on center. Before installing a thin concrete or gypcrete floor over a plywood subfloor, what kind of membrane should be installed over the plywood? Check for cracks and crumbling. 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. 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. 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. 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. Building a basement subfloor is not as complex as you may think. 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. Let's assume there is no gravel, sand, plastic, or insulation underneath the slab. Be aware of the additional height that the subfloor and underlayment add. How to Install a False Floor Over a Basement Slab. Over time, a sink or refrigerator water leak can damage and even destroy flooring materials and the subfloor below it. And it's a great way to turn an old concrete floor into something nice! 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. 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. Undecided about the best way to cover and warm up the concrete floor in your basement? A decorative concrete flooring material can be installed over an existing concrete slab, a plywood subfloor or a 3/4-inch solid hardwood flooring. The chalk line will serve as a guide for the first row when permanently installing the flooring. Leave a small air space between the concrete and the plywood. If the slab is in good condition it could be covered by a new layer of leveled concrete. The concrete subfloor must be sufficiently strong to safely support the flooring, furniture, and people in the room. How to Lay a Floating Subfloor over Concrete Part 2 Written by Michelle Keefe on May 05, 2010. 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. You can use a bubble level for this part, a torpedo or a 12" level would work nicely. False floors, also known as floating floors, are not permanently attached to the floor or walls. Then, I'd build a second frame with same materials but running crosswise. Lay 6-mil polyethylene sheeting over the concrete to minimize moisture migration from the concrete up into the wood flooring. Hi, I have a house in Seattle. Yet this application does make sense, since concrete is heavy, solid, and is typically thought of as an unbending, uncompromising material. installing subfloor over un-level basement concrete floor? A subfloor warms finished floors by 6°F (3.2°C) and provides protection from moisture. The ground slopes gently away from the foundation, and the roof overhangs each side by about 2-3'. Then install your subfloor over that once your floor is level. You don't want the plywood resting on the concrete because it will rot. Air gap subfloor panels elevate and insulate your finished floor quickly and easily. When it comes to solid wood, both strip and plank flooring are acceptable as long as they are in good condition. … 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). 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. Install a vapor barrier of plastic sheeting before laying the subfloor. Adding a subfloor over the concrete slab is one installation method. 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. Concrete floor video on how to install concrete over an existing wood subfloor. 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