Underlay buying guide

Underlay is the foundation for your flooring. While it’s invisible after fitting, its effects are clear as day! Good underlay can improve everything from how flooring feels underfoot, to how to it wears and maintains its looks over time.  

Because it’s so fundamental to flooring, we pride ourselves on being underlay experts. We know everything there is to know about underlay and how to pick the best one for your home.

Investing in your underlay can increase the lifespan of your flooring by 30-50%! It’s far from an optional extra – it can even save you money in the long run. 

If you’re getting new flooring, you usually need new underlay. Using underlay that’s worn down can show wear more quickly, especially in high traffic areas, and over time wear the carpet down unevenly. It will harbour dirt and dust and should be replaced when installing new carpets.

With the help of our experts, we’ve created this buying guide to make it easier for you to find the right underlay for your floor. Let our new home expert, Lucy Alexander take you through our four easy steps to the perfect floor in the video below.

Why choose underlay?

Why choose underlay? Why choose underlay?

Sometimes overlooked and even dismissed as a pointless additional expense, underlay is actually an integral element that shapes how flooring feels, wears and looks. It’s key to the finish of your floor and the longevity of your flooring. Getting the right underlay will ensure you get your money’s worth!


• adds a cushioned depth of comfort underfoot

• acts like a shock absorber, protecting the condition of your floor

• acts as a barrier against noise and helps with soundproofing

• acts as an insulator and could save you money on your energy bills!

Underlay adds a level of cushioning underneath your carpet, luxury vinyl, laminate or wood flooring making it much more comfortable to walk on.

Underlay can also help reduce your energy bills as it traps heat under your floor, insulating the room and keeping it warm. This insulation doesn’t just stop at heat though, underlay also helps to insulate against sound, keeping in-room noise to a minimum which can be a great benefit for upstairs rooms or if you live in a flat.

It’s important to note that there is more than one kind of underlay. Read on to discover the underlay that will suit your room and flooring type best.

Types of carpet underlay

There are lots of underlay types, meant for use with different flooring and for different rooms. Carpet underlay acts like a shock absorber, helping carpets bounce back from heavy wear and footfall. Your carpet will look better for longer because the underlay helps prevent the pile from flattening. Below are the different types of carpet underlay available.

Polyurethane Underlay Polyurethane Underlay



Most of the underlay sold used to be made from rubber. This has been overtaken by polyurethane, usually called “PU”. It’s made from offcuts or from foam that’s been recycled. What’s great about PU is that it comes in different thicknesses and densities to suit all floors and budgets. It’s a great all-rounder.

Sponge Rubber Underlay Sponge Rubber Underlay

Sponge rubber


Sponge rubber underlay is still popular although nowadays it’s made from synthetic rather than natural rubber. It can give a really luxurious and comfortable feel. Available in various thicknesses this underlay is great for use all around the home. Choose a super thick version to bring comfort and luxury to your lounge or master bedroom. Guaranteed for the lifetime of the carpet.

If you have underfloor heating you need to consider the tog rating of your underlay. Just like when you are choosing a quilt, the tog rating measures how easily heat can pass though. We have a special underlay with a low tog rating designed for use with underfloor heating.

Crumb Rubber Underlay Crumb Rubber Underlay

Crumb rubber


This underlay is dense and durable and ideal for use all around the home including areas that have to cope with lots of traffic like the hall, stairs and landing.

Every square metre of underlay contains at least one car tyre! It’s the number one choice for heavy wear areas and best for maintaining the look of your new carpet. Guaranteed for the lifetime of the carpet.

Felt/Crumb Rubber Combination Image Underlay Felt/Crumb Rubber Combination Image Underlay

Felt/Crumb rubber combination


This underlay combines the comfort of felt with the resilience of crumb rubber with every square metre of rubber containing at least one car tyre! It’s excellent for both sound and heat insulation and perfect for use in all rooms. It’s suitable for use with woven Axminster and Wilton carpets.

Types of hard flooring underlay

Underlay for hard flooring; like laminate, wood flooring or luxury vinyl; helps to protect the joints in the planks or tiles, reducing any risk of flexing to extend the life of your flooring. Below are the different types of hard flooring underlay available.

Luxury Vinyl Tile Underlay Luxury Vinyl Tile Underlay

Luxury vinyl tile


This underlay made specifically for use with luxury vinyl is constructed from dense rubber. The top side is slightly tacky which helps to prevent the vinyl from slipping when it’s installed. Perfect for use with underfloor heating, this underlay improves sound insulation reducing in-room noise by up to 30%.

Stepshield Underlay Stepshield Underlay



This moisture proof underlay also provides great sound insulation and is designed specifically for use with laminate or wood flooring. Made from foam, this easy to install underlay will help to cover minor sub-floor irregularities of up to 1.5mm and is suitable for general domestic use.

Timbershield Underlay Timbershield Underlay



This underlay for wood and laminate flooring is constructed from a highly dense, heavy-duty synthetic rubber and has a fleece backing that provides extra stability and insulation. With its exceptional resistance to compression, this underlay reduces any risk of flexing making your wood flooring joints super secure, even if you’re using super heavy furniture. Suitable for heavy domestic use around the home.

Thermabreathe Underlay Thermabreathe Underlay

Low thermal resistance


Perfect for use with underfloor heating, Heatflow underlays are made from rubber with a low tog rating. This enables heat to flow freely through them into the room increasing energy efficiency and reducing bills. This underlay is available in two types for either carpet or wood flooring and is great for sound insulating too.

Understanding tog ratings

Understanding Tog Ratings Understanding Tog Ratings

You may associate tog ratings with bedding, but they’re just as relevant when it comes to underlay. Thickness, density and composition dictate the tog rating of a carpet or underlay and they vary widely. A tog rating is a measure of heat insulation and when it comes to flooring it’s a great indicator of which underlay is good for use with underfloor heating.

The lower the tog rating the better in these scenarios because more heat can rise up through the flooring and into the room. We would only recommend a maximum tog rating of 2.5 for underlay and carpet combined for use with underfloor heating.

A higher tog rating on the other hand means greater levels of heat insulation, which is perfect for use with conventional heating systems, as less heat gets lost through the floor, keeping rooms cosier.

Finding your ideal underlay

Free samples Free samples

Free sample service


Order up to four free samples online and we’ll deliver them straight to your door within seven working days. Find the best underlay for your flooring without even leaving home!


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Underlay Testing Station Underlay Testing Station

Underlay testing station


Visit us in-store where you can try out different underlays under carpets and other flooring for yourself. Our underlay testing station is the best way to feel the squish and comfort that good underlay can bring to your flooring.


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Free home consultation


Book a free home appointment for accurate measuring and advice from our dedicated flooring experts on the best flooring types, underlay and accessories for your rooms.


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