This video provides a step-by-step guide on how to repair a damaged subfloor in just minutes. The video starts by identifying the cause of the gap in the subfloor, which may be leaks or lack of ventilation. Then, fill the gaps using wood fillers, caulk, or expanding foam. Non-shrinking, somewhat flexible wood filler should be used as if you were finishing drywall. If there are any ridges or other imperfections, sand them with a random-orbit sander after good cure.
To fill large gaps in the subfloor, move floorboards close to each other and see how much space is left around the edges. If it’s over ⅛-inch, add more. For joists with less than 1 inch of rot, scrape away any rotted wood and fill the space with epoxy. All epoxied joists should be brushed with a few coats of wood preservative.
Cement-based caulk or self-leveling compound can be used to fill small gaps in the subfloor. Wood strips, precut wood shims, or rope can also be used to fill gaps before. If a void is found, fill it in with an epoxy-woodflour mixture. Apply wood glue around the edges of the opening you routed and press it into the wood.
If the subfloor is bad, locate it under the house and add lumber to resupport the area from underneath. Use an orbital sander to smooth the floor out, add additional screws through the plywood into the joists, patch and level, and lightly sand the hole. Use a trowelable floor patch on the damaged areas to get a reasonably smooth surface and cover with 1/4″ APA rated underlayment, glued and screwed or covered.
📹 How To Prep Wood Subfloor for Luxury Vinyl Plank Flooring for Beginners. Fix High and Low Spots!
When I removed the old tile in the kitchen and dining room I exposed some high spots and lows spots in the plywood subfloor I …
📹 How To Fix Soft Subfloors (The Easy Way)
Need Answers or Advice for your DIY Project? BECOME A DIY MEMBER NOW!
Depending on how thick or thin your LVP is, that padding could make the LVP sink down and shift causing the seams to wear out over time. I used a thin plastic vapor barrier underneath my LVP for those reasons. I’ve been in a house that has used a thick padding underneath, and with every step you could feel the floor sink in a little. But if your LVP is thick and wide, you should be okay.
Putting underlayment under lvp with a padding attached is not a good idea. The squishy nature of it can break joints. If you have to bring something up to level use thin plywood glued and screwed. Also dont use mdf in subfloor repairs, even with plastic under that piece moisture can wick from surrounding boards in the summer and swell mdf up and ruin all the work to get it flat. Glue and screw plywood and forget the plastic. Very thorough prep though, good job!
I’ve heard two different philosophies on the direction any flooring should go. One is to be directly coming out of the front door and the other is to go out from windows. According to both of these, your flooring should go the opposite way you’re planning to lay them (based on the direction you laid the underlayment). It was interesting to see this process. I have a big dip in the foundation where some LVP was put in by the previous homeowner. I don’t know if they did it themselves, but every time I walk over it, I can’t believe they didn’t do anything to level the base.
Looking forward to the flooring. It’ll probably be the biggest change yet. But Mike, listen…. you really need to change the drawer/cabinet faces on that one oddball cabinet. It sticks out like a sore thumb and makes it look cheap. You can order custom made doors online and they’re not too terribly priced. I altered a cabinet in my house an it was cheaper/easier to have a new door made for it. Frankly, it’s the best quality door in the whole kitchen (but matches). This would set off my alarm bells if I was looking at the house to buy. If I see that, I’m going to start looking hard at other things.
This is super helpful! I’m prepping to put down vinyl plank flooring and my concrete floor is really uneven. I tried using Sand Topping Mix to level it out, but it wouldn’t come close to feathering. I had to scrape it all up before it dried and discard it. That Henry UniPro looks like the perfect solution! Thank you!
OK…I have a question for the peanut gallery….. What are your feelings regarding the ‘LVP’ flooring. I’m not asking about colors, I’m asking about the product itself. If you were doing a ‘luxury’ home, is it something you would use? If you were BUYING a luxury home, is it something you would be happy to see? Because I have to tell you folks; my answer to both questions? Is ‘NO’.
I guess woodworking/home reno stuff is no longer Mike’s top interest. He’s been making something cool and new every week but this income property series seems to go very slow. We all miss when he was so enthusiastic about making stuff so we all waited for his next articles. However, I don’t blame you. I hope your new priority is also making you stoked.
My vinyl plank is coming up everywhere… not the best install for sure. I can feel a ton of low spots and that’s where it’s coming up at the seams. This is a rental home, so I’m not sure if the landlord is supposed to fix it or myself. I honestly feel like I could do a better job than this and I’ve never installed vinyl plank flooring. Oh and BTW one plank came up so I checked underneath and it’s the original subfloor. No underlayment or prep work like what you’ve done in your article. I’m open to suggestions.
What should I use to level out flooring that’s pretty messed up, if I’m laying vinyl sheet flooring or linoleum..is what I call it? I’m trying to help this lady out, shes on a low income so not much money at all. However, she needs new linoleum put in kitchen and dining rooms. But the kitchen flooring in messed up where some bright person scraped up old flooring and kind of gouged into the wood flooring. Any helpful ideas would be appreciated…I’m a woman and have no idea what to do about this problem. Thanks 😊
I agree that you do a lot better job than the majority of folks making articles on here. My only concern with this article is you laid down a moisture barrier and then punctured it with fasteners putting down the mdf. Not sure what the substrate looks like for moisture but this could cause you a problem long term.
Jesus spoke these words, lifted up His eyes to heaven, and said: “Father, the hour has come. Glorify Your Son, that Your Son also may glorify You, 2 as You have given Him authority over all flesh, that He should give eternal life to as many as You have given Him. 3 And this is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent. 4 I have glorified You on the earth. I have finished the work which You have given Me to do. 5 And now, O Father, glorify Me together with Yourself, with the glory which I had with You before the world was. John 17:1-5
You erased your love and threw it away like a paper towel, you broke his heart without heart and logic. But you didn’t know that I was the main problem. I was that poisonous snake You and I both failed. Mr. Michael You will suffer like me for the rest of your life. And you lay down Your head is crying on the mattress and you always dream. You and I judged him a lot. You will always be alone like me and one day the dream will come true and smile at our beards, both you and me. You can’t get anywhere by deleting your Telegram. You and I can never find someone as pure and innocent as Roya. If you didn’t answer me, and you didn’t betray your love, I wouldn’t be here now, if it weren’t for these ridiculous games, you would have lived in complete peace with your love. bye😼😹😹😹😹👋
I empathize with the frustration of handing the next person a piece of junk covered with something pretty. Wasteful, dishonest and SAD! However, I find it incredibly satisfying to bring everything up to code, solid and done right!! That’s where your incredible articles come in. Can’t thank you enough!! 😊
I did this exact thing in my studio space above my detached 2-car garage. There was only 1/2″ subfloor over 24″-on-center joists (!!!). Needless to say, it was a bit springy. The extra 5/8″ made it feel rock solid, and it’s much quieter to walk on. Will be installing a vinyl plank floor over it soon, with help from Jeff’s articles 👍
Make SURE you know where your water lines go before doing this. Laminating the subfloor in this way was how I found out the fire suppression lines in my condo were mounted directly to the underside of the existing subfloor. That made for an exciting night – especially because no one in my condo knew how to turn off the fire supression system, so water poured into my condo for 3 hours before we found the right person. After spending a solid week repairing water damage in the floor below (just my garage, thankfully, and not a neighbor) I marked out the fire suppression system on the old subfloor, and made darn sure to stay 12″ away from the lines when putting in the new screws
Question: I was waiting for you to explain how you were going to address the vapor and insulation issue causing condensation between the subfloor and flooring but you never did. Did you put a vapor barrier and insulation under the mobile home or fix holes in the existing vapor barrier and insulation? I have the same problem but worse. The plastic belly wrap was missing, insulation hanging, and my floors were bleeding on the Summer between the vinyl tiles because of condensation coming through the plywood subfloor and getting trapped under the vinyl tiles.
Subfloor is being removed from my home, unfortunately it had to be done. Urine stained and water warped MDF boards had to go. It’s like 70% done then we have to address a couple spots where the original subfloor is water damaged and rotted. Just the smell of that subfloor as it was pulled up reassured me that we made the correct call.
Plywood is crappy these days and often pretty bowed. I was taught to run a row of fasteners straight down the middle each direction forming a cross. Next, working from the center outwards, nail each quadrant. This forces the bow down and outward. You didn’t, but I can’t count the times I’ve seen people place the sheets, then nail all the seams first. 🫣 I’ve installed flooring since the mid seventies, learning from my grandfather. It’s refreshing to watch your articles explaining the why’s and how’s to those that watch. Some new to the trades, but I’ll bet many are diyers.
Future cable contractor likely won’t use the old cable, and won’t take time to remove and use existing holes, likely just drill into living room/office and run new cable to whatever rooms they want (or just to router for wifi nowadays). Up to you to seal all the holes nowadays, not like decades ago when they used grommets.
In the beginning of the article where the floor at the by the wall wasn’t level and you could put your finger under the ruler how did you raise up that end of the wall I just saw you put a piece of plywood down about 8 inches off the wall but you didn’t show how you leveled it off when it dips down on the sub floor
Starting at 8:30, those lousy cable wires belong behind sheetrock. I would use a drill and jig saw to cut out a piece of the original subfloor (if it’s not accessible from a crawlspace), and wire the lines though the walls by using a sheetrock knife or roto-tool to cut a line even one foot above the floor, along the wall, to where they want it coming out. It would delay the project by a day, but the alternative, of having to live with that crap forever, sticking out of the ground, always makes it worth it.🙂
much respect sir, been a floor guy for 37 yrs…saved up and bought a couple rentals for retirement and been perusal you for a few yrs now…also been doing part-time mobilhome work and it’s crazy what you have to figure out how they did things…hahaha…hope you enjoy your time here, you’re one of the good guy’s…how do you say it…cheers friend.
I have a question im remodeling a Mobile home 1st question. Can you remove the windows and replace with “Real ones? 2nd. Can you cut out a wall frame it to add a Door? 3rd do you have any articles showing a Bathroom remodel where you remove a Big garden tub to build a Large walk-in shower? I’m wanting to learn how to move the drains add a second shower head, with the faucets that come from the wall not the actual surround system? Know it’s ALOT of questions I’d appreciate any one answered. Thank you for your post. You’ve help me have to courage 🧘🏾♀️ to Try my own Home updates. New Females Power tool gal 😏👍🏾
I wish you could come and do my house lol. My house was a flip a few years ago before I bought it so the flooring isn’t that old and I have soft spots in different areas. Unfortunately I learned after I bought it that the flippers didn’t do a good job at all, they just covered things up. Anyway even though i’m not handy person I love perusal your articles. I learn a lot!
From a building science perspective, the code mandated crawl space ventilation attempts to defy reality. Hot warm moisture saturated air enters the cool crawl space and condenses. If a vent fan is installed to pull outside air in to the crawl space, the bottom of the floor will collect rain drop(s and rain down on the bare ground. The informed recommendation is often to install extremely heavy plastic sheeting with the sheets over lapped and vapor sealed to each other and the perimeter. To prevent rodent problems they recommend, 4 inch deep pea gravel both above and below the plastic sheeting. Supposedly it is impossible for them to dig because it rolls into its self. Then seal the crawl space and most important install an economical to operate whole house dehumidifier that pumps the moisture into a drain exiting the house. An informative experiment is to fill a glass or metal cup with ice and then add water. If you take it outside and set it on a hard surface, a puddle of water will collect around it. Often it can be shocking to see how much water the air holds. Matt Risinger is a big proponent of whole house dehumidifiers.
Except that rotten floor is going to deteriorate and come loose and put to much weight on the insulation and it wont be long before your insulation is laying on the ground and you have a mess with even more stuff to REPAIR. Repair does not mean COVER, HIDE, TRICKS, or BUDGET. Do it the right way the first time!
You can check a carpenter square by using a known straight like on a sheet of plywood and marking a line, then flip the square over and mark another line as close as you can to the first one, if it’s a little off you can take a center punch and hit either the inside or outside corner depending on which way it’s off. 😉
Thank you! I’m on a budget. An old blind lady with sad strength. I’ve been replacing rotten wood under my fridge for months. Every step takes me forever. The rest of the floor does have weak spots. My joists are 24″ on center. I just want the floor to last as long as me. Putting plywood on top seemed ok to me but I’ve been getting advice against it. Now I’m feeling more comfortable. Again, thank you very much!
I couldn’t help but chuckle – the finishing in my basement was paneling over paneling, because the paneling underneath was wet and rotten. It was so bad that I could poke my finger through it, but they “fixed” it by just putting another layer over it. Really expensive and difficult to repair, but buyer beware I suppose. 🙁
Wish I woulda seen this a month ago…had the exact same situation, and I had an idea to do use this method, but I couldn’t find any online resources on people who tried it! Ended up cutting out and replacing most of the subfloor. Joists all over the place, never on 16″ center. Took so much time and many instances of screwing into nothing. Well, now I know. Thanks!
Perfect timing! My mobile home flooring is swollen from various leaks and laminate floor was layed on top. Joints are popping. This is a 1975 single wide in Arizona 55+ park. I bought it right, but must be realistic. Surrounded by newer homes. I was just about to tear out bathroom subfloor. Plumbing is all replaced and roof is fixed, so cautiously optomistic. A little concerned about covering the soggy stuff, but think it should dry out with this 115 heat. Your thoughts?
This article seems contradictory concerning the various conditions of different parts of the floor. Now some schmuck (like a previous owner of my mobile home) may decide that they don’t want to take the time or expense to replace a subfloor that really should be replaced. While replacing the insulation under my house last summer, I noticed that the particle board under the bathroom was flaking off badly in several places. This is in addition to the joists presenting with horrid decay. So, I dig into my bathroom floor this year feeling more like a archeologist than a DIYer. The last owner put down some 7/16″ plywood and stick-on tiles. Under that was 1″ particle board with stick-on tiles. Under that was the original 3/4″ particle board subfloor that someone pulled off the linoleum to put stick-on tiles down. With the removal of each layer, I was hit with the sight and smell of wet wood and the particle board just fell to pieces with a light tap of the hammer. My thoughts suggested that if the Good Carpenter himself saw this, He may take His own name in vain. What a mess! Please be more direct about when it is ok to cover up old floor with good floor and when you need to be smart and just tear it out with a fresh start. I’ll be replacing this floor with 23/32″ ply topped with T&G OSB with a final layer of 1/5″ luan for the linoleum. All this of course after I replace several joists and bottom wall plates. I am on a very tight budget (SS) so this is a BIG expense for me. Being disabled is a major set-back as well, but the local American Legion is sending help.
I purchased a manufactured home and I had to pull all the flooring up. I though the subfloor was soft, but found that there was way too much padding under the vinyl floor which was making it feel like I was walking on a mattress. The 3/4in particleboard is solid with no soft spots. Whoever put the flooring in decided to use self leveler on the particleboard and it is not level. I was told the best fix is to put 3/8in plywood over the particleboard and just staple it with no regard for where the joists are and where the “self leveler” is. It looks like you would recommend that I use screws and screw it to the joist?
I read elsewhere and was informed by a guy in the flooring dept at Lowe’s not to attach the upper layer of plywood to the joists? Only the original subfloor should be on the joists. The upper layer is just attached to the subfloor with 1 and 1/4 screws (can use construction or sheetrock screws)? I have 3/4 sub floor and 3/8 plywood on top of that? Will that work?
Jeff I have to ask as I have been perusal your articles and listening to you, wouldn’t it be very expensive on adding the plywood over the top of what already there, especially like in my case in the bathroom the toilet sinks when you sit on it, which means I need to tear it all up and probably have to put in 2×4 or 2×6
Ok question at 1:47 you show how from the 4 foot line to the wall has a nice gap. When filling in how do you aim to remedy the gap? I am just about to start work on a 1985 Single Wide in Indiana. My floors have 2 soft spots one in the hall and another in the closet of a bedroom. I am getting quotes currently for the roof to stop leaks they mentioned I may need more bricks.
I knew when I moved into this old house the remodel before i bought it was maybe a cover up in some places. The first obvious on was the back part of the house, see a crack come across the ceiling as I was putting more things in that room up stairs. So with in a month or so of moving in I decided to check this out as much as i could without opening any thing up. What I realized was that the second floor on that part had only three cross beams besides the outer frame. Leaving two spans of 4 feet, and one at about 3 and the other around 2.5 feet. So I built a support frame from about 1/2 of the room on the first floor to add support for that center beam, where that crack in the ceiling showed up. Well now about 12 year later I have dips in my first floor at those 4 foot spans, and the one side is concerning. I don’t want to take up the whole floor, for the huge reason is the cost and that fact there is a large kitchen counter and sink on the one side and it covers those spans very well, so I don’t want to move it all out. the floor feel like they might have even used Masonite and not plywood or the plywood is rotting or just weak from the long span and a kitchen table one it for many years. This part of the house is basically built on the ground and I have no way under it all. There is a small opening on the one larger better 4 foot area, at my outside basement entrance and I put my cell phone on a stick and slid it under and as best I can tell that area is not rotted. So I can guess it was just to much weight at 4 foot span.
I understand about the budget, but how much would cost to shop vacuum up all the stuff between the layers. Also the expense in the adhesives between the layers is not cost prohibitive in the long run. For all the time it takes, add some more screws. Once the flooring and baseboards are done then you find a squeak. Then you slap your forehead with the palm of your hand.
I thought i would have to do the same in the house we just bought. Two first floor rooms had floors that creaked with each footstep. I was very close to overlaying new sheet wood, but decided instead to put roof felt over the construction insulation under the existing floating chipboard floor, and then another layer between the chip and the insulation that had been used to raise the floor level. After relaying the laminate floor it is silent. But handling that sheet flooring is harder work than you make it look!
“Somebody made an economic decision…” Yes, and I bought that house (regular house, not a trailer home) and now have to move ALL of my stuff back out so I can fix all of the floors. The seller (and the realtor) did me dirty. I was an out-of-state buyer and couldn’t walk the floors before the purchase. It seems that no one else (realtor, inspector, appraiser) did either. I am now paying the price. I really appreciate this website because I have a ton of work to do.
When you cut the plywood in half on the plywood you installed in the doorway,i thought you cut in half so you could slide the new plywood under the door jambs. Seeing this isnt what you did. How do you finish the flooring around the bottom of doorjambs without having a gap? Wouldn’t it been better to have cut the bottom of the door jambs enough to fit the plywood plus whatever the finished flooring is ? Wouldn’t this way have a better finished look? Thanks 😊
im 99% sure the previous owner did the same ‘patch the bad spot put a new floor on top’ strategy in our house, which is why i clicked on this article in the first place. i know next year im gonna need to start budgeting to fix it. weve only been here a year and a half and are starting to fall into soft spots, to the point where i toss random scraps of plywood over top of them and a thin rug over that, just to tide us over lol. this article is super helpful to give me an idea what im going to be getting into when i start this project, thanks for making it!
Probably the stupidest question ever—roast me; I’m ready for it! So remember in the beginning when you the floor was so uneven you can stick a finger under it? Is it still uneven? I understand you laid new plywood…but wouldn’t new even plywood on uneven floor just make a new plywood uneven floor? I’m so confused! 😔
You have to really watch these contractors these days. They are money hungry and if you dont know what to look for they will hide and get over on customers. Its no code of ethics in the contracting world these days. I recommend only using license contractors who are bonded and insured. Make sure you verify their licenses and paperwork before paying and signing any contracts.
I find more squeaks as time goes on. I presently have a wood floor that has sheet vinyl between it & the subfloor. I’m NOT impressed. Going to have to remove the vinyl so I can see where the joists are. I suspect the subfloors were all secured with nails. I already know the walls were done with nails.