Underlayment is the layer of material that sits between the subfloor and the new hardwood flooring. Subflooring is a layer of plywood or engineered wood that sits at the very bottom layer of the flooring.
Simply put, underlayment is a layer of material between your subfloor and your floor. While some flooring comes with the underlayment attached, others will require you to install a separate underlayment. Most of the time, underlayment consists of rubber, cork, foam, or felt.
Purpose of the Underlayment
Flooring underlayment is a thin material that rests between the floor covering above and the subfloor below. Because underlayment is a catchall term, it can take different forms depending on the flooring material is supports.
To protect your new hardwood floor from this kind of moisture, an underlayment is usually highly recommended. While not all underlayments are equipped with a vapor or moisture barriers, the best ones are. It will protect your hardwood floor from moisture penetrating inside and potentially ruin them.
If you are using plywood for your subfloor, you should use a minimum of one layer that is between ¾” and ⅝” thick. This thickness will suffice for most floors; however, codes will vary and a second layer is a good idea if your floor covering is going to be a heavy material like ceramic tiles or natural stone.
Underlayment: Some types of flooring can be installed directly on top of the subfloor, such as vinyl flooring. Other types need a middle layer, called underlayment, such as laminate,carpet and tile.
For subflooring, you use tongue and groove plywood. The tongue and groove are only along the 8 foot edges. On the four foot edges, your seams will fall on joist tops, so no need for tongue and groove. But to start off, we will need to remove the tongue so the plywood is tight with the exterior ICF walls.
A wooden or plywood subfloor also requires a moisture barrier as it can trap moisture over time leading to the growth of mould between the subfloor and the hardwood surface. If a protection isn't used, moisture can cause the subfloor to rot gradually.
If the subfloor in your home or property is uneven, then your laminate floor could move and shift if it doesn't have an underlayment for support. As a result, the floor will be more prone to wear-and-tear and could even warp. The more stability, the less likely you'll have to pay out of pocket for costly repairs.
Do I need a vapor barrier for hardwood floors?" The answer is YES! Moisture can destroy hardwood flooring. It causes cupping, warping, and even mildew if not treated. You must install a moisture barrier to protect your flooring from water wicking up from below.
The subfloor is the bottom most structure of the floor. It provides a flat and stable surface and supports the actual floor. Underlayment is different from the subfloor in that it rests between the subfloor and the actual floor.
Yes, you can use pine subfloors as primary flooring. In many older houses, the pine subfloor was the only floor and it held up well. Uncovered pine subflooring appeals to recycling enthusiasts as well as fans of distressed wood.
In a typical home, the entire structure between levels can be about 12 to 14 inches thick, depending on the type of joists used and the finish materials for the floor and ceiling.
Yes, you can install over an existing wood floor, provided it meets some important conditions. First, make sure doing so won't create problems with height differences at areas such as transitions with other rooms and stairs.
The most basic underlayment is a plastic sheet that acts as a moisture barrier. In humid climates, pair a plastic sheet with all other types of underlayments, even those that already offer some moisture resistance. Dealing with warped or mildew-laden wood costs more than adding that extra layer of protection.
If you're laying the LVP over an existing cushion-backed vinyl floor or a below-grade tile floor, then you won't need to use an underlayment. However, you'll want to use one in every other application including covering existing hardwood floors, vinyl flooring that isn't cushioned, and concrete floors.
Underlayment for laminate flooring is a must. Since laminate is a floating floor, it must be evenly distributed across your subfloor. Underlayment is what allows the floor to float, gives it stability, support, noise reduction, and supports the locking systems in between planks to assure the sturdiest flooring project.
Carpet underlay is an excellent insulation tool for your home. Because it is an extra layer between your carpet and the subfloor it acts as a new insulative layer. This then leads to a reduction in heat loss which in turn will mean you can save money on your heating and energy bills.
Therefore, because concrete is porous, it's a good idea to install a vapor barrier over your concrete subfloor before installing your flooring. This way you can stop the vapor drive of water upward to your floors, protecting them from any damage (source).
Manufacturers Require a Vapor Barrier
Your plywood subfloor may look dry, but after you install the flooring, moisture can migrate up through the subfloor and penetrate the flooring, and the results are usually disastrous.
When installing wood flooring, solid or engineered, on a concrete base the use of a damp proof membrane is always recommended. No matter how dry your floor feels it will always contain damp, which can be drawn to the wood if not treated causing cupping, lifting and general damage to the floor.
Ideally, nail down your subfloor using corrosion-resistant nails that will securely hold it in place and last a long time. Screws are a great alternative that you can easily remove, but they are not as sturdy. Screws are superior in terms of reducing floor squeaks, but the installation is slower.
The National Tile Contractors Association and the Resilient Floor Covering Institute both recommend plywood for subflooring and underlayment, because it doesn't have the risk of swollen edges that OSB does. Plywood also has a slight advantage in stiffness, which means that subflooring panels need not be quite as thick.
A wood subfloor should be OSB or plywood of 3/4″ or thicker for a hardwood floor installation. Particle board and chipboard are unacceptable for solid hardwood installations, but may be used in an engineered flooring install.