What is a good thickness for underlay?

Author: Miss Elvie Sporer  |  Last update: Monday, June 9, 2025

This goes to show that you shouldn't always assume that thicker is better. 9-10mm carpet underlays are usually good all-rounders that can be installed in all areas of the home, including stairs and hallways. Offering high levels of comfort, insulation and soundproofing, they represent excellent value for money.

What thickness underlay is best?

So generally speaking 7mm is about as thin as you want to go unless you have a specialist need for something thinner, but 8-12mm is the band most manufacturers produce carpet underlay with and its perfect for any room and any carpet.

How thick should your underlayment be?

With that being said, most underlayments are 2-3mm thick, but are sometimes thicker for carpet or to smooth out an uneven subfloor. It's often advertised that 6mm underlayment offers double the sound absorption as 3mm underlayment.

Is 2mm underlay ok for laminate flooring?

Our 2mm Foam Laminate and Wood Flooring Underlay is our low cost underlay which is suitable for all types of wood and laminate flooring. It is also suitable for use on wooden and concrete subfloors.

Is 5mm underlay too thick for laminate?

You wouldn't want to use underlay any thicker than 5mm anyway. 7mm underlay WOULD in fact make a huge difference in the stabilisation of the laminate and in time will possibly cause you more problems with the laminate locking together properly.

Best Carpet and Underlay Thickness

Is 7mm underlay any good?

A 7mm standard quality foam underlay would be considered a budget price option, whereas a high density 8mm to 12mm would be regarded as a good option to give great support to your new carpet.

Can you use 2 layers of underlay under laminate flooring?

Remember that your underlay needs to be as smooth as possible. So, never put two layers on top of each other: this will create unevenness. Immediately secure the first sheets of underlay with a laminate board and work towards the wall.

What underlay is best for laminate?

If you're looking for an affordable underlay to fit under a wood or laminate floor, foam underlay is the way to go. It's comfortable to walk on, provides cushioning underfoot, absorbs sound and does a great job of keeping your room warm.

How many mm is good for laminate flooring?

10mm – 12mm laminate thickness

10mm thickness is where manufacturers really start to take things seriously. It's where most of the performance problems that come with thinner laminate are eliminated.

Is expensive underlayment worth it?

The high cost of synthetic underlayment is due to its superior material strength and long lifespan compared to felt or asphalt paper underlayment. While the initial investment may be higher, synthetic underlayment can save you money in the long run by lasting longer and requiring fewer repairs or replacements.

Can you have too much underlayment?

More is not always better, and with underlayment, too much can compromise the integrity of your floor's locking system. Adding additional underlayment under vinyl with an attached pad can create too much cushioning, which causes the floor to come apart through use over time.

Is 2mm underlayment enough?

1-2mm underlay is typically a budget option that offers a basic layer of protection for your laminate. It will help smooth out any minor imperfections in the subfloor while slightly improving comfort and insulation. This type of underlay usually comes in the form of white foam.

Can underlayment be too thick?

Choosing a thick (10mm+) underlay for your stairs is not a good idea as it can pose a trip hazard. Moreover, thicker carpet underlays tend to compress slightly with heavy use, which can lead to irregular wear and unsightly lumps, particularly in frequently trodden areas.

How thick is typical underlayment?

Underlayment. Underneath the top flooring layer is often (though not always) an underlayment. It comprises padding materials and is typically about 1/4 to 1/2 inch in thickness. The purpose of the underlayment is to provide a sturdy yet comfortable layer for your outer flooring to sit on.

Does thick underlay make a room warmer?

Ball & Young supply underlay from 3mm all the way through to 11mm; the thicker the product, the more travel of compression there is, which makes the product feel more comfortable and gives better heat insulation.

Should I use 3mm or 5mm underlay for laminate flooring?

We would recommend an underlay of 3 – 5mm for laminate flooring. It should be at least 3mm thick to provide comfort and ground levelling properties. But, it should be no more than 5mm thick. If it's any thicker, you could experience problems with the laminate's locking system.

How thick is laminate flooring with underlay?

Typically, underlayment ranges from 2mm to 5mm in thickness. Therefore, a 6mm laminate floor installed with a 3mm underlayment would result in a final thickness of 9mm.

What is the recommended thickness for laminate flooring?

Often considered the sweet spot when it comes to laminate thickness, 10mm laminate offers durability, a good feel underfoot and low noise even in high-traffic spaces.

Do you overlap laminate underlay?

Each piece of underlay should be laid side by side, with the edges butting up against each other but without overlapping, as this can create an uneven surface for the laminate. Remember to tape the seams together with underlay tape to keep the pieces securely in place and prevent any moisture from seeping through.

Is 12mm underlay too thick?

For new flooring in a lounge, living space or bedroom, we typically recommend a carpet underlay at the top end of the thickness scale – around the 12mm mark. Such 'thick' underlays are regarded as the gold standard for domestic projects.

Does it matter which way you lay laminate underlay?

Once your floor is clean and dry, lay the laminate underlay along the lengths of the room – taking care to leave a gap of at least 10mm around any pipes. On concrete floors, lay the underlay with the vapour barrier side down. On wooden floors, lay the rubber side down first to prevent any unwanted movement.

What happens if you don t put underlayment under laminate flooring?

Without underlayment to add a layer between these damp subfloors and the surface flooring, your laminate can quickly become wet, warped, and mildewy, harming its overall integrity. Moisture over time can also break down floor adhesive which causes the floor to start warping.

Does laminate flooring underlay need expansion gap?

When laying laminate flooring it is essential that you leave at least a 10-12mm expansion gap around the perimeter of the floor. There are important reasons to do so, and we will cover them in this article. However, you won't need to worry about any spaces around the perimeter of your installation.

Can you put underlay on top of underlay?

While it might be tempting to leave an old layer of underlay in place and simply add a new one on top, this is not a good idea. Over time, old underlay can accumulate dirt, dust, and other debris, which can affect the hygiene and overall quality of your flooring.

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