To refinish a wood floor is a big undertaking, but is by no means beyond you if you are patient, and are willing to follow the correct steps in order.
In this article, we will look at how to refinish most wood floors, including hardwood, doing up the entire floor surface from initial sanding right through to your choice of stain.
Is Your Floor Suitable for Refinishing?
Not all floors can be refinished easily, or at all. Maple and walnut floors present certain challenges best left to the professionals. For all other floors, check out whether the floor is suitable.
First, is it a real wood floor? It might be a laminate, to which you cannot apply a sander without destroying the floor. Here’s how to tell: get access to the edge of the floor, either by removing a vent, or taking up one of the saddle boards to look at the raw edge. You can tell if there is a veneer applied. If so, leave this floor alone! Sanding will tear off the veneer, leaving you with an ugly mess.
OK, if your floor passes that test, now see what condition the floor is in.
Hardwood is the perfect wood to refinish, as it can take the punishment of sanding with modern sanders. BUT– if your floor is really old, then it may have been already sanded and refinished multiple times. How much wood is left?
Again, attempt to see the edge of the wood. If there is at least an eighth of an inch of wood above the tongue and groove joints, then you are likely to be OK if you don’t overdo it with the sander.
Any less than that, you may need to consider less destructive, gentler options. Again, this may be best left to a professional.
Alternatively, you might want to look at replacing the floor in its entirety.
Old Floors
Floors in an old house present other issues.
Repeated refinish jobs may have left the old nails close to the surface. If so, you’ll need to sink them well below the floor surface.
Holes will need to be filled. Here you have a couple of options.
For hardwood floors, you might get away with puttying the holes and gaps. You’ll need a wide blade putty knife to get a nice repair. Sand the repair, but know that any imperfections will be evened out when it comes to do the sanding proper.
For larger holes, use small sections of doweling. Pound them to the surface of the floor, and sand them further when you sand down the floor.
What about softer woods, like pine? Here, putty may let you down. You see, sometimes the putty can be actually harder than the wood itself, and ends up standing proud of the surface. Also, putty has been known to come loose from softwood, and actually comes out in little chunks over time.
Best solution: either make a choice to live with the imperfections, or get a professional in. Lots of folks like the weather beaten look of an old pine floor, and you might be one of those. Otherwise, talk to a pro about the feasibility of putting in small laths to renew the damaged portions of wood.
Sanding in Five Steps
Sanding will be done in five distinct steps, each time using finer and finer grits. You’ll start with a 20 to 36 grit, progress to an 80, and finish with a 100. Finally, you’ll attack the floor with a buffer and a random orbital sander.
You’ll consistently use the SAME grit in each step regardless of which sander you are using. So, if you’re using your drum sander with a number 20, ensure your hand sander likewise is loaded with the same grit paper.
First Steps In Sanding
Have ready the following equipment:
- drum sander
- edge sander
- vacuum cleaner
- protective ear muffs
- dust mask
Drum Sander
- safety eyewear
- natural bristle brushes
- foam applicators
- lamb’s wool
- cloths
- a supply of sandpaper in the required grits and sizes
- buffer machine
- random orbital sander
Preparation
Remove any heating grills and electrical fittings in the floor. Look for carpeting tacks, staples, nails and other fasteners, and take these out.
Exposed floor nails? Hammer them down, and then counter sink them.
Vacuum and sweep the floor, and then do a light mopping to pick up stray dust.
Walk the floor in sections looking for loose parts. Repair any loose boards or bad nails. Loose flooring will vibrate like mad under pressure from a floor sander, and will not allow you to get the finish you want.
Now, protect the rest of the house from getting filled with sawdust by draping the doors with sheeting.
1. First Heavy Sanding
The rule of drum sanding is: safety first! Floor sanders are safe if handled correctly, and are a demon if handled poorly. So: protect your eyes from dust, your ears from noise, and your feet from the business end of the sander at all times!
With the first, heaviest grit in place, run the machine with the drum tilted off the floor. Gently lower the drum to the floor until you feel it “bite”. Believe me, you’ll feel it!
Take your time with this. Focus, and start walking the floor in the direction of the grain from one end of the room to the other. Never let the drum “rest”– it will take a chunk out of your floor. Get as close to the far as wall you can, then slowly turn around, and walk back, overlapping the first run by about a board’s width.
You may feel you want to do a “forward” and a “backward” run at each stage. With hardwood, you may do so. With softwood, such as pine, over sanding at this point may take off too much wood surface. Use your judgement. If you feel too much wood is coming off at one time, then go lighter. You can always go back and do a second run. Once too much wood is sanded off, there’s no going back!
The first sanding is just to remove any old varnish or wax. Don’t worry if you do not see raw wood at this stage. This is a rough, first finishing.
Complete this first stage with the hand sander, using the same type grit. Lower the machine to the floor from its edge gently, like lowering a dinner place to the floor starting at the edge. Be gentle, and run the sander in a gentle, curved sweep, either consistently left to right, or right to left, depending on your comfort.
Edge sanding is tiring work, and the machine is noisy and heavy. Rest regularly, and notice where your edging meets the main, heavy sanded areas.
2. Second sanding
Now we smooth out our work from the first sanding. Change to a number 80 grit, and proceed with your heavy drum sander as before. You’ll notice a change in the “feel” of this second sanding. Go lightly at all times.
With some floors, you may feel that this second sanding is not having the desired effect of taking out the roughness of the first. That’s OK. Try sanding diagonally across your earlier work just once. When done, resume going with the grain. You should notice a difference now.
Repeat as above with the hand sander after you are satisfied you have done your best with he drum machine.
3. Third sanding
Now we will remove the imperfections of our previous work. Change over to a number 100 grit, and proceed as before. Go along the diagonal of the floor if you need to, and finish off with the hand sander.
Tip: For an added pro touch, use two or three layers of sandpaper on your edger machine, and go over the entire floor with this. The added layers of sand paper create a “cushion” that will allow you to work over the finer imperfections in the floor. This is the last major sanding, so have everything in your favor so as to get a beautiful surface, ready for staining.
4. Get The Best Out Of Your Buffer
Load your buffer with a number 100 sanding screen. Work the floor evenly and slowly. The idea is to get a smooth surface you can varnish, stain, or even leave “as is”. Take your time, and never hurry.
5. Final sanding
Using a random orbital sander, go right up to the baseboards, door frames and smooth out all differences between the edges and the main floor.
A random orbital sander spins the sanding disk in a circle, and at the same time moves the entire rotating disk through an elliptical shape. This ensures that the sanding surface never sands the same patch twice, and leave no scuffs, abrasions or grooving.
Your Choice of Finish
Common ways to coat your floor include polyurethane, either water or oil based. These come in a range of “finishes” from glossy all the way to various satins.
Satin looks best on floors that are not absolutely perfect. So, unless you have done a truly professional job, go for this option. Glossy floors with obvious faults don’t look too well in the end.
Oil based polyurethane stinks terribly, and its fumes are toxic. The water based choice is a little safer to use, and does not smell like a hazardous chemical spill!
Other choices include waxing, or leaving bare.
Using a natural bristle brush or foam applicator, apply your stain evenly, working to the edge in thin layers. Work out any brush marks before it dries with lamb’s wool.
Allow each coat to thoroughly dry before applying any further stain. If at any point the grain has “raised”, you’ll need to sand between coats. This is pain in the neck, but there’s no way around this. After a sanding, gently dust mop the floor and let dry.
