What is Underlay?
Underlay is the material that sits between your subfloor and your flooring. Its purpose is to keep the floor stable, cushion noise from underfoot and even out any lumps and bumps, so your floor looks smooth and feels comfy when walked on.
Underlay also helps to insulate your floor, which makes it easier to keep your room warm and your heating bills down!
Jump to section:
Types of Underlay
Underlay can be made from several different types of material. We’ve broken down each option below:
-
Solid Wood
-
Engineered Wood
-
Laminate
-
LVT
Foam is an extremely affordable and versatile underlay material suited to solid wood, engineered wood and laminate flooring. It’s comfortable underfoot, absorbs sound and helps to keep your room cosy and warm.
Foam underlay pairs perfectly with underfloor heating too, so you can look forward to toasty toes, no matter the weather! Just make sure you check the TOG rating of your underlay to get the most out of your underfloor heating.
Please keep in mind that foam underlay doesn’t come with a damp proof membrane, so it’s not the best choice for a concrete subfloor.
-
Solid Wood
-
Engineered Wood
-
Laminate
-
LVT
Just like our foam underlay, our foam and foil underlay can be used with solid wood, engineered wood or laminate flooring.
Foam and foil underlay boasts all the benefits of foam underlay and also comes with foil backing which helps to retain heat. Not only does this keep your home warm for longer, but it might even reduce your energy bills!
Foam and foil underlay has a built-in damp proof membrane to protect your floor from damage caused by moisture building up underneath it.
-
Solid Wood
-
Engineered Wood
-
Laminate
-
LVT
Thermal underlay can be used with engineered wood, vinyl and laminate flooring, and it pairs perfectly with underfloor heating, thanks to its built-in insulation.
The thermal barrier helps to lock in heat, keeping your room warm for longer compared to non-thermal underlays. And the longer your room stays toasty the less you’ll need your central heating, so you could save energy too!
Thermal underlay also protects your floor from moisture, reducing the risk of damp under your floorboards.
-
Solid Wood
-
Engineered Wood
-
Laminate
-
LVT
If you’re looking for an underlay for wood or laminate flooring, fibreboard is a fantastic option. It’ll smooth any lumps and bumps, reduce footfall noise and insulate your room beautifully, keeping it cosy and warm.
You can loose-lay fibreboard underlay but we recommend securing the boards to each other using joint tape.
Make sure you lay a damp proof membrane (DPM) if you’re fitting fibreboard underlay over a concrete subfloor, as your floor could warp if moisture reaches it. And of course, never use fibreboard in your bathroom or wet room.
How Thick is Underlay?
Our underlay comes in a range of thicknesses from 1.8mm to 7mm so you can choose one to suit your needs. Different thicknesses of underlay offer different benefits. So, while you might think that the thicker your underlay is, the better, that’s not always the case.
There are several factors to consider when choosing your ideal thickness. Fitting underfloor heating with your new floor? Ask your flooring expert about the thickness of your underlay. You don’t want one that’s too thick as the warmth won’t rise through the floor effectively. And if you’ve chosen a click-fit floor, you’ll need an underlay that’s no more than 5mm thick, as the click system might not stay secure if there’s too much material under the planks.
What’s a Damp Proof Membrane?
A damp proof membrane (DPM) is a layer of material that’s laid between the subfloor and the flooring. This creates a barrier that stops damp from the subfloor reaching the floorboards.
Using a DPM is crucial if you’re using a floating method to install your floor over concrete. But if you have a different kind of subfloor - such as timber - you won’t need a DPM.
Our 3mm silver and 5mm gold underlays come with a built-in DPM, making them a great choice if your subfloor is concrete.
What happens if there’s damp under your floorboards?
Moisture can build up on the surface of your concrete subfloor and if you haven’t installed a damp proof membrane (DPM) it may reach your floorboards.
If the floorboards get wet, there’s a risk they’ll warp or shrink, which could affect the structure of your floor and make it unstable. This is why it’s important to use a damp proof membrane if you’re fitting your floor over concrete.
Which Underlay to Choose?
If you’re not sure what to look for in an underlay, then our guide below will walk you through all the different options available.
Handy hint
When you've decided on your underlay, check out our tips for prepping your subfloor and laying underlay.
Need a little help choosing the right underlay for your floor?
Simply request a callback and one of our friendly flooring experts will be in touch as soon as possible.