Do I Need Underlayment for Vinyl Plank Flooring

What Exactly is Underlayment?

Your flooring is composed of a variety of important elements that contribute to its overall function. Structurally, you have joists that are laid at the beginning of the construction process and support the weight of the flooring. On top of the joists rests the subfloor, which can be made of a variety of materials, but most commonly plywood.

Underlay sits on top of the subfloor and rests beneath the finish floor (hardwood, plank flooring, carpeting, etc). Underlay is not structural, however, it serves a variety of important functions.

In some cases underlayment is optional, and this decision depends on various factors that we’ll address further down in this article. For now, we’ll discuss the advantages that underlayment provides.

Source: The Spruce

Benefits of Installing Underlay in Your Flooring Project

While underlay doesn’t help support the weight of the flooring, or serve any structural purpose, it’s still quite useful, and can affordably be purchased by the square foot. There are numerous benefits that underlayment provides, including:

• Floor Softening: Unless you’re installing carpeting, the flooring you put into your home is likely quite hard. When hardwood and luxury vinyl planks are installed directly on the subfloor, there’s zero cushion between the materials. Adding underlay allows your flooring to “bounce” a little as you walk across it, softening how it feels beneath your feet.
• Sound Reduction: When your flooring is installed directly on the subfloor, friction is created every time you step on it. When these two materials rub together, it can cause squeaking. Underlayment creates a barrier between them, promoting noise reduction in your home.
• Moisture Protection: Many underlayments creates a moisture barrier between your home and the subfloor. This is crucial as water can damage the integrity of plywood.
• Insulation: A thick underlay provides insulation properties that can help keep your floors warmer in the winter. Your subfloor can become quite cold during the colder months, and having an underlay adds insulation that keeps the cold out. Underlay mitigates this.
• Better Installation: Underlayment provides a smooth surface that has less friction than the plywood or concrete subfloor, making it easier to slide and position the flooring when using a click-together installation.

Source: Hunker

When Do I Need Underlayment for Vinyl Plank Flooring?

There are a variety of considerations to make when deciding whether or not you’ll need to underlay your vinyl plank flooring installation. While the benefits discussed are tough to beat, in some circumstances you don’t technically need underlayment.

Depending on your type of subfloor or the flooring you’re installing vinyl on top of, you may or may not need underlayment. The type of flooring also determines which type of underlayment you should buy if it’s needed. Different types of subfloors have different properties that may warrant one style of underlayment over another, and different installation methods have different underlayment needs. Stick-on, glue down, and loose lay vinyl don’t require an underlay. It’s always best to check with the manufacturer, or flooring dealer, and follow their recommendations.

Finally, some luxury vinyl planks come with a built-in underlayment that provides sound dampening and softening qualities. In this case, you’ll only need to install moisture and vapor barriers if installed over damp surfaces like concrete.

Do I Need Underlayment for Vinyl Plank Flooring on Concrete?

If your home’s subfloor is made of concrete, you will absolutely need an underlayment if installing luxury vinyl plank flooring. While concrete is an exceptionally durable construction material, it has a few inherent properties that don’t play nicely with the flooring of your home. The reasons why concrete needs underlayment includes:

• Moisture Secretion: Concrete is naturally porous, meaning moisture, humidity, and vapors can travel right through it. Moisture is always moving within the concrete, and the material can secrete from it over time. This may result in mold that can be particularly damaging to your home. If installing over concrete, use a underlayment that has a moisture barrier built in.
• Hard Material: If vinyl plank flooring is installed directly on the concrete, it will be incredibly stiff to walk on. Adding an underlayment made of foam, cork, or rubber will allow some suspension beneath your feet as you enjoy the home.
• Thermal Regulation: Concrete is exceptionally cold in the winter, and this can cause the flooring in your home to be uncomfortably cold as well. Underlay will help block the coolness that comes off of the concrete.
  
  

Do I Need Underlay for Vinyl Plank Floor Installed Over Ceramic Tile?

Unlike concrete, an underlayment is not an absolute necessity for installing vinyl plank floors over ceramic tile, however, it is still highly recommended. Tile has some properties to it that can benefit from installing an underlay and will allow you to enjoy your vinyl flooring more thoroughly.

When looking for the proper underlayment for tile, you won’t need to worry about a product with moisture protection. Tile doesn’t secrete any water as concrete does, so there is less of a risk of mold caused from moisture.

Tile is a hard surface though, and you’ll experience the same stiffness as concrete when vinyl flooring is installed directly to it. Consider adding underlay simply for the cushion it provides. Tile can also be cold in the winter, so the insulation benefits of an underlayment apply as well.

One main advantage of installing an underlay between tile and vinyl is that it skips the need to fill in the grout lines. You’ll need to choose a thicker underlay option to keep those grout lines from showing through the vinyl floor. If you choose not to install an underlay, every single grout line will need to be leveled to meet the rest of the floor.