Hours & Map

Yes, you can refinish a hardwood floor.

Let us show you how. Minnesota do-it-yourself homeowners are our specialty. We ♥ DIY-ers.    Store hours   Map to store

This is a very bossy article about using woodfiller on hardwood floors:

Because filler is not a cure-all; it is a necessary evil

filler looks bad in big scratches for webI know you’ve seen those old-timey ads for tonics that claimed to cure dandruff, bad breath, warts, bunions, indigestion, shyness and malaise, all with one dose. And you've laughed at the idea that anyone ever beleived those outlandish claims. You would never believe unrealistic promises. But even though we’ve all been trained to doubt products that sound too good to be true, most people continue to believe that woodfiller will fix just about anything that ails a hardwood floor.  But in the world of hardwood flooring, woodfiller is designed to camouflage small holes and chips in the floor, and that’s it. It can't make large scratches disappear. It doesn't hide large holes. No matter what the packaging promises, filler does not take the place of wood. Ever. Look at the example board we made on the right. Long diagonal scratches look worse after filling. Large round areas of fill look like round areas of Play-Do. 

So here, in no particular order, are all our favorite thoughts on the many weaknesses (and occasional strengths) of woodfiller on hardwood floors.



Woodfiller does not permanently fill gaps

gaps-filled-with-dirtregular-hardwood-floorNotice the important word here: permanently.  Woodfiller can temporarily fill anything, even the annoying gaps that run parallel to the long edges of your floor boards.  But the size of those gaps changes all year long and the woodfiller in those gaps isn’t elastic enough to swell and shrink with the seasons and so will just get pummeled and eventually break up and look like kitty litter.  Kitty litter trapped forever in your flooring gaps. Open, honest gaps are far more attractive than dirty, poorly filled gaps.


My Floor Guy says I should always trowel-fill floors before sanding. What does that mean?

gappingfloor.jpbTrowel-filling is exactly what it sounds like: spreading large quantities of filler over theTrowel fill is a mistake 2 entire area of a floor, allowing it to dry hard, then sanding off everything that doesn’t fill a void. In some cases (and in the hands of a professional) this procedure can have some benefits: on very new floors in climates where the boards don’t swell and shrink very much through the seasons, trowel-filling does help keep the finish contiguous. But in older, already gappy floors in climates with season extremes (yes, like Minnesota) the benefits of trowel-filling are short-lived. Within a year, the movement of the floor will break up the filler, leaving you with a finish which is no longer contiguous, plus a lot of loose fill between the boards. In the photo at right, the filler must have look great when it was freshly done - it even took the color of the stain perfectly. But just a few years later, it looks like someone tried to fill the gaps with Nutella.



Woodfiller is not a substitute for board replacement

shame fillergouges wicked badWood has grain; woodfiller does not, so large areas of woodfiller look nothing like the wood that surrounds it.  Even when it does take on the color of the stain or finish you use, it will still look like a big, undifferentiated blob on your floor.  When you use filler on nail holes and chipped board corners, it camouflages well in the grain pattern of the wood.  But large areas will stick out like a black eye. This is especially important if you have hollows or depressions in your floor – these are better simply sanded clean and left alone.  Hand-coat those spots if you must to keep the finish from getting too thick, but do not try to “level” a hardwood floor with filler.

The bigger the area you fill with woodfiller, the more it will shrink. Larger voids also require that you apply the filler in stages (because it will shrink after each application). And the more applications, the longer it will take to dry before you sand it.  If you are using so much filler that it takes more than an hour to dry hard enough to sand, you are probably using it inappropriately. 


I get it - you don't want me to put filler in those cracks.  But my finish will run into those gaps and fill them nice and flush, right?

Again, no.  Floor finish is designed to be quite runny so it will flow and seek its own level on your floor, and it will run right through your cracks and down to your subfloor. Glues and epoxies will do the same thing because the gaps in your floor have no bottom. 

My hardware store has these cute little pots of Color Putty in dozens of colors - why can't I just fill all my cracks with that?

This is the perfect juncture to explain that there are two different kinds of products you can use on a floor. Up until this point we've been talking about the kind that starts out soft and pliable so you can work it into all the holes, but it dries hard and must be sanded flush to the level of the floor, and to remove all the extra filler that went into the wood grain around the hole. This kind of filler comes in a narrow range of colors and you choose the one that best matches the background color of your RAW wood, and it should then take on color (stain or finish) as your wood does.  Color Putty and other soft putties are designed for wood that is already finished. These fillers are already pre-tinted in a much wider variety of colors than hardening fill. Because you simply press them into the hole and you're done, you need to have a precise color match to the finished tone of your wood. The problem with Color Putty is that it NEVER HARDENS! It is designed this way - this allows you to putty it into the void in your floor, and then wipe away the excess without having to sand your nice finished floor. But Color Putty stays soft and, if applied in frequently walked-on areas, will eventually work itself out again. You can easily reapply it, but it is something you have to keep up with.

Igap shrinkage cork’ve heard about filling my wood gaps with rope – why can’t I do that? 

Cork is better than fillerIt’s true that rope won’t crack and fall out like filler, but it won’t look like wood either.  At best, it will reduce the amount of sand and debris that can collect in your floor cracks, but it won’t do much else.  You can use rope as a way to fill up a big crack and then just top up with filler (so you don’t have to use as much filler), but the filler itself will still crack and fall out over time; there will just be less of it. If your gap is truly wide enough to even consider filling it with rope AND the gaps don’t close up in summer, use cork instead.  It’s sold in strips of different thicknesses, it’s easy to cut and you can use a cheap dental tool (Harbor Freight has good ones) to push the strip of cork into the gap.  You can even use a little paintbrush to apply finish to the cork when you’re done.  If you’re using cork on gaps, do it after you sand and finish the surrounding floor. (threshold gap photo from customer).  Cork is also a great material to use where leaving an expansion gap might be unsightly, for example when wood is installed flush against a fixed obstacle like a fireplace or a sliding glass door


Then what should you do with wide gaps, big holes and gouges?

First, try to fill them with actual WOOD; it doesn’t sink and it shrinks and swells with the wood surrounding it. If the problem area is too small to warrant removal of the board, but too big for fill, drill it out to a regular circle and fill it with a face-grain wood plug (or even several in a row) in the same species as your floor. These blend into the floor beautifully, and are a fraction of the work of replacing a whole board. Slices from a dowel will work in a pinch, but they will absorb stain more deeply than the wood of your floorboards and will appear as a darker circle; face-grain plugs match the grain direction of the actual flooring and will blend and take finish much more seamlessly. We sell the most darling, tapered face-grain plugs in maple, red oak, walnut and cherry in various sizes.  For wide gaps, use a Dutchman – a tapered shim of wood that is pounded in to the gap, nipped off and sanded flush.

When you do choose to use filler, there are some products that we adore and use on the Timbermate for thumbnailcontracting side of our business and will be delighted to sell to you.

We adore this pre-mixed filler because it shrinks less than any other filler we have tried, which makes it a better choice if you insist on filling larger areas.  It also takes the color of stain, Rubio and polyurethane better than other fillers. And even if it dries out, it easily reconstitutes with water. We carry it in Red Oak, White Oak, Maple, and Ebony. Also can be tinted with universal colorants if you need to make a custom color.

$15 for 8oz Click here to buy some!



Wood Flour Cement 1Glitza Wood Flour Cement mixed with 80 grit wood dust that matches the wood of your floor. Don't use wood glue and dust to make filler - it always dries more yellow that you think - unsightly!
The wood flour cement has two main strengths: the epoxy itself lasts forever, and you can mix up only as much as you need for each job, so there is no waste. Second, you can mix up a different color for the spot you’re filling, just by mixing in a different color of dust.  Because sometimes, a light spot in an oak board will actually look better with maple-toned fill.

Unfortunately, this is only available by the gallon and, because of its toxic nature, cannot be shipped

$66 per gallon  Available in-store only



Once you've decided to use woodfiller, use it responsibly! These tips will help:

  • Fill after you've sanded through 36 grit.  Don't fill at the very beginning - you won't see all the places that need fill. But don't wait until the end of the job either because the filler that sticks in the wood grain around the void you've filled needs to be completely removed or it will look like a liitle halo around each filled spot, once the finish is applied.
  • filler badMatch the filler to the color of the spot you are filling, not just to the specie of the whole floor. Maple floors have dark spots and oak floors have light sections, and all floors have at least one dark knot. Use your eyeballs, not the name of the filler to guide you.  If you are filling knots, use an ebony fill, or use universal tints to darken a small amount of your red oak fill. But don't assume that one color will fit all your filling needs.
  • Give your filler time to dry before you sand it flush. We recommend applying filler right before stopping for lunch or before you leave for the day. As long as you aren't trying to fill the Grand Canyon, it will be dry by the time you're ready to start sanding again.

Pete’s is your Minnesota hardwood floor refinishing expert!

Visit our flooring supply and rental store.

186 Fairview Ave North, St. Paul, MN 55104

Store Hours:

Monday: 9-4
Tuesday: 9-4
Wednesday: 9-4
Thursday: 9-4
Friday: 9-4
Saturday: 9-3
Sunday: Closed
Pete's does not require masks unless you are NOT vaccinated.

Are you local? Call the store!


Can't get to the store?

For "out-of-staters," we sell some of our favorite products online. 
Shop now

Hardwood floor advice so you can refinish your own floors.

Look, we’re not promising to turn you into a flooring professional with one lesson. But we guarantee you will do a better job than that contractor you're thinking about hiring off of Craig's list. More

Pete’s gives free lessons? How does that work?

Here at Pete’s Hardwood Floors, we rent all kinds of floor installation and refinishing machines, but you can learn to run them on an actual floor. Take a test drive with our hardwood rental equipment. More

YouTube logo

Watch videos on Pete's YouTube.

Check out our YouTube channel. Especially the polyurethane application video - it's the best explanation for coating you've ever seen.

Think twice before using stain.

For most do-it-yourselfers, a natural finish will produce the best results. Applying pigment evenly to a large expanse of wood is more challenging than you think. More

Rent the right hardwood rental equipment

ez 8 drum sanderFour out of five floors NEED a drum sander.

We know drum sanders have a bad name, but we can show you how to tame them and use their power for good. And save you time and money into the bargain. Who said floor sander rental can't be fun? More

U-SandWhen drum sanders aren't the answer, try the U-Sand.

The U-Sand won't work for every floor, but if you can't run an edger, the U-Sand might save you. More

Use a buffer to maintain your polyurethane?

No, not to polish it, but to prepare it for a fresh topcoat. If you regularly recoat your floors, you will never have to rent a sander again. Doesn't that sound fabulous? More

bostitch MIIIFS prettyFloor stapler v. cleat nailer: is one better than the other?

It depends on what kind of wood and how thick it is. Cleat nailers are less likely to split the tongues of dense, brittle woods like bamboo and brazilian walnut. More

Did you know there are special sanders, just for radiators?

Sanding under those cast iron radiators is way, way easier than removing them. More

What do I do with all my belongings? Can you rent me a storage unit?

Dart storage logoAs a matter of fact, we can! We have special, negotiated rates through Dart, a local portable storage company. Call 651-683-1219 and tell them Pete's sent you.

Renting sanders twice (and moving your furniture twice as well) is always more expensive than doing the job in one stage, even when you include the cost of storage. Call them now!

Read Kadee’s Top 5 most
popular articles

Afraid of coating? Us too.

Once your floor is sanded, you face a new challenge: how do I choose a finish and how do I apply it without leaving streaks and bubbles and problems?  We are familiar with this anxiety and we have a solution... more

Let us talk you out of staining your floor...

What? Floors don't have to be stained? Yes, you heard right. Wood floors should all be protected with something, but stain is not protection; stain is a way to color your floor before you add protection. It is optional and we want to convince you not to do it. Here's why:

What do I do about the gaps between boards?

Everybody thinks that every single gap and void on a hardwood floor must be packed with woodfiller. Woodfiller has its uses, but that is not one of them. Filling the cracks between your boards is a tricky business - read more...

Cat pee and dog toenails

Do you need an indestructible surface that your pets can pee on all day while you're at work? One where you can throw the ball indoors and let your puppies chase after it all day long? Then you don't want a wood floor. Wood floor finishes have gotten really tough over the past twenty years, but customer expectations have gotten even tougher. Learn how to have realistic expectations from your floor and the finish you've applied to protect it in this article.

Think through the sanding process...BEFORE you rent a sander

Look, we have a whole business built on the premise that homeowners can sand and refinish hardwood floors, but only if they know the full scope of their project. Sometimes it is wiser to hire someone to refinish your floors for you. Did you know that some floors will take twice as long to sand to bare because they are so hard? Have you heard about old finishes that gum up sandpaper? And what if your floor needs a few boards repaired before you can sand - that'll only take a few minutes, right? Um, nope.