What is Carpet Underlay and do I need it?

Stuart Hicks
January 3, 2024

Carpets are some of the most comfortable flooring options on the market, to the point where the best ones feel like they couldn’t possibly get any better. That being said, the Trading Standards Institute (TSI) recommends that every new carpet should come with a new underlay.

In this article, we will go over what a carpet underlay is, why you should have one, and what the best options are.

What is a Carpet Underlay?

A carpet underlay is a layer of material that is placed between the carpet and the subfloor and can be made from a range of materials designed with different benefits in mind. The benefits they give are immense. By installing an underlay, you will improve your floor in the following ways:

Enhanced Comfort

Carpets are already comfortable, but the cushioning and support that a lot of underlays provide can further enhance the experience. This is especially useful in areas where you entertain guests, or in areas such as your bedroom.

Thermal Insulation

This is perhaps the most interesting benefit you gain from your carpet. It’s said that a minimum of 10% of a home’s heat is lost through the floor. As a result, by investing in an insulating underlay, you will save on your energy bills thanks to reduced heat loss.

Improved Appearance

Think of your underlay like the backbone of your carpet, taking most of the brunt of the foot traffic and other heavy objects laid within the room. Your new carpet will stay looking pristine throughout its lifespan thanks to this underlay support.

Sound Insulation

The cushioning of your underlay can also reduce the sound made through footsteps as well, reducing the volume or impact of sound and how far the sound travels. This allows you to relax in comfort, uninterrupted by noise pollution within your own home.

Now that we understand what a carpet underlay does, let's take a look at what they’re made of.

What are Carpet Underlays made of?

Each material that underlay is made from has different benefits.

Foam Underlay - Foam underlays are generally made from polyurethane. These underlays offer excellent comfort and bounce-back abilities. Their lightweight nature makes them easy to install, and depending on the thickness and density, can be used in areas of low to high traffic to best suit your needs.
Rubber Underlay - Rubber underlays are known for their incredible density, being well suited for areas where durability is a concern and can aid sound reduction.. Their high endurance makes them perfect candidates for areas with heavy foot traffic, such as hallways, or for commercial use.
Felt Underlay - Felt underlay used to be made from animal hairs, but nowadays they are made from recycled natural fibres. They are thick and boast good insulation for both temperature and sound.
Crumb Rubber Underlay - Made from recycled rubber, this is an eco-friendly option that also offers excellent durability and noise reduction. This also makes it great for areas of high traffic or areas that require good sound insulation. Due to this, they make a very popular choice for stairs.
Combined Underlay - This type of underlay combines the benefits of different materials to provide an underlay suitable for various applications.

What should I consider when choosing an Underlay?

When selecting carpet underlays, it’s important to consider several key points when figuring out how to choose the most beneficial option.

Suitability

What is the role of the room you’re putting an underlay in? For example, a bedroom is supposed to be a comfortable, restful space, as it’s the place where you sleep. As such, it would be best to go with a PU foam underlay.

Quality

The old saying “buy cheap, buy twice” comes to mind when considering cheaper underlay options. These cheap options will likely have less longevity than a higher-quality underlay.

Underlays have to be seen as an investment. Some underlays are so good that they eventually pay for themselves over their whole life, as a more insulated household will result in less heating bills.

Environmental Impact

The UK has been making major strides towards reducing the impact of some products on the environment. Despite this, some underlays are still made from synthetic materials that are not so easy to dispose of and have a negative impact on the environment.

Thankfully, there are plenty of underlays that are eco-friendly. If environmentalism is a concern to you, consider taking a look at our biodegradable underlays, such as our Breathe underlay, which is made from natural wood fibres and fully biodegradable.

Are Carpet Underlays worth the cost?

On paper, carpet underlays sound fantastic, but many homeowners wonder if it's worth the expense. The fact that it’s out of sight doesn’t help. But those who invest wisely in them always say that the difference is very noticeable, meaning it’s not out of sight, out of mind at all.

Carpet underlays are not just a boost to your comfort, but really, a boost to the carpet’s overall lifespan. They absorb foot traffic and wear and tear for the carpet itself, meaning that the carpet will look fresher and more intact than it would without one after a number of years, maybe even months.

On top of this, the long-term benefits of insulation mean that buying an underlay to counter heat loss will eventually pay for itself. By stopping heat from leaving through the floor, you no longer need to produce as much heat to replace what you’ve lost.

Even lower-cost carpets that would otherwise seem lower in quality can jump up a couple of tiers with the right underlay. This means you can afford to combine an affordable carpet with a good quality underlay to provide a good level of performance to meet your budget.

Those considering whether or not to buy an underlay should bear all of this in mind, as once they’re installed, they can completely change the feel of your home.