Question:   …………… The home has hardwood oak floors throughout the first and second floors. The bungalow was built in 1929, and the floors are probably original. They have been refinished before but seem to be in good enough shape to sand and coat, that is to say the boards are not overly thin by my estimation. I think the only real problem is that there are some large, long gaps especially on the first floor but not exclusively. Some gaps are as much as a 1/4 of a inch. Also, as I had mentioned in my previous e-mail, the gaps, on the whole, seem to only appear every five courses, that is to say every five boards (the boards are typical width, not wider than I’d say 3 inches). I know that the fluctuation in temperatures and especially humidity play a large roll(we live in New England, Rhode Island, USA), but do I have any recourse……………….. Kevin Answer: Dear Kevin A home built before WW II would have wide pine planks as a subfloor. They were installed “air dried”, when the house was built. If a good builder had planned for a hardwood floor on top of this pine subfloor he would have laid the pine planks on a diagonal to the floor joists. But in a lot of cases the house would have been sold without the hardwood, and in this case the builders back then would have installed a tongue and groove pine plank at right angles to the joist. And later the first owners would have installed hardwood strip floor on top of the pine boards. The mistake that the hardwood mechanics made was to install the hardwood in the same direction as the softwood subfloor. So, even though the hardwood was kiln dried the subfloor boards would have begun to do their final drying only as the house was heated over the first winter. As the pine subfloor shrunk, it would have caused larger gaps in the hardwood nailed to it. And it is very typical that this would happen every 5″ corresponding to the width of the pine boards. So, there is no way of getting that floor tight again, except to remove the entire hardwood floor, renail the now loose pine subfloor back to the joist and re-install the old hardwood, or install a new hardwood floor. And this time the new or old floor will need to be installed opposing the old pine floor boards. I’ll take a little excerpt out of the “squeaks article” to show you how to do this now. ………………..You remove an old floor the opposite way it went in. Start at the far end of the room where the last few boards were laid. They will have their tongues pointing toward the wall. The last 2-3 rows will be face nailed. You will only have to crack one board in half ( with a chisel and mallet ) in the last row to remove it. Then use a cat’s paw restorer at http://www.leevalley.com/wood/page.asp?SID=3D&ccurrency=3D1&page=3D32014&category=3D1,43456,43399 This tool will gently remove the boards without damaging them. Try to scoot the thin edge of the catspaw under where the floor is nailed, and pry just a little at a time. Once you work backwards into the room and get some maneuvering space you can use a larger tool : http://www.leevalley.com/wood/page.asp?SID=3D&ccurrency=3D1&page=3D32015&category=3D1,43456,43399 The renovator bar will ease up the most stubborn boards. Once you have the whole floor removed, re-nail and repair the subfloor, so that when the hardwood goes back, it will be squeak free. Re-nail the subfloor with the spiral spikes that are at least 3 times the thickness of the subfloor. A one inch thick pine plank subfloor needs 3=94 nails to refasten it to the joists. A subfloor board 4-6=94 wide needs two nails on EVERY joist. Wider subfloor boards need 3 or even 4 nails to firm them up. This is the last chance you have to fix the subfloor……………………. So, Kevin this is the best way to deal with this floor, but if this seems too daunting you could try to save the floor as is. First you will need to renail the hardwood floor back to the joist, to keep the floor from moving. This is because I’m going to suggest you slurry fill the floor. So I’m going to send another excerpt from that same article on how to re-nail it first : …………….Once you have marked out all the joists with the chalk line, determine which side of the hardwood strip is the tongue side. You will want to pre-drill or nail spin a 3″ spiral finishing nail, so that this nail goes through the tongue side of the hardwood floor board through the subfloor, and penetrates the joist quite solidly. Nail spinners are a must and are available at www.leevalley.com ; Prod. #99K20.01. The nail should be spun in at about a 45 degree angle, the same as a new floor installation. This 3″ nail should be only used for 3/4″ thick floors, use shorter ones for thinner strip floors. A 2 1/2″ nail should be used for 1/2″ and 3/8=94 hardwood strip floor so as not to crack the tongues. The nail spinner works wonders for this application,I don’t do repairs or installations without it. But be sure to use the spiral type nail in this use…………….. Now once the floor is solidly renailed you can slurry fill the floor.There would be about three choices of the filler. The best and longest lasting would be a good quality oil based polyurethane varnish mixed with fine maple floor edger sanding dust. Now the key here is the dust, is has to be very light in color (maple is best) and very fine like talcum powder (and clean). You might persuade a local floor mechanic to sell you some. But as he may save it for his own jobs it may be hard to find. The next best mixture is the red oak floor edger dust and lacquer finish mix. Not quite as flexible but faster drying and easier to find the dust. And the last choice would be those pre-mixed filler buckets meant for hardwood floor filling. This is the worst because of the poor adhesion to the floor gaps, and will in most cases crack out in just a few years. But it’s available at most wood floor trade shops. So in any case, trowel in this filler across the whole floor, and for the poly based, wait a week for it to dry and then have the floor sanded professionally. But do the finishing yourself. Finish with oil based poly as I describe in the “Applying poly without the bubbles” article. The lacquer/dust mixture will dry in two days, and be ready for resanding, and the water based pre-mixed should dry over night in a warm house. I use a steel drywall trowel and go over the floor twice when filling. On a really rough old floor I will do the coarse sanding first then the slurry fill, but this may not be needed your case. Try to remove most of the excess filler from the surface as you trowel so you the floor mechanic doesn’t have a hard time sanding it off. Some filler will pop out during the sanding process. But only with the lacquer and water base can you touch up the filler as you are sanding (they both dry fast) The poly/maple dust will turn a little darker than the floor, but you can lighten it as you are mixing it by adding whiting (powdered chalk), and some universal tints. The lacquer/oak dust is about the correct color, and the water based filler come in a few pre-mixed colors, but choose one just a tad darker than the final finished color of the wood. You can determine what the final floor color is by sanding the floor to the bare wood in a small area, and splashing some paint thinner on the exposed wood. Try to get the filler color right, or you will have a really striped floor. This would be a good project for about mid spring when the floor is at it’s mean EMC (equilibrium moisture content). Once you have the floor filled, sanded and finished try to keep the RH indoors within a narrow range (40-60% would be ideal). Air condition in summer or heat and humidify all winter to achieve this and the filler might stay in. It’s important to keep the basement or crawl space in the same RH, then neither subfloor or finished floor will move. Do Not try the glue and sawdust filler, or glue and stained rope filler, as suggest by some pros. You should never have the wood floor edge glued in any way, as this will tear boards in half during larger humidity shifts. I know I’ve seen it happen. Sorry to take so long but I thought I would show you all the methods from best to worst. After all you paid for it. Any more questions you may have on this subject or clarifications of your original question feel free to write again at no cost. I hope you have enjoyed this personal service, real human responses are the best. As always your Most humble servant, Joseph, the Wood Floor Doctor.

Question: We are removing a wall between two wood-floored rooms, as well as a closet and corner hutch. A lot of wood flooring–probably about 30 sq. ft. or more, will be needed to repair the floor. The flooring is probably about 25-50 years old, B grade oak tongue & groove flooring, 2 1/4″ wide, and the remodeler says it will be hard, if not impossible, to find flooring to match it with the right t profile. Can you give me any suggestions? Thank you, Kay Answer: Dear Kay I find it funny that your re-modeler said that this size and grade of oak flooring is hard or impossible to obtain. As long as you are talking about 3/4″ deep by 2 1/4″ tongue and groove red or white oak floor, this is just about the most common and easily obtained hardwood flooring in North America. I’ve got my eye on 5-6 pieces of this wood as I speak, scraps and sample boards, I use this stuff ALL the time. Maybe they just want to sell you a new floor, ya think ? Anyway, it’s not such an easy repair, and most carpenters don’t have the years of experience to deal with this sort of thing. Oh, and first there is no such thing as B grade. There are about 4 grades of hardwood. The top grade is clear and select quarter sawn. The next is select and select and better. And the last two grades are Common #1 and finally Common #2. What I have found in my 25 years in the business is that a lot of dark and mineral streaked boards that used to (20 years ago) be included in the Common grades is now a great part of the Select grades. So I find that can use a Select grade Oak to repair an old oak Common grade floor, by just choosing the darkest pieces in the new wood bundles. So first here is a picture I just took of the oak flooring grades as set out by a trade organization called NOFMA. Once you have selected the grade that most closely matches your old floor, the next problem you might have is to repair the rooms so the floor appears to be one room. If you are very lucky the two floors will have been installed in line with each other. Use a string line and stretch it across the two rooms right on the seams of the boards and see if they line up reasonably well. They may start in alignment at first, but you will find that the farther the rows go into the room, the more out of line they become. If both rooms happen to be in perfect alignment you can repair the floor, by staggering in the new floor, as described in my repair article in the Hardwood Authority section of this site, and illustrated by this picture. But as is often the case, the two floors are only half out of alignment, there are two solutions to this. One is to remove about half the wood flooring from one of the far section of one of the rooms. Remove it carefully prying the tongue side of the boards just under the blind nails. Choose the quarter section (of the new big room) that is most out of line. Clean up the boards and re-install the old flooring by staggering the joints with the new floor, as they should be exactly the same size. If that all sounds daunting there is a easier and quite neat way of installing a “header” piece all the way across the opening of the two floors. Set a fine bladed circular saw ( we have specialized plunge cutting saws for this) and using a straight board as a saw guide cut two lines a right angles on the ends of both floors. Make sure the two cuts are parallel with each other and are a little less that a multiple of 2 1/4″ apart. Install the new wood in this channel at right angles to the old floor, and Bob’s your uncle. Here’s some more illustrations. This last repair was done to a re-modeled closet and once sanded and stained and finished, it came out quite neat, and was a economical and interesting way to fix the floor.

Question: Hello Doc: Thanks for having this site on the web. Here’s my situation & a couple questions: We’re doing a remodel & I know I definitely want a sand-on-site floor (the engineered hardwoods just don’t look authentic to me). My decor is genuine art deco from the 1930s and 1040s & I really would like the finished flooring to look like it came from that period as well. Do you have any suggestions as to what type of wood & stain was used primarily back then? Also, we’ve been told by 2 dealers that hardwood cannot be laid on top of particle board because the hardwood will lift, yet, we’ve been told by 2 other dealers that there won’t be a problem with lifting if 2″ nails are used! We’re very confused & really need and appreciate your guidance. Thanks – Yvonne Answer: Dear Yvonne The first question is best answered by the book Elements of Style Encyclopedia. The section I have just opened to is the 20’s and 30’s and describes the floors that were in fashion during that era. Art deco was predominant in the 20’and 30’s. While the modern era came in the 40’s. According to this book parquet flooring was quite popular, this included the herring bone pattern. Some French style boarders and inlays were done on the edges of strip floors. All wth the emphasis on straight lines and complex geometric patterns. If you can get the book it is on page 431. Inlaid linoleum and terrazzo was most popular in this era, for kitchens The colors of the wood floor were blonde or very light brown stains. The darker stained floors were really part of the Victorian era, just before this. So in general lighter woods were most common floor colors. but darker wood boarders were often done even then. Again to emphasize simple but elegant geometry. If you cannot get the book, I could photo copy the two pages and send them on to you. Oh, and now for the particle board dilemma. the first two guys are correct. A subfloor consisting of OSB, chip board, flake board, or particle board, makes just about the worst nailing surface for a hardwood floor. These types of sub-floors have the worst long term nail holding and moisture stability problems. These really show up when a hardwood floor is nailed to them, and seams open up in the hardwood due to the shifting subfloor. You really must remove it and replace it with 3/4″ plywood. I’ve got the University studies to prove everything I say. The two inch nails are just the standard nails we use in the flooring business, they will not improve matters. Never have any installers use staples for the hardwood floor. This will crack the tongues. I hope you consider a donation to the site, and I would be glad to be of any more help. If you found this information helpful, please explore the Wood Floor Doctor.com by visiting the rest of our website. As always your Most humble servant, Joseph, the Wood Floor Doctor.

Question: I have an old hardwood floor that I need to refinish. The sides have been poly’d but the middle is unfinished. I’m trying to avoid sanding because my children have asthma. Any suggestions on a product that would do the same as sanding? Answer: Dear Melissa No, sorry not really. You won’t be able to imitate an old aged finish in the middle, and it will stick out like a sore thumb for years. Best to bite the bullet and sand the whole floor and finish it with 3 coats of an oil modified polyurethane like Fabulon (no lacquer sealers please). Or if you want to try a fairly safe (but new) water based finish read my article on the Dura Seal 1000 available in the search box at the top of this web page. Make sure you hire a pro for the sanding, but you could do the finish yourself. I don’t think you will get very even results but chemical stripping may be worthwhile. Please read my article on this subject also found in the available in the search box at the top of this web page.

Question: I have several questions. I am refinishing my floors myself and am now having to re-do them because of some problems that have come up. First of all I live in an apartment that was built in 1927 so needless to say the floors are old and a little creaky. I don’t know when the last time was that they were refinished but it was more that 10 years ago. The old finish was over bare unstained wood, a matte finish, was very ambered, hard as steel (almost impossible to scratch and impossible to scrape off) and was very hard to get off. Since I am unable to move out while doing this I am doing the floor in sections. After sanding and staining the floor (to get a deeper color the stain I stained it a few times) I finished it with Minwax oil base polyurethane (it said great on floors). After a few weeks I notice that in various spots where the planks of wood butt up against each other that the finish was lifting off the wood about 1/16th of an inch at the seams. In the spots were this is happening is where the seams of the floor bend slightly as you step on them, it is not happening anywhere else nor is it happening in the center of a plank. The Minwax was not very strong because in these areas it will chip and scrape off very easily. That never happen with the old finish that was on there, how do I keep that from happening? I then switched to using Harco moisture cure urethane to get a stronger finish. I tried using the semi-gloss without and with a retarder and no matter how much I stir it I always end up with an uneven sheen mostly at the lap marks (the lap marks being glossier). I am giving up using this stuff but I am very curious how to achieve an even sheen. Finally, since I now have to re-do the whole apartment I would like to know which brand of oil based polyurethane you recommend using that will give me the strongest finish in semi gloss and what type of finish you think may have been on my floors before. Thank you, Alex Answer: Dear Alex Your first mistake may have been that multiple stainings. Stain contains a binder agent (like glue) that may not have dried properly with this multiple applications. You would have had to wait 24 hours or more between stain applications. I use a better stain brand like the Dura Seal stains when I want a really dark color. Their coffee brown is very dark and rich, and one application always does it. You also may not have waited for each coat of poly to dry, and you may not have scuff sanded thoroughly between coats. I never use the Minwax brand, and prefer the Fabulon brand heavy duty poly instead. The dry times listed on ALL these finishes are WAY too optimistic, and I always let stains dry at least 24 hours, and wipe my hand on them to check for transfer. I also smell the stain, to see if it has lost all solvents. I BRUSH on the first coat over the Dura Seal stain carefully, and let it dry 24-48 hours. The test for finish dryness, is to screen or scuff sand and check your screen for any gummy transfer. Also smell the floor, any solvent smell and wait another day. I would never recommend a moisture cured poly for residential use. The toxins in that finish are most awful. You are severely poisoning yourself every time you use it. It’s for industrial use only. And they will never perfect the satin flatteners in this type of finish. We only use gloss, with MC poly. The Fabulon Brand has a very reliable satin or semi gloss finish poly that I use all the time, with great results. But I brush the finish on, I never use lamb’s wool applicators. No bubbles and an even sheen is my result. And happy and paying customers also. So my advice for peeling finish, is to have the floor professionally sanded again and start all over with the finishes and methods I suggest. You will get a more consistent result by sanding all the floors in the house, staining all at once and finishing all at once. Store your furniture and bite the bullet, and hire a pro at least for the sanding, but you certainly can do the staining and finishing of the floor yourself. Oh, and don’t expect any oil modified poly to cure until a month has gone by. And, very old finishes are harder due to the fact that they continue to cross link throughout their life, until they finally become brittle and crack. This takes about 40 years, so don’t worry about it.

Question: I have just bought a house, built in 1935. The flooring throughout is tongue and groove pine. My husband and I would like to refinish it ourselves. What are the steps? Answer: Dear Amy Suffice to say I cannot teach you how to sand a floor by email. And I doubt that the rental places will give you a course on sanding and finishing your floor. The “toy ” floor sanders they rent at all the tool rental shops will not, in any case, do a decent job of sanding your floor. But before you consider sanding, read the second part of the floor maintenance article available in the search box at the top of this web page, there are many alternatives. Also read the chemical stripping article in the same section. I strongly advise you hire out the sanding part of the job. Nobody I know that has sanded their own floors will ever do it again. In most cases they have used far too much time and sandpaper. Then the results were from barely passable in low light, to downright butt ugly floors. The problem with DYI floor sanding is one, the machines, they are light duty, and will leave pronounced chatter marks in your floor. And two, the machine operator, who has little or no training to pass this machine smoothly and evenly across the floor. Most of the mistakes are made in the first passes with coarse grit sandpaper, and these cannot be removed with the fine paper. The amateur does not recognize thing are going wrong until the finish is applied, but by then it’s too late. Pine is very soft, and unforgiving so one slip and your old floor may be gouged forever. Even a lot of pros have problems sanding and finishing this wood. Best to have it professionally sanded, and then consider doing the 4 coats of oil modified polyurethane yourself. Be sure to read my article available in the search box at the top of this web page, on how to hire contractors. When viewing a contractors past work, be sure to see his pine floor jobs. And if you need advise on brushing the 4 coats of poly, I’d be glad to help you further. Just ask. If you wan to see a good video on floor sanding, please looks at the reviews available in the search box at the top of this web page.

Question: We have 90-year old Pine floor that has never been touched or finished. After we clean it up what should we do to finish it? Looking for a couple of ideas. Thanks, Craig Answer: Dear Craig Please read the floor maintenance article available in the search box at the top of this web page, it should say it all. I’ve never heard of a floor that’s 90 years old and hasn’t been touched or finished.

Question: Our hardwood floors are 4 years old. Something caught fire in our house and small parts of the floor got burned. A well meaning guest sanded the burn out leaving spots where the finish is gone. The wood is undamaged. How do I get rid of those sanded spots? Answer: Dear Jane You don’t get rid of them, you apply some finish to the spots. Contact your floor company who did the floor 4 years ago. They should have a touch up kit that they can sell you even if this is a prefinished floor. You didn’t say but if the floor is stained, you will need to match the stain first before you re-coat the spot. Don’t expect the floor finish (if it’s polyurethane, again you again didn’t say) to blend in well. But if you re-coat the spot with several coats of the matching finish, and then re-coat the whole board or group of boards, it will be passable. It should look OK until the whole floor needs recoating then it will certainly blend in quite well. All wood floors need re-coating every 5-10 years, read about this in the article available in the search box at the top of this web page, the maintenance article. Or if it’s a prefinished floor (half of you out there have them) you could actually replace the burned boards with ones that exactly match your floor. If you want to do the repair yourself, read my article available in the search box at the top of this web page. Oh, and if plan on touching up only, make sure the spot have been sanded smooth and level. Use 80 grit sandpaper to remove the burn and level the spot. And then 100-120 grit to take those marks out. Then attempt the touch up. I cannot tell you exactly what finish to use because I don’t know what’s on your floor. I can’t see it from my desk here.

Question: My mother grew up mopping floors with pine disinfectants. I installed Bruce prefinished flooring in her home a couple of years ago. Needless to say I told her not to use water to clean her floors, but she did not listen. Now the flooring has become grainy in texture and dull. Since this is a laminate floor product, how would I go about refinishing them. I was told this could be done up to 3 times. I can’t seem to get the information even at Bruce’s homepage. Can you point me in the right direction? Answer: Dear David You must mean laminated or engineered wood floor, laminates are vinyl. If and only if the floor has at least a 1/8″ top veneer layer can you POSSIBLY sand it once. If the floor is reasonably flat you MIGHT find a professional willing to chance this sanding. You see, he has to sand off the beveled edges as well as flattening the floor for the first time. So the ability to sand this rather thin veneered floor is limited. I guess it also depends on how well the installation was done. It can only be judged in person by an honest pro. Find one. If in the other hand it is a thicker 1/6″ veneer layer you should have no worries, by all means have it sanded and refinished at least this once. Make sure they use a finish that is easy to re-coat. I would suggest you apply 3-4 coats of a good quality oil modified polyurethane. Use no lacquer sealers !!!! Water based finishes are out, they may further damage the veneer. Be SURE to read my floor maintenance article inthe Floored News section, and before you hire someone read my Hiring Contractors article in the Hardwood Authority section of this web site. Oh, and if you have the thinner veneer, and the pros refuse to sand it, consider chemically stripping it instead. Read my article on this subject also in the Floored News. Once all the old finish is off, you may be able to smooth the floor with an Orbital Floor Sander (article on this in the Case In Point section) and finish it with 3-4 coats of OMP. This last method may not work well if the floor is a waxed prefinished product (you didn’t say). It’s very hard to get all the wax out the seams, and this will interfere with the new finish. As always your Most humble servant, Joseph, the Wood Floor Doctor.

Question: My refinished floors won’t dry Completely. I’m using Minwax. High oil polyurethane and its been 3 days. What’s happening? Answer: Dear Dan Right now you should add some heat to the area, by either space heaters or turning up the house thermostat to 75 F. And get a large fan to blow across the area. If the poly hasn’t dried in 12 hours it has lost it’s ability to cure properly by now. But in order to tell you how this happened I need to know a lot more about what sort of floor this is. What species of wood. Did you sand the floor yourself ? Was it white and clean after the sanding ? Was the floor heavily waxed in the past ? After you sanded it did you stain the floor, and what was the brand of stain ? What was the weather like when you applied the finish ? Is the floor built over a heated basement or a crawl space. And lastly what was the timing of all the coats and stain ? If you can answer all these question, I can most likely tell you what went wrong, and if the finish is savable. In the mean time, ventilate, and warm the floor. And do a test with that finish on a new piece of wood, to see if the finish is a problem. Just apply one coat on the test board. I have had this happen to me in the distant past, and I can tell you now it is rarely a problem with a bad batch of finish. As always your Most humble servant, Joseph, the Wood Floor Doctor.