so it really does need to be done correctly otherwise your floor could easily look a mess.


Two main components are needed for Gap Filling are some nice clean fine sanding dust from the floor/species you have been sanding, and the Filler itself.

 There are two distinct product types in the Filler market, Solvent Based Fillers v's Water-based Fillers, both have different properties and behave differently, for example the solvent based fillers have a quite pungent smell when used, and the Water-based fillers don't, with solvent based fillers you have a quite short working time whereas the water-based fillers have a  long open time.


I can tell you are leaning towards the water-based products already :-) but before you make up your mind read on.

 From a Professional standpoint I personally almost always use solvent based fillers, this is because a solvent based filler dries really quickly [10-15 mins] and most of the filling I do is for relatively small area's in respect of the overall job. I need the filler to go off quickly to be able to move onto the next phase of the operation which would be to properly Sand off any residues and to finish the preparation on the newly sanded floor.

The two above pictures are of the exact same area from a recently completed job, where the pictures clearly show the dramatic difference that applying filler can make, in the top pictures your eye's are drawn to the 'black gaps' that can be seen pretty much everywhere in that picture. In the lower picture you can clearly see the difference that the gap filling has made - believe me that particular floor took some gap filling :-(( 

Click on the link and you will be taken to the complete Gallery of that project - the before and after pictures are quite startling   Conwy Valley Pitch Pine Job

The main component of gap filling is the dust, make sure it's nice and clean and at least 80 grit and finer, meaning 120 grit dust is better again, mix the filler into the dust, to the consistency of a thickish custard, don't worry if you pour on too much filler and it goes very runny, simply add more dust and mix well.

When properly mixed you basically scrape the mixture into the gaps, somewhat similar to grouting tiles. I would advise using as wide a scraper as possible as gap filling can be a very time consuming and tedious job if all you have to use is a 4" wallpaper scraper.

As soon as you apply the filler mixture to the area you are filling, make sure you scrape off as much of the residues as possible, as when the filler dries, it dries hard and can be difficult to remove if thick residues have been left on the floor to dry.

Remember - Solvent based fillers have an approximate 10-15 minute working time, while the water based fillers have a much longer open time, and can be as much as an hour or more before it is properly dry depending on how wide the gaps are...the wider the gaps the longer the drying time and that refers to both filler types.

Hope this article helps - Good Luck with your project.

From Behind The Machine....Our first post

Hello and welcome to the Woodfloor-Renovations first ever blog post...

Over the coming months I'll be commenting on many Floor Sanding related topics, such as Gap Filling, or whether to use Lacquer or Oil as your floor seal of choice, I'll also be giving you an insight as to my perspective on the trials and tribulations of a professional Floor Sander. 


I'll be trying to answer questions sent in via email on Wood Floor Sanding topics, so if you have any issue's with your project or are just wondering 'How do I' do this or that....email me or ask through the Blog and I'll try and answer the question.

The question I'm most asked is 'should I use Lacquer or Oil on my wooden floor ?'

Its a reasonable question, unfortunately there isn't a straightforward answer....it's mainly down to personal preferences but there are many things to bear in mind before making the decision on which Seal to use on your project.



An Oiled finish can give a greater depth of colour to the floor, while a lacquered finish may leave the floor slightly more pale in appearance, but this can be entirely dependant on wood species... Normally 2 coats of Flooring Oil are applied to a properly prepared wood floor, while most professional Floor Sanding Companies will apply 3 coats of Lacquer as standard. Under normal traffic conditions, an oiled finish should last between 12-18 months before needing more coats of Oil to be applied, whereas Lacquer should last between 3-5 years before needing attention.

These timings are approximate and depend on a number of variables, such as :-the Cleaning regime employed by the home-owner, the volume of traffic in the home, and the type of shoes that go over the floor......


Both Lacquers and Oils are available in different sheen levels, with Lacquers the sheen levels are usually:- Extra Matt, Matt, Satin, Semi Gloss and Gloss, while Oiled Finishes usually come in:- Matt & Satin finishes.


It is highly recommended to always use the proper wood floor cleaning products from the manufacturer of the Lacquer or Oil you have applied to your floor....Why?? i hear you ask.

The answer is quite simple.....the Lacquer/Oil manufacturers wood floor cleaning products are designed to work specifically with the Seal you have just applied to your wooden floor, their usually easy to follow instructions make cleaning your beautiful newly Sanded & Finished Floor quick and very easy, these products are normally cheap and readily available.   


Do a Google search for:-wood floor cleaning kits / you will get many results and varying prices, one of the best cleaning kits on the market is from Bona, and is cunningly named The Bona Wood Floor Cleaning Kit....the kit comes complete with a wide mop, extension pole and the cleaning solution all in the box, expect to pay between £20 - £25 for the kit, now i know this is quite alot of money but bear in mind that the material head of the mop is machine washable and the 1 litre of cleaning solution will last many months before a refill is needed.


Thanks for Reading.....