What do you put under vinyl flooring?
Have you just bought vinyl flooring to install in your home? Or are you trying to find out how easy it will be before committing?
If so, you’ll be happy to know that vinyl flooring is a great choice for any home, and there are quite a few underlay options you can choose from! However, the right choice ultimately depends on your subfloor, the room in which you’re installing it, and the type of underfloor feel you’re aiming for.
With so many choices, whittling it down to one can prove challenging; Mersey Flooring is here to make the decision easier. We’ve compiled a list of the best underlays for vinyl below, along with guidance on when to choose each one.
Types of subfloors and suitable underlay
When selecting underlay for your vinyl, it mainly comes down to the type of subfloor on which you’re installing it.
Let’s take a closer look at the most common subfloor types found in UK homes and commercial properties.
Concrete
Concrete is the most common type of subfloor you’ll find in most UK buildings.
The reason for this is its strength and durability; it remains sturdy even in challenging conditions and provides a stable base for flooring to be installed onto. However, one issue that comes up is its moisture resistance.
Even if the surface feels dry, concrete can still release moisture into your flooring over time. So, here are our underlay suggestions:
- Moisture-resistant foam underlay: Look for foam underlays with a built-in damp proof membrane (DPM), as this creates a barrier to stop damp from rising.
- Cork underlay: With great moisture resistance and acoustic insulation, cork is great for rooms with fluctuating moisture levels.
- Combination underlay (thermal + moisture protection): Opt for combination underlays, such as ThermoGuard Vinyl Underlay, to combat heat loss. It offers excellent insulation and moisture control.
Tip: Before laying underlay on concrete, use a self-levelling compound to make sure the subfloor is flat with no dips. Never skip a damp proof membrane, as this is what adds years to your vinyl flooring.
For more information on selecting a vinyl underlay for your concrete floor, visit our blog.
Plywood
Plywood floors serve as a great subfloor for vinyl; they’re smooth, flat, and stable. However, if you’re installing a thinner vinyl, imperfections from the plywood can show through quite easily.
For this reason, it’s best to level any imperfections in the subfloor before installing vinyl. Plywood floors are mostly found in the upper levels of buildings or timber-framed properties.
When laying vinyl on plywood, we suggest these underlay materials:
- High-density foam underlay: With its soft cushioning and minimal compression, high-density foam underlay provides a smooth finish for your vinyl.
- Acoustic felt underlay: If you’re looking for excellent sound absorption, acoustic felt is an ideal choice. Beneficial for upper floors and flats, this blocks sound transmission from lower floors for a more peaceful environment.
Tip: If your plywood boards are old or uneven, use a liquid levelling agent to smooth them out, or add a 6mm plywood overlay before applying the underlay.
Screed
Screed subfloors are made from cement, water, and sharp sand, providing a smooth and stable surface.
You’ll often find this in new builds, extensions, or conservatories, as it uplifts the appearance of concrete floors. Screed can be a challenging subfloor to work with due to cracking, expansion and contraction, as well as poor moisture retention.
For this reason, choosing the right subfloor is vital:
- Moisture-resistant foam underlay with DPM: Selecting a moisture-resistant foam underlay and a damp proof membrane can help prevent trapped moisture. The foam also provides a soft, underfoot feel.
- Cork underlay: Naturally breathable and soundproof, cork is ideal for properties where moisture isn’t an ongoing issue. It also offers excellent thermal insulation and is an eco-friendly option.
- Rubber underlay: Ideal for high-traffic areas, rubber underlay offers excellent impact resistance, making it perfect for busy households. It can handle minor imperfections in the screed without excessive compression and provides acoustic insulation.
Tip: Before installing underlay, make sure the screed subfloor is free from visible cracks and is completely dry. Use a flexible filler or smoothing compound to address any imperfections.
Timber
Do you have a timber subfloor? These are found in more traditional homes, such as Victorian terraces or older townhouses.
While they may look attractive, timber subfloors can cause numerous issues when installing vinyl. They’re prone to slight movement, seasonal shrinkage, and uneven surfaces. Timber floors can also create creaking sounds when walked on due to poor sound insulation.
Here’s a range of underlay options suitable for timber floors:
- Rubber underlay: Providing durability and acoustic control, rubber offers noise reduction when installing vinyl flooring. It’s also strong enough to cope with minor subfloor imperfections.
- Felt underlay: Felt is a great option for bedrooms and flats, as it provides a soft, underfoot feel and natural soundproofing. This is especially beneficial for thinner vinyl flooring.
- Foam underlay: More suited for light, domestic use, foam underlay provides basic cushioning and conceals minor subfloor imperfections. However, it’s less effective for high-traffic areas.
Tip: Overlay your timber subfloor with 6 mm–12 mm plywood sheets before placing the underlay down. By doing so, you’ll end up with a flat, stable surface, preventing timber movement on the surface floor.
Factors to consider when choosing underlayment
When selecting an underlay for your vinyl, several key factors should be considered and incorporated into your decision.
If you get it right the first time, you’ll avoid costly repairs later on.
1. Moisture protection
Moisture is one of the biggest causes of damaged vinyl. Before laying down your vinyl floors, you need to add a moisture barrier (especially with concrete and screed).
A Class I moisture barrier is suitable for concrete. If possible, look for underlay with built-in DPM or moisture resistance.
2. Noise reduction
If you’re installing vinyl in a kitchen or living room on the bottom floor, then noise reduction might not be the biggest concern.
However, an underlay that offers excellent sound insulation is beneficial for bedrooms or flats, where noise can travel easily. Semi-detached or terraced houses can also benefit greatly from acoustic underlay.
3. Thermal insulation
Are you adding vinyl flooring to a conservatory or extension? These rooms are more prone to fluctuating temperatures, as they typically have cold foundations and lots of glazing.
Thermal underlay can help trap heat, reducing draughts, heat loss, and energy bills.
4. Comfort underfoot
A soft floor may not be of the highest importance for areas like bathrooms and kitchens.
However, bedrooms, nurseries, and playrooms can benefit from a softer vinyl flooring where children are likely to play. This adds comfort, reduces the chance of hard falls, and brings a cosy touch to your home.
Expert tips for installing underlay
- Always allow the underlay and vinyl to acclimate to the room temperature for 24 hours before installation.
- Remove any dirt and debris from the subfloor before laying down the underlay.
- Make sure there are no sharp edges or lumps when installing underlay on concrete or screed.
- Always lay the underlay with the smooth side up (unless instructed otherwise).
- Avoid cutting the underlay into smaller sheets or overlapping them—longer sheets minimise joints and visible lines.
- Use underlay joining tape to secure seams when installing floating vinyl floors (click systems).
- Avoid installing vinyl over existing laminate or vinyl floors, as this can reduce their lifespan and cause moisture issues.
Why choose Mersey Flooring?
Are you looking for vinyl that’ll live up to its lifespan? At Mersey Flooring, we offer a range of beautiful vinyl floors that can uplift any kitchen, living room, bedroom, or bathroom.
With a choice of various styles, colours, and finishes, our vinyl flooring is cost-effective, easy to install, and durable.
With the right underlay, you can enjoy your vinyl floors for years to come! So, what are you waiting for? Browse your new flooring today.