What Is The Best Underlayment For Hardwood Floors? Here's What We Know

When you're looking for a new flooring option in your home, there are plenty of reasons why hardwood is the right choice. It offers multiple benefits, including significant durability, a beautiful look, and increased home value.

If you're installing hardwood yourself, you'll probably need to select an underlayment material. Without some sort of padding beneath your hardwood floors, they might have an overly firm, unforgiving feel. When laying your hardwood planks over a common type of subfloor, such as plywood or oriented strand board (OSB), you have two extremely firm materials back to back. Adding an underlayment material between them delivers key benefits like sound dampening and compression resistance. If necessary, you can even combine the underlayment with some sort of waterproof material to create a vapor and moisture barrier, which will keep your hardwood safe from warping.

When selecting the proper underlayment for your hardwood installation, match the type of material you're using to the specific conditions you expect, as some options work better in certain situations than others. The right underlayment — whether it's foam, rubber, felt, or cork — can reduce sound, deliver thermal regulation, and provide cushioning. You might even need a material that combines all of these benefits. The right underlayment makes all the difference for a hardwood floor. Let's learn more about the different options you have for installing this critical layer.

After you install hardwood flooring, the sound of footsteps can become quite loud for the level beneath. Additionally, the firm hardwood might allow sound to echo throughout the space, possibly disturbing other residents. When installed correctly, underlayments can reduce sounds like these from the hardwood. To do its job correctly, the underlayment material must fit between two firmer materials, such as the hardwood above and OSB or plywood underneath. You have a few options for underlayment materials that successfully reduce noise, including foam, felt, rubber, and cork.

A shredded rubber mat is a strong choice for absorbing household noise. Because it's a heavier material than some other noise-resistant options, it offers significant soundproofing capabilities as an underlayment. Cork, on the other hand, is a highly durable material that frequently appears in commercial layouts. Don't worry, though — residential users can deploy it, too. In fact, it's a particularly eco-friendly option thanks to its sustainability. Cork is useful as a soundproofing material because its natural air pockets can absorb sound waves. Lightweight, closed-cell foam is another strong option, as it works to reduce impact noises and their echoes throughout the home. If your primary concern is minimizing the noise traveling from your hardwood floor to the rooms beneath it, felt underlayment is one of the best materials for blocking noise between home levels, and it's a popular selection in areas with significant foot traffic.

If you're installing hardwood over a bare concrete floor, a garage, an unheated basement, or a crawl space, you might have some concerns about the hardwood feeling cold. Fortunately, certain underlayment materials can act as a thermal barrier, preventing the hardwood from feeling frigid to the touch. Cork and felt, once again, are two of the best underlayment materials to use for hardwood thermal protection.

A cork underlayment works especially well as a thermal barrier (and has for centuries). Whether the hardwood flooring is above or below grade, cork makes it feel warmer. To achieve the best results with cork underlayment, consider material that's 6 millimeters in thickness (or about ¼ inch). Because cork has a honeycomb structure with air pockets, its thermal conductivity value is low. Cork also works well because of its ability to maintain its thermal conductivity properties across a wide range of temperatures.

Felt also works well as a thermal insulator for hardwood floors. Its R-value (which measures different materials' resistance to heat flow) is around 0.6, which is almost double the R-value of foam underlayment. Although wool felt is a common underlay for carpeting or roofs (where it's usually saturated with asphalt), it has excellent thermal properties for hardwood floors, too. Felt is an especially good choice if you're installing hardwood over a concrete subfloor.

When covering a hard subfloor with hardwood planks, underlayment can provide a bit of cushioning between these two firm materials. The right underlayment — which may be foam, rubber, felt, or cork — delivers an extra layer of cushioning, making the floor more comfortable for walking and other activities.

Foam underlayment provides a high level of cushioning, especially if you select a thicker type of foam. However, avoid using foam that's too thick, or it could compress too much and harm the hardwood's stability. Even though foam provides comfort when used as an underlayment, it will tend to compress over time, meaning its cushioning ability will eventually drop. Felt delivers a high level of cushioning, too, especially compared to some other underlayment materials. Felt tends to maintain its resilience, giving you a nice level of comfort for a longer duration than foam can offer.

Rubber and cork are firmer materials that can withstand quite a bit of weight while providing cushioning. However, neither quite has the same cushioning properties as foam or felt. Rubber does offer a cushioning effect as underlayment that makes the hardwood floor slightly more comfortable for walking or sitting. Cork is firm, too, but it naturally provides a strong cushioning effect that's helpful beneath hardwood. The honeycomb-shaped cells inside cork underlayment compress against one another, creating an almost springy feel underfoot.