While a subfloor is not necessary to add structural strength when you'll be laying finish flooring on top of a concrete slab (as in a basement remodel), subflooring over concrete offers two other advantages: Dampness control. Lay 6-mil polyethylene sheeting over the concrete to minimize moisture migration from the concrete up into the wood flooring. I'd attach with screws [for removal if something goes wrong]. Duraamen’s Param 5500 goes on thin, in a 3/8" to 1/2" thick application. Greatmats recommends Sports Plus Designer Foam tiles, which are 2x2 feet in size and ⅜ inch thick. You don't want the plywood resting on the concrete because it will rot. Run the polyethylene up the sides of the walls 3 to 4 inches, and secure to the walls with construction tape. Construct a subfloor with sheets of 3/4-inch pressure-treated plywood over the moisture barrier. Technically, cement board can be laid over a concrete slab as the base for a tile installation. Do I just put down > 2x4s on edge and shim as needed, then install plywood over this??? This you can insulate with standard R-19 fibreglass, moisture barrier up. Now I've cut up the concrete floor, had a plumber run pipes, re-filled with bagged concrete, and leveled the cutout with self leveling cement. You can use a bubble level for this part, a torpedo or a 12" level would work nicely. on center. Over time, a sink or refrigerator water leak can damage and even destroy flooring materials and the subfloor below it. The back portion of the house has a 60 year old 600 square foot slab with approximately 2' deep footers. Leave a small air space between the concrete and the plywood. Undecided about the best way to cover and warm up the concrete floor in your basement? A better solution is to prepare and resurface the concrete slab so that it can accept thin-set adhesive or a mortar base onto which to lay tile. The chalk line will serve as a guide for the first row when permanently installing the flooring. How to Install a False Floor Over a Basement Slab. Ceramic and porcelain tile are so frequently installed at or above grade level on a cement board underlayment or directly on plywood that it almost seems novel to install tile directly on concrete. Q. Most subfloors over concrete use exterior grade ¾” plywood or OSB (Oriented Strand Board). How to Lay a Floating Subfloor over Concrete Part 2 Written by Michelle Keefe on May 05, 2010. Repairing a damaged subfloor is serious business, but it doesn't have to be scary. I would go with 3/4 personally. Build a Plywood Subfloor. Installing Tile Directly on Concrete . Overlap the seams about 6 to 8 inches and seal the seams with waterproof construction tape. A subfloor warms finished floors by 6°F (3.2°C) and provides protection from moisture. Once you’ve installed a vapor retarder, install your subfloor. How to Install a Base for a Concrete … False floors, also known as floating floors, are not permanently attached to the floor or walls. Installing a subfloor is a DIY job you can achieve with the right know-how. And it's a great way to turn an old concrete floor into something nice! Structurally Sound. Alternatively, screw rows of treated 1x4s to the concrete 16 in. Here’s step-by-step guide to help you prep a concrete subfloor for luxury vinyl: Step 1: Test the moisture content of your concrete subfloor. A particleboard subfloor is not recommended for a concrete finished floor. Learn how to install a subfloor in this step by step guide from Bunnings. Air gap subfloor panels elevate and insulate your finished floor quickly and easily. Concrete floor video on how to install concrete over an existing wood subfloor. When it comes to solid wood, both strip and plank flooring are acceptable as long as they are in good condition. A decorative concrete flooring material can be installed over an existing concrete slab, a plywood subfloor or a 3/4-inch solid hardwood flooring. Tapcon screws work well for screwing into concrete. The experts show how to repair a water-damaged subfloor. Then install your subfloor over that once your floor is level. A.Doug Mossbrook, president of Eagle Mountain HVAC, responds: None. Dricore subfloor membrane panel 3 4 in x 2 ft oriented installing a floating subfloor extreme how to installing plywood flooring over concrete theplywood insul armor the ultimate subfloor 12 recommended how to install hardwood floors on wood subfloor. 2. I'm preparing to finish my garage, but the garage slab sits roughly 8" lower then the rest of the house. A concrete slab that is structurally sound but has widespread surface imperfections can be covered with special subfloor panels or tiles made to go over concrete. Insulating concrete garage floors begins with covering the entire floor with 6-mil polyethylene, which will serve as a vapor barrier. Before installing a thin concrete or gypcrete floor over a plywood subfloor, what kind of membrane should be installed over the plywood? But, if your home has a plywood or board subfloor, it’s important to check out the type and thickness of the material you intend to use to determine what your limitations are. treated plywood to the concrete with concrete screws spaced every 16 in. High Density Foam Dance Subfloor Over Concrete If installing a dance floor over concrete, utilize a high density foam as the base layer. Subfloor. Adding a subfloor over the concrete slab is one installation method. Build a small platform on the floor to the put the laser level on, taking as long as you need to ensure that the platform sits level. But doing so is a very laborious, time-consuming process that is likely more trouble than it is worth. Subfloor condition: The subfloor must be free of moisture damage, including rot and sponginess, and must be securely fastened to the joists and squeak-free.Don't lay tiles on a concrete slab with cracks that appear to be spreading or irregularities that prevent you from leveling it. Since It can't move either, it just sits on the first one. Yet this application does make sense, since concrete is heavy, solid, and is typically thought of as an unbending, uncompromising material. Then, I'd build a second frame with same materials but running crosswise. Hi, I have a house in Seattle. Building a framed wood floor over an existing concrete slab can provide the space needed for electric wiring, heat venting, plumbing drain lines and added insulation when remodeling a basement or garage space. It lays directly on top of the waterproof barrier, or combination of barrier and underlayment, to help cushion and insulate. When installed correctly, your concrete over plywood floor will not permit moisture through, will not warp or buckle, and will come with all the benefits of concrete in an easy-to-care-for floor. The ground slopes gently away from the foundation, and the roof overhangs each side by about 2-3'. Building a basement subfloor is not as complex as you may think. 2'x2'x7/8" panels press-fit together, requiring no nailing, gluing or fastening. Building a wood floor over dirt can involve several challenges not found when constructing a wood floor over traditional constructed surfaces, such as concrete, sand or gravel. Do I Need a Subfloor Over a Concrete Slab? If your house is built on a concrete slab, the slab can serve as a base for almost any type of flooring. When the adhesive requires, add … If the slab is in good condition it could be covered by a new layer of leveled concrete. Then fasten 3/4-in. Soil shifts and is affected easily by environmental conditions outside the floor area. If you have a subfloor that consists of wood on top of concrete, you’ll need to test both floors. It's best to place the underlayment over 3/4-inch-thick plywood fastened with screws at 12- to 16-inch intervals to help decrease deflection and add stability. Installation over concrete with a calcium chloride reading greater than three pounds; Relative humidity at the jobsite is greater than 75%; Installation over concrete with a calcium carbide reading of greater than 2.5 percent. Subfloor Installation Guide July 2, 2020 This collection of videos and animations illustrates standard subfloor installation over wood framing and a floating subfloor assembly over a concrete slab (or a 'slabless slab' as the case may be). May 23, 2020 - This article is part of our series on How to Install Hardwood Floors. When gypcrete or concrete underlayment is applied over a standard plywood or OSB subfloor, I don’t recommend using a membrane, which would prohibit the underlayment from … This free video will teach you more about building a basement subfloor. For the plywood, don;t go less then 5/8". This article provides detailed instructions for leveling a subfloor based … And your actual flooring over that. Yes, the best way would be to replace the slab, but.. The concrete subfloor must be sufficiently strong to safely support the flooring, furniture, and people in the room. Check for cracks and crumbling. installing subfloor over un-level basement concrete floor? If your concrete subfloor was just poured, you’ll need to allow it to properly cure for a minimum of 60 days before your luxury vinyl flooring installation begins. … How to level a subfloor before laying tile concrete floors subfloor over uneven concrete floor diy leveling a floor 8 top tips to keep in mind bob vila your guide to installing laminate flooring on an uneven subfloor flooring over concrete batten system you how to choose the right subfloor leveling techniques. Be aware of the additional height that the subfloor and underlayment add. Concrete subfloors might need replacement if they have significant structural cracks or shifting due to an unstable base below or from an earthquake or other natural event. > I want to build a wood floor over the concrete slab. While preparing to lay 1100 square feet of hardwood flooring, we discovered significant variation in the OSB subfloor that will serve as the nailing surface for the hardwoods. 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