Are you up to sanding and refinishing your own hardwood floors?

Are you good handling machines? Do you have a lot of patience? Do you have a strong back? Sanding and refinishing Hardwood flooring is not for everyone and is certainly not for the faint of heart, sanding and refinishing hardwood floors is time consuming, finicky hard work and the cost of renting the equipment needed to perform the work along with buying all the sanding paper and finish is not inexpensive. This is not to say that you should not try after all, over the years it’s been a popular DIY project to do and most all home centers and rental stores have floor sanding machines available to rent.

If the above does not scare you then it might be worth the time and effort and you might even save some money doing it yourself. DIYers who may only do this job once in their lifetime jump right in with both feet and most get frustrated with the final result.

Old carpet removal

If the hardwood flooring is covered by old wall to wall carpet the easiest way of removing it is to use a pair of pliers and start from a corner of the room and pull the carpet up and away from the thin barbed wooden (tackless) strips that hold the edges of the carpet down. As your pulling the carpet free from these strips fold it over and cut the back of the carpet with a utility knife into easy to manage 3 to 4 foot sections. Once the carpet is removed you will have to also have to pull up the old carpet padding.


Once the carpet and pad are up off the floor you will need to remove the wooden carpet strips that are nailed down along the edges of the hardwood flooring. To avoid the frustration of splintering these strips into a thousand pieces do not try to pry each nail out, use a thin flat “wonder bar” and tap it under the wooden tack strip under each nail that holds the strip to the hardwood floor and just pop each nail loose, start at one end of the strip and work your way to the end where the whole piece should be lose enough to be easily removed by hand. Use heavy thick gloves when handling these carpet tackless strips as they have extremely sharp barbs.

If there is no wall to wall carpet to be removed it is still advisable to check the entire flooring for any nails that may have to be counter sunk and filled prior to sanding the flooring.


Now that the Hardwood floor is exposed you will also notice hundreds of staples left within the floor from the carpet pad. The easiest way of removing these staples is to either pull them up with pliers one at a time or to save time use a flat square faced shovel and scrape the surface of the hardwood floor, the sharp front edge of the shovel will usually grab the staples and pull them out of the floor as you force the shovel along the flooring. The sharper the front edge of the shovel is the better it will grab and pull the staples out of the hardwood flooring.


Once all the staples are pulled up go back over the floor and check for any staples or nails that you might have missed then vacuum the whole floor carefully and counter sink any exposed nail heads with a nail set and hammer. Fill any holes in the hardwood flooring left from the nails in the carpet tackless strips that was around the edges of the room using colored wood filler that will match your final floor color. The small staple holes left are generally to small to be filled and are in most cases better off left alone.


Prior to sanding and refinishing the hardwood flooring

You will want to make sure that you take the proper precautions to protect other areas of the home that are not going to get done. Aside from moving everything out of the rooms that are to be sanded and refinished make sure you seal off doorways with weighted cloth drop cloths to keep any dust from blowing in to areas you don’t want it to go. Dust and some finish fumes are flammable so make sure all Gas Appliances are turned off to prevent fire.

Since the sanding machines make a lot of noise think twice about having your family and pets stay in the room below or above where you’re going to be working it is really best if they are away until the job is completed and the finish dries. Cover all Fire alarm sensors with blue painters tape as any dust that gets in them can set them off and remove the tape as soon as the work is done for the day. Even though the machines pick up 90% of the dust we use 20” plastic box fans bungee corded into a window exhausting any interior air outside to help control any airborne dust. The window on the opposite side of the room should also be opened to allow fresh air in. During the sanding and refinishing process it is also advisable to wear protective ear plugs and dust masks.

What you need to rent

Professional large drum sanders (shown below) that weigh approx 250lbs. run off a dedicated 220 volt electrical line, generally are not available to rent. The smaller more light weight (150lb) drum sanders (shown to the left) you find at rental stores run off of 120 volt wall outlet but the machine should still be plugged into a dedicated 20 amp wall outlet like an air conditioner or refrigerator so that the sanding machine will not keep tripping the breaker once the sanding starts. These 120 versions have smaller motors and take longer to sand the floor than the larger heavier professional 220 volt models but are lighter for the DIYer to lug around.


There are three different drum sander versions found at rental stores each has their own methods of loading the sand paper sheets onto their drum. The first method is where you wrap the sandpaper sheet around the drum and slide the ends into the drum slot where you use a wrench and turn the two cams that are on the side of the drum in the opposite direction which draws and tightens the ends of the sandpaper together locking the paper on the drum. The second version there is a narrow metal plate that you screw on that clamps both ends of the sandpaper to the drum. The third version is only found on the newer drum sanders where the sand paper is a round sleeve that simply slides onto the drum where you then simply raise a lever that tightens it on.


Drum sanding the hardwood flooring

Older type drum sander rental models use the tilt method of operation to start sanding, where you lift the whole handle to tilt the machine up and the drum makes contact with the floor. Newer drum sanding versions that have one piece sand paper sleeves have a lever that you can gradually raise and lower the drum up and down to the floor. These newer drum sander versions are easier to handle and will give you better results.

The second type of drum sander is a much larger 250 lb. 220 volt that professionals use. These types of larger drum sanders plug directly into a 220 amp electric stove or clothes dryer. These professional drum/belt sanders sand the floor quicker and in most instances give you a smoother blemish free finish then the lighter rental types.

The sandpaper is loaded on the drum by either wrapping it around the drum and sliding the ends into the slot where you turn two cams that tighten and hold the paper to the drum.

Or in newer belt versions you lower a lever on the side of the machine and slide a sandpaper belt onto two drums which separate and become tight when the lever is raised.


With either the rental of professional type drum sanders you will usually need to use three different grits of sandpaper. Starting with coarse 36 grit sandpaper for your first pass over the floor which takes off any old finish and removes any deep scratches, then you would use an 80 grit which removes any remaining scratches and old finish and smoothes the rough sanding marks made with the 36 grit paper. You should make a 3rd and final pass over the floor using 100 grit sandpaper which smoothes up the surface of the wood even more. Always unplug the machines when changing the sand paper or empting the bags.

When running any type of drum sander it is critical to have the drum raised up off the floor when turning the machine on and off. When you are ready to start sanding move the machine forward slowly, gently easing the drum to the floor, keep a slow steady pace. Stopping the drum sanders motion while the drum is sanding the floor will create deep gouges in the hardwood flooring. You must also start easing the drum up slightly when getting close to walls and gently lower the drum back to the floor when pulling the machine back on your return sanding pass. In other words you walk the machine down to the wall and pull the machine back wards all the time sanding the floor. On the return pass walking backwards you slightly move over half the width of the drum then continue again forward.


Always work two thirds of the room, then when one side is sanded turn around and sand the other half making sure you overlap where you started in the middle by 2-3 feet blending the areas. And unless you want to experience the end of the world DO NOT RUN OVER THE CORD. Work away from the cord keeping it to your side behind you.


Edging the room

When the Drum sanding has been completed the next machine you will need is called a floor edger this sander sands along the edges of the room and in any areas that you could not get the larger drum sander into such a hallways and closets. The same 3 grits of sand paper should be used. When using the edger you want to hold the machine firmly and gently try and run it in the same direction as the grain of the wood, smoothly blending out onto the area where the drum sanding stopped. Pay close attention to eliminate any coarse sandpaper marks in the wood with the final pass using 100 grit paper.


To change the paper on an edger you will lay the machine on its side and use the special wrench to unscrew the center bolt that holds the paper on to the edger plate. To prevent accidentally hitting the on switch make sure that you unplug the edger from the wall while changing paper or when emptying the dust bag. Floor sanding edgers are available for rent at most rental stores.


Scraping the corners

Once the edging is complete you will need to use a long handle paint scraper to hand scrape the corners of the room. Occasional sharpening the blade with a number 8 file will be needed. Hand sand with the grain of the wood using 100 grit sandpaper after each corner is scraped.


Final sanding of the room before the finishing

Once the hardwood flooring is free from old finish and any old scratches then it is time for the final sanding which is done using a rotary floor buffer that is set up with an attached pad. This special pad holds in place a circular disk of fine grit paper I recommend using a 100 grit screen. Pay close attention to carefully blend in the edges of the room into the rest of the room. Operating this machine is a lot like trying to tame a lion on a leash. If you raise the arm of the buffer up the machine will fly to the right, if you lower the arm it will swing to the left. A fine balance in the middle is needed in order to control the machine. I suggest testing the machine in the middle of a large room first to get the hang of using the buffer then final sand the whole floor.


Another type of machine available for putting the final touches sanding the floor is an orbital vibrating sander that is about the same size of the rotary flooring buffer but is easier to handle, these machines although a slower basically start up and vibrate in place. To move it around you simply pull and push it where you want.


Once you think you completed the sanding look closely at the floor again for any fine scratches, swirl marks, gouges or rough spots that will get magnified when the finish goes on. Hand sand them with 100 grit sand paper with the grain.


Vacuum the entire room thoroughly including walls baseboard shelves etc. doing so will ensure no dust gets into the finish.


Applying the floor finish

There are two basic types of floor finish available either a water base formula or an oil base finish. The Water base finish has virtually no odor and dries within an hour or two per coat, personally I would not apply more than 2 coats a day to ensure each coat dries properly. Since the water base finishes leave a thinner film finish I would use 4 coats to get a proper look. You can use a 4-5 inch wide nylon bristle brush to apply water based finish. Or if your going to use 3 coats of Oil base urethane use a pure china bristle brush. Apply the finish with the grain of the wood and in small sections across the floor.


It is always advisable to cut in a sections of the walls using a 4 inch wide paint brush and you can continue to apply the finish in sections across the floor with a wider brush but If available to you, use an 18 inch foam applicator that you can snowplow the finish evenly across the hardwood floor in sections, it’s easier and faster than brushing the finish on the whole floor.

The first two coats of finish will raise the grain of the hardwood flooring so you need to “light” sand the first and second coats lightly and evenly after the finish has dried. Do not sand through the coats of finish to the hardwood flooring. Using a used 150 or finer grit paper works the best. Each coat must be vacuumed thoroughly between coats of finish. You choices for finish sheen are Satin – Semi gloss and Gloss. If you want a Satin finish sheen use two coats of gloss first then the final coat of Satin otherwise the floor may look cloudy.

Once the floors are completed and dried you should put protective chair glides on the bottoms of all furniture to protect them from being scratched.


IMPORTANT SAFTY TIPS

  • Always wear Safety glasses, Ear protection and Dust masks.
  • Always unplug any machines when changing paper or working on them in any fashion.
  • Empty the dust bags frequently outside, store plastic bags of dust outside away from any wood frame building as they can ignite.
  • NEVER have any open flames near dust bags or finish.
  • Never attempt to hook up a drum sander to the main fuse panel hire a licensed Electrician.
  • Turn off all Gas Appliances.