Remember, plywood only has a tongue and groove on the sides, not on the edges, since these will be nailed into the joist. For hardwood floors, use some felt layer over the plywood underlayment for better results. This will make installing surface flooring a much simpler task. To install a floated subfloor system, first place a layer of plywood subfloor panels with the edges parallel to the wall. It’d be kinda messy. This is particularly important if your old sub floor has lumps and bumps in it. Cupping occurs when hardwood floorboards begin to curl along the length of the board, somewhat like a taco shell but less pronounced. There are also other trades between. Step 9: At this point, the plywood subfloor is complete. Sheets of 3/4" plywood weigh as much as 90 pounds!!! Make sure no one is standing below so the pieces can fall freely to the ground. (See our wood joist comparison.). The spacing of the joists supporting the floor determines the plywood thickness. Step 3: Lift up the plywood and put construction adhesive across the joists. Because this floor may be exposed to weather before the second floor and roof can be installed, we covered it with Zinsser Shellac. When you build, you always stagger. Chalk lines are pulled all the way across all the joist tops at the 4 foot marks so we can check our accuracy with each sheet of plywood being attached to the joists. Stagger adjacent sheets so that they do not start on the same joist. The cost to do this throughout the 1,200 sf home was about $1,000 for materials and labor. There are unique challenges in every plywood subfloor installation, including important building codes specific to your area that no single article could completely address. Always install plywood or OSB long-ways across the joists. For best results, you’ll move back and forth across the whole sheet to ensure a tight fit. Assuming a remodel, this is going to involve bringing the plywood to the location by hand, as opposed to assistance by a crane. Learn how your comment data is processed. The chalk lines serve as guides. Although OSB (orient strand board) is sometimes used, the most commonly used type of wood is C-D grade tongue and groove plywood. Install one sheet of plywood at a time. More plywood sheets are nailed down, staggering seams for a stronger fit. Article quote from - Position of Underlayment to Prevent Cracked Tile … At times it may be necessary to go shorter on this measurement, but when this happens, the plywood will need to be cut to accommodate the shorter length. If the house is out of square, it will make it exceedingly difficult to get the plywood straight on the joists. In my mind, there's even a waiter with a tray full of drinks with little umbrellas. you are such an inspiration .. just amazing. We shared the day with a dozen volunteers, working primarily on structural components of the house, including installing floor joists, installing a 3/4 inch plywood […] The wood i-joists are more forgiving than traditional joists because they have a wider nailing flange. My rooftop sun deck fantasy would not come true on this day. At 16″ on center, there will be 7 joists under each piece of plywood, and each piece will end in the middle of the next joist. I'm hoping that if I install some 2x4's underneath the subfloor perpendicular to the joists the subfloor will be reinforced enough. How to install plywood to a subfloor around a toilet. Installing wood subfloors over concrete how to install a plywood subfloor one installing wood subfloors over concrete how to install a subfloor on joists how to install subfloor panels 9 common subfloor mistakes and how to. Nails need to be 8d, spaced every 4" and staggered. First, renail the existing plywood subfloor, so that the old nails are tight, and add new nails to achieve a maximum nail spacing of 6 inches. To install a floated subfloor system, first place a layer of plywood subfloor panels with the edges parallel to the wall. These chalk lines run the entire depth of the Momplex, perpendicular across each floor joist, every four feet. You do it on the top of the joists and then you put the subfloor down on the joists and glue it and nail it and screw it and that glue will bond it down, construction adhesive. In this installation, we used Portable Cable’s Round Head framing nailer. Where floor joists are spaced 16 inches on-center, whether or not a 3/4-inch plywood subfloor is adequate for this type of installation is a judgment call. Stagger stagger. Since 2009. We are big supporters of Habitat’s mission, to provide safe, dry, and affordable housing to needy individuals and families. Stagger the joints so no joint runs into another joint. Then I traced a line to the mark I had made on the previous sheet of plywood, making it easy to find the joist and nail the plywood to it. Use a ¾” spacer between the plywood and the wall and a 1/8” spacer between panels. Step 8: Trim the edge of the floor by snapping a chalk line and cutting with a circular saw. The subfloor is typically made from plywood or oriented strand board (OSB). The tongue and groove are only along the 8 foot edges. ⚛ The information about How To Install Plywood Subfloor Over Joists Easy Steps For Installation is completely presented here. Prepping for a subfloor installation happens long before you are actually laying the plywood. Install Subfloor Over Joist Flooring; How To Install Subfloor On Joists Reinforcement Learning; Install Subfloor Over Joist Flooring. Tom: Yeah. Lay the panels out flat to cover the subflooring. Make certain the end of the plywood panel is positioned at the middle of floor joist and secure the panel in place using decking screws approximately 12 inches apart and within 3 inches of the edge at each joist. Dry fit components first to make sure sheets land on the center of joists. Errors tend to compound as you work through these steps. Since it has tongue and groove the joints which end between the joists do not need extra reinforcement thus less work. New sheets are carefully pounded in place with a block protecting the open groove side of the plywood. We put the upstairs floor joists up, and I thought the very next day I'd be getting a sun tan on a roof top deck. Side-to-side spacing between our joists is 18 inches on center at its greatest. For example, if you install resilient tiles or sheet flooring over a subfloor, any bumps, dips, or voids in the subfloor may be evident in the finished flooring. We dry-fitted the plywood over the shims to make sure the new subfloor was even with the rest of the flooring. We are using ring shank nails, or nails with rings on their shanks. Not so much the case ... we built stairs, backfilled, insulated ... just to name a few projects that had to get done as I tried not to glance up at those open floor joists ... and finally it's plywood day. Each subsequent piece of plywood will depend on the first piece being installed correctly. Step 7: If everything looks good, use a pneumatic framing nailer to fasten the boards to the joists. We consulted the manufacturer of our floor joists for nailing recommendations. Loose or damaged subfloors can cause squeaking and affect the performance of the finished flooring that is installed over it. Dry fit components first to make sure sheets land on the center of joists. You can see on the non tongue and groove side of the plywood, joints are made in the center of the joists. If you are thinking of laminate, use a pad to cover the underlayment. Later this week we will be showing wood I-joist installation, both with a rim joist, and without, in a situation where a rim joist cannot be installed due to the position of the wall next to an adjacent house. And the plywood is layed on top of the joist. You’ll be hammer on the tongue edge of the board. Step 6: Check that the sheet of plywood is square and tight against both sides. After each sheet of plywood is layed down, I went and marked the open edge, with a mark centered on the open floor joist. Use a chalk line to mark the panels for cutting, and wear a dust mask when cutting the plywood. Matching up with the chalk line, reaching the center of the joist. Step 2: Measure and dry-set the first piece. https://vinawoodltd.com/wp-content/uploads/2020/09/logovinawoodsmall1-1.png, https://vinawoodltd.com/wp-content/uploads/2020/11/trim-edge-of-plywood-subfloor.jpg, Copyright © 2020 VINAWOOD Co., LTD. Headquarter: 92 Thien Duc, Yen Vien, Gia Lam, Hanoi, Vietnam | Hotline: +84-83-333-2333 | Email: Email: plywood@vinawoodltd.com |, Consider both load bearing capacity and deflective properties when selecting subfloor materials. And it should be ready for the next flooring installment. Then, using a hammer and nail to tap in two set nails, one at each corner. Take our word for it: this is important and very hard to correct if done improperly. This is best achieved using a sledge hammer and a tapping block. Cut them to lengths so that you can alternate the ends throughout the room. How to Install a Subfloor on Joists Submitted by Ana White on Thu, 10/13/2011 - 00:50 We put the upstairs floor joists up, and I thought the very next day I'd be getting a sun tan on a roof top deck. Every once in a while, I have been sneaking up to sit on the floor joist, just dreaming of this day! Somewhere I saw something about leaving 1/8" gap. Another approach would be to completely cover the project with large tarps in between efforts. In this article, we’ll cover the installation of a 3/4″ plywood subfloor, including tips and pictures from our work with Habitat. For subflooring, you use tongue and groove plywood. Make sure the plywood is square. Tip: plywood sheets are always installed with the grain across the joists. Next is the subfloor. Concrete slabs should be flat, use a leveling compound to fill any depression or voids. Make sure the house is as square as possible going up – square foundation, square walls, square joists with proper spacing. 3 Answers. We started first with a 1/2 sheet. It is installed directly on top of the joists and provides more overall stability as well as a certain amount of moisture protection. Subflooring glue is applied to the tops of the joists. I knew that overall, the finished product would be far more level and feel more solid. The contact detail associated with How To Install Plywood Subfloor Over Joists is also mentioned to make it easy for a user to contact the furniture seller. You can snap a chalk line across the joists to make nailing simpler. You should leave these nails about 3/4″ out of the plywood to make pulling them easy if everything isn’t right. It was getting pretty late when we finally finished up. If you did this without a block, it would destroy the groove and make fitting the next row of plywood very difficult. Re-secure any loose wood subfloor planks, OSB, or plywood subfloors to the floor joists using 2-1/2" deck screws. We did this by simply starting with a 1/2 sheet of plywood on the first row, followed by a full sheet of plywood on the next row. On the four foot edges, your seams will fall on joist tops, so no need for tongue and groove. How far apart should the joists be, both side-to-side and front-to-back? Ensure that the sheet is still in the correct position, then nail down all four corners. Oneprojectcloser – This past Saturday the crew here at One Project Closer spent the day with Habitat for Humanity Baltimore, rebuilding a house in the Sandtown area of Baltimore City, Maryland. Fasten your first layer plywood subfloor as you normally should. Your goal is to have the plywood end exactly half way across the joist, so that the new plywood can start on this spot. Habitat provides a great opportunity to learn construction techniques that apply to your own DIY projects, while at the same time helping others in need. It's what makes a pile of boards and materials into a solid structure. Step 1: Get the plywood to the right level of the house. Underlayment covers subfloor flaws … If you tighten the plywood down to the joists near the edge, it is much more difficult to install the sheet. And this is how we lay the subfloor on top of those floor joists ... On the tops of the floor joists, we measure and mark every 4 feet - this will be the plywood seams. We measured and marked where the joists were so we could nail into them. We shared the day with a dozen volunteers, working primarily on structural components of the house, including installing floor joists, installing a 3/4 inch plywood subfloor, adding fire stops to first and second floor walls, and adding additional plywood sheathing to the exterior of the house. But we are enjoying it now! The second (top) layer of plywood joints should not coincide with the joists and the second layer should not be fastened to the joists. How to Cut the Subfloor to Access the Floor Joists for Plumbing. So it is critical that the second sheet of plywood stagger those weaks spots to get maximum rigidity in the floor prior to tiling. Replacing Entire Subfloor With new 5/8″ Plywood. As with all major construction projects, you should consider consulting a professional before attempting a job like this on your own. The Wood. Installation over concrete with a calcium carbide reading of greater than 2.5 percent. Put a nail every 8-10 inches on the surface. Install one sheet of plywood at a time. You guessed it, we'll be back to the half sheet on the next row. The second (top) layer of plywood joints should not coincide with the joists and the second layer should not be fastened to the joists. I was so thankful our cousin Justin was here to pack plywood upstairs. Make sure that the foundation is square, that the first floor walls are square, and that the joists are square. Vertical installation can be achieved through careful installation of a rim joist, and if necessary, blocking between the joists themselves. Step 8 It has been torture waiting for plywood day! Remember, you only do this for the first row of plywood. Who knew?! It is important to make sure the shellac covers the edges. NOTE: This is Part 1 of a 2 part series. We put the floor joists in in this post. Tell me, does anyone else feel like they are getting stretched apart hauling a full sheet of anything? You likely won’t be able to push the plywood into place by hand. Be sure the joists are dry and free of dirt before applying. It is exceedingly important that the first whole line of plywood sheets be perfectly straight and square. Step 4 Repeat Steps 2 and 3 to install … Solid joists take longer to burn through, and will provide structural support longer. Oneprojectcloser – This past Saturday the crew here at One Project Closer spent the day with Habitat for Humanity Baltimore, rebuilding a house in the Sandtown area of Baltimore City, Maryland. That’s basically how to install plywood underlayment. Plywood and OSB span ratings assume installation across the grain of the joists. Did you leave any expansion gaps between the short ends of the plywood? Plywood and OSB span ratings assume installation across the grain of the joists. A 3/4 inch sheet of plywood weighs approximately 75 lbs. You will notice that there is maximum flexing at the areas between the floor joists where two sheets of plywood meet. However, they must be installed and held vertical to ensure they do not twist, which would substantially weaken them. The sledge hammer will easily mar the plywood subfloor making it difficult to fit the next sheet into place. Step 2: Measure and dry-set the first piece. Shellac helps temporarily prevent water penetration on the surface and sides of the plywood. When installing decking you should lay the pieces so the long dimension of the plywood extends across the joists and the short dimension runs up the joist length. Chipboard is faster to install as it has tongue and groove. Once you’ve installed a vapor retarder, install your subfloor. (I'll be blogging about all the other projects we've been up to as well in the next coming bit). All Rights Reserved. Step 5: Tap the subfloor into place. I just set my saw blade to the depth of the plywood and ran it down the edge, removing the tongue. The second floor of this house is built with 2 x 10 wood I-joists (joists that resemble steel I-beams and are 9.5 inches thick), 16″ on center and spanning 13.5 feet. Be careful! Rather than repairing small spots all over the house, I decided to lay down a new plywood subfloor throughout the home. Step 3: Lift up the plywood and put construction adhesive across the joists. Select the smooth side of the plywood to be facing up. Next, lay a second layer of plywood at a 45-degree angle to the … Uncategorised; how to install plywood over existing subfloor We used a DeWALT 10″ circular saw for the job. Here's wishing plywood was like 45" wide, or I was like three inches taller. If you want to install ceramic or stone tile on a floor, 3/4″ plywood over 16″ OC joists is recommended, even though the code may only demand 5/8″ OSB over 16 OC joists. It’s important to note that when installing the plywood sheets, do NOT nail within 10 inches of the side closest to the tongue UNTIL the adjacent sheet is hammered in. 7.1 - Check the plywood panels for chipped tongue-and-groove edges. Always install plywood or OSB long-ways across the joists. The floor of any building or structure is its base and one of the most important parts, so when preparing to lay a plywood subfloor there are several things to keep in mind. Dry-setting is important. Fasten your first layer plywood subfloor as you normally should. Spanning ratings for plywood and OSB are based on this assumption. Many manufacturers recommend applying a continuous ¼-inch-diameter glue bead to framing members and using a serpentine pattern for supports that are 3½ inches or wider. Never go longer unless you have rechecked the spanning distance on the plywood and joists you are installing, as this could create a weak spot in the floor. I build and share smart, stylish diy projects. Conclusion. Also, these nails come coated in a glue on the shank, further helping keep the nails nailed down. The view up there is amazing. The wood grain of the panels should be perpendicular to the floor joists. Step 4 Nail down the rest of the sheet, spacing nails about every 12 to 18 inches apart down the joist. The boards are laid lengthwise, perpendicular, over joists and joined together. Make sure the plywood is square. Make sure your contractors are careful through each stage. We prefer 2 inch subfloor nails with reverse threads and coated in glue. Don’t skip using the block. After patching the subfloor and restoring the underlayment as shown in the photos it was time to glue and nail down a second very thin underlayment 1 4 in to assure a perfectly smooth surface. This span rating for plywood defines how far apart joists can be. Then when we went to put the remaining piece in, everything keeps to the pattern, fitting just right, like a perfect puzzle, only the pieces are 48" x 96" and weigh 90 pounds. Not Elmer’s glue. Repair any broken planks. Install a layer of at least ½” or preferably 5/8” ply over the existing planks. The right glue is very important here, it's what keeps your floor from squeaking. Step 4: Set the plywood on the construction adhesive with the tongue oriented towards the groove of the adjacent sheet. Carhartts are the new fashion accessory! Also, donâ t forget to wear proper safety If you’ve positioned the plywood correctly, it should be sitting half-way over the joist, right next to the adjacent piece, as shown below. When we got to the stair openings, we kept to the pattern (pretending there is no stair opening) and nailed the subfloor down on the other side. Charlie: Okay. Tom: You could use that but I don’t think I would. Laying your first piece in the outside corner of the floor you want the long dimension of the plywood to lay across six joists with the final edge ending up in the center of the 6th joist. Steps to Install 3/4 Inch Plywood Subfloor Step 1: Get the plywood to the right level of the house. Liquid Nails for Subfloors is a common product for this job. Then I got in trouble for making bad marks .... We all chuckled later when we realized I had had some help! Charlie: On the subfloor? Walk over a unfinished plywood floor that has only a single layer of plywood. Not exactly a Melissa and Doug puzzle! Don’t stack too much plywood on the same set of joists and overload them.https://c530a180aaf435517e4010cd1acc3002.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html. Coming from past experiences of screwing down subfloors, this really felt like we were cheating. Remember not to nail towards the last 10″ of the tongue side until the next sheet is installed. It aids during installation if the joists are installed exactly 16 inches on center throughout the floor. Shellac is not a long term solution to prevent the plywood subfloor from delaminating under the elements; however, it does provide some additional weather protection in the short term, and is worth the relatively small time and money investment for a project like this where it could be several weeks before the floor is under roof. Be ready for the next sheet is installed this span rating for plywood and span. Opposite corner lengthwise down the sheet affect the performance of the finished flooring that is installed over it best using... On joists Reinforcement Learning ; install subfloor over joist flooring ; how to install plywood or OSB across... From past experiences of screwing down subfloors, this really felt like were. 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For this job can fall freely to the floor joists for Plumbing mask when cutting the plywood is needed.