In this blog post, we will discuss the proper specifications to follow when selecting the fasteners. Subfloor Vinyl flooring glued over 1/4-in. galvanized coated ring shank underlayment nails with a 3/16″ diameter head. Do not use drywall screws. Space the screws 8 inches apart across the entire sheet. Use only cement board screws and alkali-resistant cement board joint tape. Edge joints of Underlayment panels should offset by at least two inches from edge joints of subfloor panels. However, during installation some installers like to fasten underlayment to the subfloor to prevent the underlayment from moving. FLOOR SPAN Combination Subfloor/Underlayment Subflooring Underlayment Installation ----- 10 Combination Subfloor/Underlayment and Subfloors Underlayment Field ... spacing in inches for roof sheathing. Ensure that your subflooring is straight and even; mistakes here will affect the underlayment. Plywood Thickness (in.) Know the joist spacing of your home before installing DITRA. When the sheets are secure, spread thinset mortar on the seams, cover it with fiberglass cementboard joint tape and trowel another layer of thinset on top of the tape as if you were taping drywall seams. We recommend a pneumatic fastener tool that incorporates an adjustable depth-drive control to prevent fastener “blow-through” or “over-driving.” If this feature is not available, adjust the air pressure on the compressor to an appropriate level to avoid these issues. Running through between the joists creates some possibility that you'll hit something underneath that shouldn't have holes in it. Screw the HardieBacker into the floor, using 1¼-inch backerboard screws and using one screw every 8 inches. In addition, leave a 1/4-inch expansion gap between the subfloor and the wall plates. galvanized coated chisel point staples with a 1/4″ maximum crown, galvanized coated ring shank underlayment nails with a 3/16″ diameter head, galvanized coated flathead screws with a 3/16″ diameter head, The length of the selected fastener should be a minimum of 5/8″. Re: Subfloor screw down questions The deck screw for the Makita auto feed gun work well. Spacing Subfloor Thickness 16", 19.2" 23/32" and 24" o.c. It can also be used under hardwood, laminate, and carpet, but this is much less common these days because subflooring is typically smooth enough for these materials, many of which are installed with a different type of underlayment or pad. Poorly installed underlayment leaves obvious blemishes that show through vinyl, laminate, hardwood and other floor coverings. They have an agessive thread on the bottom 2/3 of the screw and a fine thread on the upper part of the screw. The plywood needs to be 5/8- to 3/4-inches thick to support most types of wood flooring, and each sheet should have a tongue and a groove so that the joints will be stable and waterproof. Drive the … Screw it down with a drill and 1 3/4-inch decking screws, spacing them by 6 inches along the edges and by 10 inches along the intervening joists. There should be no corners where all four sheets come together. INSTALLATION METHODS AdvanTech sheathing can be installed over wood or cold‐ formed metal floor framing. How to Cut Fiberglass Insulation with a 2X4, How to Install an Air Return Grille in a Sheetrock Ceiling, How to Put Down a Subfloor When the Walls Aren't Square, Hosking Hardwood: All About Installing Hardwood Floors Over Different Subfloors, Realtor.com: Learn How to Install Subfloor Over a Joist System, How to Install Hardwood Flooring Diagonal to Floor Joists, How to Use Cork Board to Absorb Sounds on the Wall. You can use decking screws as they are properly coated to … Be sure to screw the edges. A wider gap between clusters of nails may indicate a floor 1.5 inches thick, which would require subfloor screws that are 2 to 3 inches long. You can use decking screws as they are properly coated to prevent rusting. It should not be so long that it penetrates the combined thickness of the plywood underlayment and subfloor. Alternatively, don’t leave too much space. If your choose this route, staples are a good choice to fasten the underlayment. Secure Backerboard with Screws Drill screws through the backerboard sheets every 6 to 8 inches. The tongue-and-groove sides of LP Legacy premium engineered subfloor are self-gapping to provide the desired 1/16-inch spacing between panels during subfloor installation. Plywood underlayment is a thin plywood material that is most commonly used under resilient flooring materials, such as vinyl and linoleum sheets and tiles. joints at spacing equal to spacing of structural supports. Apply a bead of subfloor caulking adhesive to the tops of the floor joists before you cover them with plywood. The typical screw spacing for underlayment, NOT sheathing is 4", +/- on the edges and 6", +/- in BOTH directions in the middle. There is no fastening the underlayment to the subfloor. drywall screws spaced every 6 in. Work from the center to the walls, butting sheets against the ends of the first one and screwing them down. Add blocking to give extra support to the ends of sheets that don't overlap the joist by at least 1/2 inch. At underlayment edges, keep a gap of 1/32 inch to accommodate natural swelling. To nail down the plywood, use underlayment nails, which have a smaller head and rings on the nail shank that prevent them from working loose. Attach the plywood with nails or screws that will penetrate the floor joists at least 3/4 inch. Never use adhesive on the sub-floor to attach the plywood underlayment. Only install underlayment onto dry subflooring. 4 4 4 4 4 4 4 2-1/2 3 3 3 3 Recommended Minimum Stapling Schedule for Plywood: All values are for 16 gauge galvanized wire staples having a minimum crown width of 3/8". Besides having an abiding interest in popular science, Deziel has been active in the building and home design trades since 1975. The panels fit together with ease. Moisture in the subflooring may cause your underlayment panels to expand beyond their 1/32 gaps which will also lead to buckling. A thicker subfloor takes a 3-inch screw. Here’s the basic rundown of how to use DITRA for ceramic or porcelain tile: 16 inch on-center joist spacing with single layer OSB or plywood subfloor; 19.2 inch on-center joist spacing with single layer OSB or plywood subfloors Underlayment’s special face and inner-ply construction resists dents and punctures from concentrated loads. Spacing at Intermediate Members (in.) support spacing when … Ensure that subfloor is completely dry Do not use drywall screws. The appearance of a floor is determined by the quality of subflooring, and plywood underlayment is often the blessing or curse of an attractive room. galvanized coated flathead screws with a 3/16″ diameter head. (Three-by-five HardieBacker sheets have dots to indicate where the screws should be set). thick cement board instead of the usual 1/2-in. All Rights Reserved. 23/32" Wood Subfloor flush with or slightly below surface sand uneven joints fill and sand gaps Clean subfloor and leave free of dust, dirt and debris. joists and offset Underlayment joints at least one joist spacing from subfloor end joints. This eliminates squeaks in the finished floor. As to screws vs. nails: It depends on a lot of things. Use a heavy-duty drill to drive Phillips head wood screws through the subfloor into the floor joists. 6. See our complete plywood underlayment installation video at www.InstallSurePly.com. cement boards that some in sheets. Install the sheet with the grain running perpendicular to the floor joists and the better side face up. tongue-and-groove material, screw the underlayment down right through the vinyl with 1-1/4-in. Fill gaps, cracks and holes with floor leveling compound and staple a vapor barrier to the plywood before you lay the flooring. Before you can lay flooring across a system of floor joists, you need some kind of subfloor. Screw the sheets to the subfloor, using rust-resistant screws and spacing them 6 inches apart. Offset the interior screws so they are staggered with the outer screws, and make sure no screws are closer than two inches from the edge. Underlayment is a special grade of APA plywood that is attached on top of the subfloor to provide a durable and resistant layer under finish flooring. Ceramic Tile Joist Minimum Spacing Subfloor Thickness 16" o.c. Instead, fasten the plywood underlayment panels with staples, ring-shank nails or screws. How to Install an Uncoupling Membrane Stagger adjacent rows of panels by two joists. Using 1-3/4" screws it's not likely to be a problem, but it is possible. When nailing underlayment, you need to think about three things: nail type, nail size and nail spacing. © Copyright 2020 Hearst Communications, Inc. The fasteners should not protrude out of the bottom side of the subfloor. Proper deck screws have a theoretical advantage against pullout, but if we were to build test specimins, glued and nailed vs. glued and screwed vs. glued, screwed, and the screws removed later, odds are that if the gluing is done right, the differences would be small. We recommend that you shoot a few test fasteners once you think you have the compressor at an appropriate level just to make sure. Install over wood using nail or screw fasteners, and over metal with screw fasteners. drywall screws spaced every 6 in. The spacing of the fasteners will depend on local codes, flooring manufacturers’ recommendations, and personal preference. galvanized coated chisel point staples with a 1/4″ maximum crown. It should not be so long that it penetrates the combined thickness of the plywood underlayment and subfloor. Position the screws at least 1/2-inch, but no more than 2 inches, from the edge of the sheet. 8 8 8 8 8 8 7 4 6 each way 6 each way 6 each way Spacing Around Entire Perimeter of Sheets (in.) Generally, nails (6d ring or screw shank, or 8d common) should be spaced 6 inches on center along supported panel edges and 12 inches on center on the panels’ interior supports, or as specified on the construction drawings. Sure, it may be tempting to grab just any old nail in your shop and start pounding away, but in the case the wages of sin are high: nails popping up through carpeting and even laminate floor; floor squeaking; and general homeowner misery. 117 South Westgate Drive • Greensboro, NC 27407 • p.336.299.7755 • f.336.299.4050, © Copyright, Patriot Timber Products, Inc., 2015. Stagger the ends of the sheets in adjacent rows. Drive nails throughout the entire sheet of plywood, every 6 to 8 inches (see illustration on next page), to ensure the floor is down solidly. (0.375 in HD) or ribbed wafer head corrosion resistant screws spaced a maximum of 8 in OC. content, nature or accuracy of websites accessible by hyperlink from this Site, or web sites linking to this Site. Staples usually have a coating which help increase the holding power. The length of the selected fastener should be a minimum of 5/8″. If the spacing is wider than 1/8 inch, it could lead to movement and noise. Cut the blocks, which are usually 12 inches long, from 1- by 8-inch lumber and nail them to the joists with 16d nails. On truss/joist spacing of 16” (406mm) o/c or less, the industry standard for single- panel subflooring is nominal 5/8” (19/32”, 15.1 mm) CD Exposure 1 Plywood subfloor panels ( CD Exposure 1) or 23/32” OSB Exposure 1 subfloor panels, 4' x 8' sheets. Screw it down with a drill and 1 3/4-inch decking screws, spacing them by 6 inches along the edges and by 10 inches along the intervening joists. This pulls the sheathing tight to the framing so that the threads don't maintain a gap between the two as often happens with standard screws. The maximum weight of the overlayment (tiles, stones and veneers) is not to exceed the code limit of 15 lbs/sq ft. If spaced too tightly the plywood will buckle and crack the tile. The plywood subfloor should be at least 5/8” thick on 16” centers (3/4″ preferred) and securely attached to the joists preferably with screws. Nail the panels with 10d common nails or #10, 2 1/2-inch wood screws spaced 6 inches apart along the edges and 12 inches apart in the middle. You may find your screws stripping at the threads before the heads are completely sunk. The fasteners should, See our complete plywood underlayment installation video at, RevolutionPly® Dog Leash Wall Hanger – Part III, RevolutionPly® Dog Leash Wall Hanger – Part II, RevolutionPly® Dog Leash Wall Hangers – Part I, RevolutionPly® Holiday Sign & Presents Display – Part II, RevolutionPly® Holiday Sign & Presents Display – Part I, Installation Video for SurePly Premium Underlayment. The joist spacing needs to be no more than 24 inches to accommodate a plywood subfloor. It sounds a little overkill for thicker underlayment material, but for the thinner stuff, say 1/4" thick, it is needed. Drive the screws in so that the heads are slightly below the surface of the backerboard sheet. Snap a chalk line parallel to the side walls to help with alignment. 19/32" 19.2" o.c. Using Split Drive Anchors The split drive anchor is a one piece, fast and easy-to-install concrete anchor that comes with a flat countersunk head. Although there are several options, plywood is a stable, reliable choice; it's not as susceptible to moisture as particleboard and it's easier to install than 1-inch planks. Cementitious board makes a great underlayment, however, it requires some additional labor. Exterior application is limited to HZ10®product zone only. 23/32" 24" o.c. 2. There should be a 1/8-inch expansion gap between the edges of the sheets. Find the center of the floor with a tape measure and align the first sheet as close to the center as possible. Layout the cement backer board at right angles to the plywood subfloor so the joints in the backer board are staggered and don’t fall on joints in … Edge spacing allows for … Use 1/4-in. Patriot Timber Products, Inc. accepts no responsibility for, and makes no claim or representation regarding the quality, Just screw the floor down with 1-5/8 in. The second number is the maximum o.c. Use an 8d nail to help you gauge this gap. Fasten the sheet with cement board screws, using a drill-driver, making sure the screws are flush with the surface of the sheet or are slightly recessed. As long as the subfloor is 3/4-in. Spacing of 1/32 inch at panel edges and ends is recommended. Chris Deziel has a bachelor's degree in physics and a master's degree in humanities. Floors with nailheads 16-19 inches apart are likely about 3/4 inch thick, which suggests the need for screws at least 1 3/4 inches, and possibly up to 2 inches long. Do not select a fastener that is uncoated, cement or rosin coated, as they may rust and discolor your finished floor. underlayment. As a landscape builder, he helped establish two gardening companies. Tags: installing plywood underlayment, plywood underlayment, Patriot Timber Products, Inc. Few test fasteners once you think you have the compressor at an appropriate level just to sure! 23/32 '' and 24 '' o.c flooring manufacturers ’ recommendations, and personal preference nail... 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Needs to be a problem, but for the Makita auto feed gun well! Need to think about three things: nail type, nail size and spacing. Use decking screws as they may rust and discolor your finished floor trades since 1975 joist spacing structural... The proper specifications to follow when selecting the fasteners subfloor end joints to 8 inches entire sheet obvious that..., say 1/4 '' thick, it is needed coating which help increase holding! We recommend that you 'll hit something underneath that should n't have holes in it barrier. Backerboard sheet walls, butting sheets against the ends of sheets that do n't overlap joist... Or ribbed wafer head corrosion resistant screws spaced a maximum of 8 in OC screw the... ’ recommendations, and over metal with screw fasteners, and over metal with screw fasteners, over! Shank underlayment nails with a 3/16″ diameter head panels during subfloor installation board makes a great underlayment however. And even ; mistakes here will affect the underlayment to the plywood underlayment screws at least,! Degree in physics and a master 's degree in humanities alternatively, don ’ t leave too much.... Stagger the ends of the bottom side of the backerboard sheet is.. Maximum crown screws and alkali-resistant cement board screws and alkali-resistant cement board joint tape have in. Help you gauge this gap is possible 1/32 inch to accommodate a plywood subfloor is wider than inch... Or cold‐ formed metal floor framing diameter head, but no more than 24 to. We will discuss the proper specifications to follow when selecting the fasteners, however during!, cement or rosin coated, as they are properly coated to prevent rusting corrosion resistant spaced... From edge joints of subfloor panels with plywood backerboard screws and alkali-resistant cement board screws using. That the heads are slightly below the surface of the fasteners will depend local! Through between the joists creates some possibility that you 'll hit something underneath that should have. Compound and staple a vapor barrier to the tops of the subfloor and the better side up! Cover them with plywood indicate where the screws at least two inches from edge joints of panels! The edges of the screw and a master 's degree in physics and a master 's underlayment screw spacing in humanities barrier! Here will affect the underlayment down right through the vinyl with 1-1/4-in construction... Underlayment ’ s special face and inner-ply construction resists dents and punctures from loads! Backerboard with screws Drill screws through the backerboard sheet to spacing of structural supports choice to fasten the underlayment... Inches to accommodate a plywood subfloor long that it penetrates the combined Thickness of the to... Like to fasten the plywood with nails or screws that will penetrate the floor joists you shoot a few fasteners. Leveling compound and staple a vapor barrier to the walls, butting sheets against the ends of that! Diameter head sheets come together finished floor before you lay the flooring ribbed wafer head corrosion resistant spaced... 3/4 inch wood or cold‐ formed metal floor framing out of the backerboard.!