Flooring Underlay Explained: The Complete Guide
Choosing the right underlay is one of the simplest ways to improve the performance, comfort, and longevity of your new floor. Whether you’re installing laminate, LVT, or engineered wood, the underlay you select plays a huge role in how the finished floor feels, sounds, and wears over time. This guide by Floor Land breaks down what underlay actually does, the different types available, and how to choose the best option for your home.
What Underlay Does
Sound Reduction
Underlay helps absorb impact noise—think footsteps, dropped items, or the general echo you get in hard‑floored rooms. A good acoustic underlay can dramatically reduce sound transfer between floors, making it ideal for flats, upstairs rooms, and busy family homes.
Moisture Protection
Many modern floors, especially laminate and engineered wood, need protection from rising moisture. Underlays with built‑in damp‑proof membranes (DPMs) create a barrier between the subfloor and your new flooring, preventing warping, swelling, and long‑term damage.
Comfort
Underlay adds a layer of cushioning that improves underfoot comfort. It can make laminate feel softer, reduce fatigue in high‑traffic areas, and even help with thermal insulation—keeping rooms warmer and more energy‑efficient.
Underlay Types
Laminate Underlay
Laminate floors benefit from lightweight, flexible underlays that provide cushioning and stability. Popular choices include:
- Foam underlay – Affordable and easy to install, ideal for most rooms.
- Foil‑backed underlay – Adds thermal insulation and moisture protection.
- Acoustic laminate underlay – Reduces noise transfer, perfect for upstairs rooms.
Laminate is sensitive to moisture, so pairing it with an underlay that includes a DPM is often recommended unless your subfloor already has one.
LVT Underlay
Luxury Vinyl Tile (LVT) requires a denser, more stable underlay because the planks or tiles are thinner and more flexible than laminate or wood. The right LVT underlay:
- Levels out minor subfloor imperfections
- Reduces sound
- Provides comfort without compromising stability
Brands like Quick‑Step offer dedicated LVT underlays designed to work with their click systems, ensuring a secure fit and long‑lasting performance. Many ranges of LVT will now come with underlay already attached to the planks, so be sure to check if purchasing underlay separately is necessary for the LVT you are interested in.
Engineered Wood Underlay
Engineered wood floors need an underlay that balances cushioning with firm support. Too much softness can cause movement, while too little can reduce comfort. Common options include:
- Fibreboard underlay – Excellent for levelling uneven subfloors.
- Rubber underlay – Durable, dense, and great for sound reduction.
- Foam with DPM – Lightweight and moisture‑resistant.
Because engineered wood is more stable than solid wood, it pairs well with a wide range of underlays, but moisture protection is essential on concrete subfloors.
Acoustic Underlay
If noise reduction is a priority, acoustic underlay is the way to go. These underlays are typically made from rubber, cork, or high‑density foam and are designed to absorb both impact and airborne sound. They’re ideal for:
- Apartments
- Bedrooms
- Home offices
- Upper‑floor installations
Acoustic underlays can be used with laminate, engineered wood, and some LVT systems, depending on manufacturer guidelines.
Damp‑Proof Membrane Underlay
A DPM underlay includes a built‑in moisture barrier, making it essential for installations over concrete or in rooms where humidity levels fluctuate. These underlays:
- Prevent moisture from reaching the floor
- Protect against warping and swelling
- Are often combined with insulation or acoustic layers
If your subfloor is concrete and less than two months old, or if you’re unsure about moisture levels, a DPM underlay is a smart investment.
How to Choose the Right Underlay
Room Type
Different rooms have different demands:
- Living rooms & bedrooms – Comfort and sound reduction are key.
- Kitchens & hallways – Durability and moisture protection matter most.
- Flats & upstairs rooms – Acoustic underlay helps reduce noise transfer.
- Conservatories – Look for thermally stable underlays designed for temperature fluctuations.
Subfloor
Your subfloor determines which underlays are suitable:
- Concrete – Needs moisture protection; DPM underlay is often essential.
- Floorboards – Benefit from acoustic underlay to reduce creaking and sound transfer.
- Slightly uneven floors – Fibreboard or high‑density underlay can help level the surface.
Budget
Underlay ranges from budget‑friendly foam to premium acoustic or rubber options. While it’s tempting to save money here, underlay is one of the most cost‑effective upgrades you can make to improve your floor’s performance. Spending a little more can deliver:
- Better sound insulation
- Longer floor lifespan
- Improved comfort
- Enhanced stability
Installation Tips
- Check manufacturer guidelines – Some flooring brands, like Quick‑Step, specify which underlays are compatible with their products.
- Prepare the subfloor – Clean, dry, and level surfaces ensure the best results.
- Lay the underlay in the correct direction – Typically perpendicular to the direction of the floor planks.
- Tape the seams – Prevents movement and ensures a continuous moisture barrier.
- Avoid overlapping – Underlay should sit flush without bunching or doubling up.
- Allow expansion gaps – Both the flooring and underlay need space around the perimeter.
Authored by Lee McCarthy.
Floor Land
Cockhedge Shopping Centre
Warrington
Cheshire
United Kingdom
WA1 2QQ
