Laminate flooring is a popular choice thanks to its durability, cost-effectiveness and wide range of styles. One of the most common questions is whether underlay is actually needed. In short: yes, we would always recommend using underlay with laminate flooring. In fact, it’s rare to find a laminate manufacturer that does not recommend it as part of the installation.
There are a few products on the market with built-in backing, but these are often not true laminate. Many are actually SPC flooring (sometimes referred to as “plastic laminate”), which is a different product altogether. It’s worth understanding that distinction before deciding to skip underlay.
What Does Underlay Do?
Underlay sits between your subfloor and the laminate boards, and it plays a key role in how your floor performs day to day.
- Noise reduction: One of the biggest benefits is sound control. Without underlay, laminate can sound hollow and noisy underfoot. Using the wrong underlay can also create excess noise, so choosing the correct type is important.
- Comfort underfoot: Underlay adds a slight cushion, making the floor feel less rigid and more comfortable to walk on.
- Moisture protection: On concrete subfloors especially, underlay with a damp proof membrane helps prevent moisture from damaging the laminate.
- Improved stability: It helps create a more even surface, reducing movement and improving the lifespan of the floor.
- Thermal performance: Some underlays provide light insulation, helping retain heat in the room.
For additional technical guidance, organisations like BSI Group and European Producers of Laminate Flooring outline best practices around laminate installation and subfloor preparation.
Why Underlay Is Almost Always Required
In real-world installations, underlay is not optional in most cases.
- Concrete subfloors: You need a moisture barrier. Without it, you risk swelling or damage over time.
- Timber subfloors: Underlay helps reduce movement and noise, especially between floors.
- Upstairs rooms or flats: Sound transfer is a big issue. The right acoustic underlay makes a noticeable difference.
- Underfloor heating: You’ll need a compatible underlay designed to allow heat transfer without trapping it.
Even where products claim to have “built-in underlay”, always check the specification carefully. If it’s true laminate, additional underlay is almost always still recommended.
A Quick Note on “Laminate with Built-In Underlay”
This is where confusion often happens. Some products marketed this way are actually SPC flooring, not laminate. SPC (stone plastic composite) has a rigid core and often includes an attached backing layer. If you’re considering this type of product, it’s worth reading more about it in our SPC flooring guide (internal link here).
Types of Underlay
Choosing the right underlay matters just as much as choosing the flooring itself.
- Foam underlay: Standard option. Good for basic installs and light noise reduction.
- Moisture barrier underlay: Essential for concrete floors.
- Acoustic underlay: Best for upstairs rooms or flats where noise control is important.
- Thermal underlay: Designed to improve insulation or work with underfloor heating.
- Fibre or felt underlay: Denser option, often better for sound reduction and stability.
The key is matching the underlay to the environment and the laminate specification.
Installation Basics
A good installation starts before the boards go down.
- Make sure the subfloor is clean, dry and level
- Lay underlay edge to edge, without overlapping unless specified
- Tape joints where required
- Leave expansion gaps around the perimeter (usually 10–15mm)
- Follow the laminate manufacturer’s instructions throughout
If you’re using underfloor heating, always check both the laminate and underlay are approved for it.
Common Mistakes to Avoid
- Skipping underlay altogether: This usually leads to noise, movement and reduced lifespan.
- Using the wrong underlay: Too thin, too thick or the wrong type can all cause issues, especially noise.
- Ignoring moisture: A common cause of laminate failure on concrete floors.
- Assuming built-in backing is enough: Often it isn’t, especially if the product isn’t true laminate.
Final Thoughts
Laminate flooring should almost always be installed with underlay. It improves comfort, reduces noise and protects the floor long term.
Just as important as using underlay is choosing the right type. The wrong choice can lead to a noisy, unstable floor, which is one of the most common complaints with laminate installations.
If you’re unsure, always follow the manufacturer’s guidance or speak to a flooring specialist before installing. It’s a small investment that makes a big difference to how your floor performs.