LVT Underlay — Do You Need It? And What Are the Benefits?
There's one aspect of a luxury vinyl flooring installation that doesn't get nearly enough attention — the underlay. Choosing the right underlay, or choosing a floor that already includes it, has a significant impact on how your floor performs, feels, and sounds for years to come.
What is LVT Underlay?
LVT underlay is a layer of material placed between your subfloor and your luxury vinyl flooring. Its job is to bridge the gap between the two surfaces, improving the overall performance of the floor above it.
A good underlay does several things simultaneously. It absorbs impact from footsteps, reducing the noise that travels through the floor. It adds cushioning that makes the floor more comfortable to walk on. It helps smooth out very minor imperfections in the subfloor surface, giving the floor a more stable and even base to sit on. And it contributes to the thermal insulation of the room, helping to retain heat during colder months.
Do You Need Underlay for Vinyl Flooring?
Whether LVT flooring requires a separate underlay depends on the specific product. Some luxury vinyl floors come with underlay already integrated into the plank — others do not, requiring you to source and install a separate underlay layer before fitting the floor.
For floating click LVT and SPC floors, underlay is essential. Without it, the floor will feel hard and hollow underfoot, impact noise will transmit readily through the floor structure, and the lack of cushioning will place additional stress on the click joints over time. Skipping underlay — or using a low quality option — is a false economy that compromises both the performance and the lifespan of an otherwise good floor.
For glue-down LVT, the situation is different. Glue-down floors are adhered directly to the subfloor and generally should not be installed over a separate underlay, as this can compromise the bond.
What is IXPE Underlay?
IXPE stands for cross-linked polyethylene foam. It is a closed-cell foam material that has become the premium underlay choice for click LVT and SPC flooring installations.
Standard foam underlays — the kind sold cheaply in rolls at builders merchants — are open-cell foams. They compress relatively easily, and over time they break down under the repeated load of foot traffic. A floor that felt comfortable on day one can start to feel harder and sound noisier within a few years as the underlay beneath it compresses and loses its structure.
IXPE is fundamentally different. As a closed-cell foam, it is far more resistant to compression. It holds its thickness and shape under load, meaning the performance it offers on day one is maintained for the life of the floor.
The Benefits of IXPE Underlay
IXPE outperforms standard foam underlays across every meaningful measure. Here's what makes it the premium choice.
Acoustic performance — IXPE absorbs impact energy at the point of contact, significantly reducing the amount of sound that transmits through the floor structure. The result is a noticeably quieter floor, particularly beneficial in multi-storey homes and flats.
Comfort underfoot — IXPE provides a firm but forgiving feel that takes the edge off hard subfloors. It doesn't feel spongy or unstable, but the added give makes a noticeable difference to comfort, particularly on concrete subfloors.
Dimensional stability — IXPE's closed-cell structure resists compression and retains its thickness even under sustained load. The floor performs consistently across its entire surface for the duration of its life.
Thermal insulation — as an additional layer between the subfloor and the finished surface, IXPE helps slow the transfer of cold from concrete or stone subfloors, making the floor feel warmer underfoot and contributing to room heat retention.
Integrated vs Separate Underlay
When purchasing LVT or SPC flooring, you'll encounter two situations — either the floor includes underlay already attached to the back of the plank, or it doesn't and you'll need to buy it separately.
Integrated Underlay
Recommended
Attached to the plank at manufacture. Nothing extra to buy, no separate laying required, and compatibility is guaranteed.
Separate Underlay
Additional Cost
Must be sourced, delivered, and laid before fitting. Adds material cost and installation time to every project.
No Underlay
Not Recommended
False economy for click LVT. Hard, hollow feel underfoot and increased stress on click joints over time.
What to Look For When Comparing Underlay
If you're comparing flooring products and assessing the underlay specification, here are the key things to look for.
Material
IXPE is the premium choice. Standard PE foam is budget grade. IXPE's closed-cell structure means it lasts longer and performs better over the life of the floor.
Thickness
1.5mm is a solid specification for residential use. Thinner underlays offer less cushioning and reduced acoustic benefit.
Cell Structure
Closed-cell foam resists compression and lasts longer. Open-cell foam is cheaper but deteriorates faster under foot traffic, losing its thickness and performance within a few years.
Integration
Underlay attached to the plank at manufacture is more convenient, guarantees compatibility, and removes the need to purchase a separate product. Always factor in the cost of separate underlay when comparing prices.
The LVT Outlet Advantage
Every floor in the LVT Outlet range comes with 1.5mm IXPE underlay already integrated into the back of every plank. This isn't a budget add-on — it's a premium closed-cell IXPE foam that exceeds the standard underlay specification used by many competitors.
Nothing extra to buy — the underlay is included in the price of the floor, with no additional material to source or purchase.
Faster installation — with no separate underlay to lay, the fitting process is quicker and more straightforward from start to finish.
Guaranteed compatibility — the underlay is matched and tested specifically for the flooring product it's attached to, with no risk of voiding warranties.
Lower overall project cost — a floor with integrated IXPE underlay will almost always work out cheaper than a comparable floor sold without it once separate underlay is factored in.
The Bottom Line
For click LVT and SPC flooring, underlay is not optional — it directly affects how your floor feels, sounds, and performs over time. IXPE is the premium choice, and having it integrated as standard removes cost and complexity from your project. Every LVT Outlet floor includes 1.5mm IXPE underlay as standard, so you can fit straight from the box with nothing extra to buy.