Best Underlayment for Hardwood Flooring

When installing underlayment, you can still hear the occasional voice telling you that it’s unnecessary, especially if the subfloor is in good condition. However, if you decide to install hardwood floors, listening to these claims will not serve you well in the long run.

Although hardwood floors are renowned for their durability and longevity, they are also susceptible to environmental factors like humidity and temperature fluctuations.

So, despite some claims, hardwood flooring requires specific underlayment if you want to avoid issues like warping or creaking over time. 

Besides, installing proper underlayment for your hardwood floors will serve multiple important functions that go beyond preserving your hardwood structural integrity:

• It manages expansion and contraction
• It provides a moisture barrier
• It reduces noise
• It also provides additional underfoot comfort

It is also true that hardwood needs a different type of underlayment compared to materials like luxury vinyl plank or laminate, and it mainly utilizes materials such as felt or rubber. 

Now that we have settled that underlayment is necessary if you want to get the most out of your hardwood floors, let’s take a look at what characterizes the best hardwood underlayment.

What to Look for in Hardwood Underlayment

There are plenty of underlayments to choose from, but given the specific needs of hardwood, it’s best if the underlayment for your hardwood floors matches the following criteria:

1. Moisture protection: It goes without saying that the first thing you want from your underlayment is to protect your hardwood from water. Look for a perm rating of 1.5 or less, with less than 0.7 being ideal or even necessary if you plan on installing hardwood over concrete or in moisture prone areas like basements.
2. Right thickness: Underlayments usually come in 1/8″ to 1/4″ thick. For hardwood, aim for at least 1/8″ thick, with 3/16″ being optimal for most situations, as it provides a good balance of cushioning and noise reduction without raising the floor too much.
3. Sound reduction: For Impact Insulation Class (IIC), look for a minimum of 50, with 60 or higher being excellent. For Sound Transmission Class (STC), aim for at least 50, with 60+ being ideal.
4. Heat insulation: If you live in colder climates, you will be especially interested in your underlayment heat insulation efficiency (R-value). For hardwood, look for a minimum R-value of 0.2, with 0.5 or higher being optimal for warmth and energy efficiency.
5. Ability to stay firm: Hardwood flooring can last decades, and you want the same from your underlay. Compression resistance rating (CR) measures how well underlayment maintains its thickness over time. Look for a CR of at least 16 kPa (kilopascals), with 30 kPa or higher being excellent.
6. Some breathability: While you want to keep moisture out, a little airflow can help dry out any trapped moisture. For hardwood, cork and felt underlayments offer a good balance. Cork typically has a perm rating of 2-3, while felt can range from 0.5 to 5 perms, depending on the specific product.

So, having all of these requirements in mind, ticking all the boxes for perfect underlayment might be a bit of a tall order, but there are underlayments that are close to being ideal in every aspect. The degree to which you are willing to compensate is entirely up to you and your specific needs. Maybe you live in a dry and warm area, so there is no need for strong R-values or perm ratings.

In any case, let’s move on to 5 best underlayments for hardwood floors.

#1 QuietWalk Plus

This one checks a lot of boxes:

• Moisture Protection: It comes with a built-in vapor barrier and has a low perm rating, so it is suitable for installations over concrete or in moisture-prone areas.
• Thickness: Around 3/16” thick, which hits the sweet spot for cushioning and noise reduction.
• Sound Reduction: IIC of 71 and STC of 66—both excellent ratings for soundproofing.
• Heat Insulation: An R-value of about 0.58, so it’s solid for colder climates.
• Compression Resistance: Offers decent compression resistance, though exact kPa numbers aren’t always available.
• Breathability: It has some breathability, but not as much as cork or felt, though this is balanced out by its vapor barrier.

This is a great all-around choice. It offers excellent moisture protection, soundproofing, and heat insulation. The only downside is its lower breathability, but it’s still the best option for multi-story homes and apartments where noise reduction is important.

#2 Cork Underlayment + Vapor Barrier Combo

You can pair a cork underlayment with a separate vapor barrier to meet most of your needs:

• Moisture Protection: Cork alone doesn’t block moisture well, but when paired with a dedicated vapor barrier (which typically has a perm rating under 0.5), it becomes suitable for basements or concrete.
• Thickness: Comes in various thicknesses—usually 1/8” to 1/4”—so you can dial in the comfort and sound absorption.
• Sound Reduction: IIC ratings for cork can reach 60+, with STC ratings often in the same range.
• Heat Insulation: Cork has an R-value of around 0.5 or higher, so it’s a great insulator.
• Compression Resistance: Cork is durable and keeps its shape well, though it may not have as high a kPa rating as some synthetic options.
• Breathability: Cork has a natural perm rating of 2-3, so it allows for a little airflow, which can be a plus for hardwood.

Cork works best for buyers who want strong sound and heat insulation with eco-friendly materials. It doesn’t block moisture on its own, so you need a vapor barrier, which adds cost and effort. However, it’s the best option for cold climates.

#3 Floorlot Gold Premium Underlayment

This synthetic underlayment is another strong contender:

• Moisture Protection: Features a vapor barrier with a perm rating under 0.7.
• Thickness: Typically around 3/16”, so it provides a good balance of cushioning and sound reduction.
• Sound Reduction: IIC around 67, STC around 66, excellent for soundproofing.
• Heat Insulation: R-value of 0.58, similar to QuietWalk.
• Compression Resistance: Offers good CR, though specifics may vary.
• Breathability: It doesn’t have as much breathability as cork or felt, but the vapor barrier adds serious moisture protection.

This underlayment delivers good results across moisture protection, soundproofing, and insulation. It doesn’t provide much breathability, but it’s a solid, easy-to-use choice when airflow isn’t a big concern.

#4 Roberts Super Felt Underlayment

Roberts Super Felt is an eco-friendly option that’s made from recycled fibers.

• Moisture Protection: While not as moisture-resistant as some options, it’s breathable, which helps release any trapped moisture. You can pair it with a vapor barrier if installed over concrete or in moisture-prone areas.

• Thickness: Its 3mm (1/8″) thickness provides a decent balance between comfort and floor height.

• Sound Reduction: A respectable rating of IIC of 66 and STC of 67 makes it a solid contender for soundproofing between floors, and it works well in apartments or multi-story homes.

• Heat Insulation: The R-value stands lower than that of its counterparts, at about 0.33, but it still provides some insulation to help with temperature control.

• Compression Resistance: Felt underlayment is known to be very durable, and it easily maintains its thickness under heavy foot traffic or on furniture.

• Breathability: The felt material, while not the most breathable underlayment around, still allows for some air circulation, which is enough to prevent trapped moisture and mold growth.

Roberts Super Felt is perfect for dry climates with its solid soundproofing and durability. It doesn’t protect well against moisture, so you will need a vapor barrier in wet areas or over concrete.

#5 MP Global Insulayment

Insulayment by MP Global is another great all-around underlayment designed to work well under hardwood, engineered wood, and laminate flooring.

• Moisture Protection: While insulation itself is not a vapor barrier, it does provide moderate moisture resistance. Like cork, you can pair it with a separate vapor barrier for installation over concrete.
• Thickness: It’s 3mm (about 1/8″) thick, similar to the Roberts Super Felt. It strikes a good balance between thickness and comfort.
• Sound Reduction: Excellent IIC rating of 73 and STC of 67, providing superior noise reduction—great for multi-floor setups where soundproofing is essential.
• Heat Insulation: It has a 0.6 R-value, which makes it the most efficient insulator on this list. MP Global is great for colder climates and energy efficiency.
• Compression Resistance: Insulayment is highly durable and offers solid compression resistance, ensuring that it doesn’t lose shape under heavy furniture or high-traffic areas.
• Breathability: It provides some airflow, which helps prevent moisture buildup, though it’s not as breathable as felt or cork.

This is the best choice for soundproofing and heat insulation in cold or noisy spaces. It needs a vapor barrier to handle moisture, which adds an extra step, but it performs well in every other area.

Conclusion

As we already established, installing the underlayment for hardwood floors is non-negotiable. This list provides solutions that provide good all-around answers, with some being slightly better than others in certain areas.

In most situations, you won’t go wrong with either of these solutions for your hardwood floors, but you can still pick carefully if you want to take advantage of their specific properties or mitigate some of their weak points.

Either way, this list provides you with a starting point for finding the best underlayment for hardwood floors, and your choice will always depend on your specific needs and circumstances.