Choose the Best Underlayment for Laminate Flooring

The selection and proper installment of underlayment for laminate flooring is important for several reasons. The underlayment can affect how the floor feels and how it wears over time. Using the wrong underlayment or improper installation can also void the flooring manufacturer's warranty. The type of underlayment chosen should be based on the environment, the type of floor chosen, and how you'd like the floor to perform. The underlayment (and the subfloor below it) should be level and smooth to achieve an even finish on the laminate flooring. Read on to learn about the best underlayment for laminate flooring that can meet your needs.

What Is Laminate Flooring Underlayment?

Laminate flooring underlayment is a thin, flexible sheet of resilient material that is installed on top of a subfloor. It acts as a base for the laminate planks or tiles you're installing. Laminate flooring underlayment will support, enhance, and protect the flooring material in several ways. It will slightly level the flooring, cushion the laminate planks, reduce sound transmission; and slightly improve the floor's R-value (its resistance to heat transmission).

Laminate Floor Underlayment Considerations

Subfloor

Concrete subfloors: When installing over a concrete subfloor, the main concern is moisture. Concrete is a porous material that can allow water to seep up into it and through to your flooring. This can cause adhesives to loosen, flooring planks to warp, and mold and mildew to develop. With a concrete subfloor, you will need an underlayment that acts as a vapor barrier to prevent moisture from penetrating through to your laminate installation. The normal choice is a thin foam pad material made of polyethylene or polypropylene, which rolls out in sheets.

Plywood subfloors: A breathable foam-type underlayment is generally used when installing laminate flooring over plywood or OSB subfloors. In most cases, you will not want to use a vapor-barrier-type underlayment when installing laminates on a standard plywood subfloor, because wood is a natural material that needs to breathe. Installing a vapor barrier over this can cause moisture to become trapped within the material, leading to the growth of mold or warping in the material. The exception is when laminate flooring is being installed in a high moisture area, such as a bathroom or basement, where a moisture barrier underlayment is a good idea.

Noise Reduction

Some types of underlayment can act as a barrier to the transmission of noise. This can be important in certain working environments where silence is necessary, or in bedrooms where peace and quiet are preferred. Laminates can be noisy floors, and a good underlayment will help deaden the sound transmission.

Insulation

The R-value refers to the heat conductivity of a given material. The higher the R-value of the underlayment, the less heat will be able to move through it, while the lower the R-value is, the less insulation the underlayment provides. A high R-value underlayment will make the floor feel warmer underfoot in the winter.

Cost

Higher-quality laminate flooring underlayment will typically extend the lifespan of your flooring versus budget underlayment. Low-cost underlayment materials may not be as durable or perform as well as more expensive products. Plan to spend as much as you can on underlayment materials and buy underlayment that is warrantied in case the floor fails due to the material. Underlayment typically comes in 100 or 200-square-foot rolls costing about $20 to $40 or more per roll, depending on the size and type of underlayment you want. For example, if your room is 350 square feet, you will likely need four 100-square-foot or two 200-square-foot rolls of underlayment.

Thickness

Standard underlayment for laminate flooring will typically be a minimum of 3mm thick (1/8 inch). There are simple 2mm foam underlayment products without damp-proof membranes (DPM) and should only be used in selective and dry environments. The maximum thickness of underlayment for laminate flooring may run 5 to 6mm.

But underlayment that is too thick or soft is not always better. Very thick underlayment will lead to an unstable flooring installation. The instability can result in damage to the locking system, and planks that buckle and separate. Also, avoid using two layers of underlayment. Manufacturers have designed underlayment systems to work as a single layer under laminate flooring.

Types of Laminate Underlayment

Do not use carpet padding or another soft, thick underlayment to increase the comfort of a laminate floor or the installation will flex, resulting in loosened joints. The proper underlayments to use when installing laminate flooring are very thin foam layers that slightly cushion the flooring but won't allow noticeable movement underfoot. These products are applied over the subfloor by rolling them out and sealing the seams with adhesive strips, which are sometimes preattached to the underlayment. There are three types:

• Standard foam underlayment: The most common form of laminate underlayment is this thin layer of cushioning foam material placed between plywood/OSB subfloors and laminate flooring. However, it should never be used in high-moisture areas because it does not provide any vapor barrier characteristics. Standard foam underlayment is installed by rolling it out over the subfloor.
• Combination foam underlayment: This type of underlayment combines standard foam with a vapor barrier layer that protects the installation from moisture. It is slightly more expensive than standard foam. A combination underlayment is appropriate for both plywood/OSB and concrete subfloors and can be used in most environments, including moist locations, such as basements and bathrooms.
• Cork underlayment: This material is used for noise reduction. Cork is expensive, sometimes adding as much as 50 percent to the cost of a laminate flooring installation. It does not provide any more cushioning or comfort underneath the laminate but it can level out uneven surfaces between rooms and it has natural antimicrobial characteristics.

Laminate Flooring With Attached Underlayment

Today you can find many laminate floors that have been manufactured with underlayment padding built into the underside of the material. With these materials, you do not need to purchase and install a separate foam padding underlayment. In most cases, these flooring materials are installed directly over the plywood or OSB subfloor. Some types are also suitable for wet locations without an additional vapor barrier seal.