Underlay 101

When you think of a floor, you probably think of the surfaces you walk on day in and day out. But this surface layer is just that – a surface layer, with many more layers hiding beneath it. These lower layers might not be visible, but they are incredibly important to ensure that your floor looks good, functions properly and stays put. One of those key layers is called underlay, and while rarely seen, it plays an important role in installing and enjoying your floor.

The Anatomy of a Floor

Before you can understand what underlay is and why you need it, you first need to understand how a floor works. As Shrek would put it, floors are like onions – they have layers, and each plays an important role in providing a secure and comfortable surface to walk on. So, we’ve broken it down into its component parts, staring at the top and working down, to give you an idea of how it all fits together.

  • Floor Covering: This is the final, visible flooring surface – the hardwood planks, carpeting, ceramic, tile or vinyl. In other words, this is the bit that you will see and walk on.
  • Underlay: Just underneath the floor covering sits a layer of material. It’s usually only around a quarter to half an inch thick, and it’s designed to provide a smooth, flat surface for the floor covering to sit on, as well as some insulation for the floor itself and a barrier between the floor coverings and the subfloor. Underlay can be made of a lot of different materials, from plywood to cement, rubber and even foam padding. The type of underlay used will likely depend on the condition of the subfloor, the type of floor covering being used and the purpose of the room.
  • Subfloor: Beneath the underlay is your subfloor, and this is the layer of OSB or plywood that was part of your home’s construction. In other words, it’s what makes a floor, a floor. These panels of OSB or plywood are integral to the structure of your home, and provide the strength and rigidity you need to be able to walk on your floor. These will already be in place when the underlay and floor covering is installed.
  • Joists: These are lateral wooden frames that rest on the foundation walls of your home, providing structural support for the entire floor. Joists are typically made from 2-by-10 or 2-by-12 lumber or engineered microlam members, depending on what the builders of your home choose.

Why Do You Need Underlay?

So, now you know what underlay is and where it fits into the anatomy of your floor, it’s time to look at why you need it. Unlike the lower layers of the floor, underlay is a catch-all term that can mean many different types of material. But whatever the type of underlay you choose; the purpose is always the same. There are 3 key functions underlay serves within your floor, which are:

  • To Provide A Smooth Surface: No one wants a wobbly floor. To make sure your floor covering ends up as smooth and level as possible, underlay is needed to smooth out any bumps, dips or irregularities that might be in your subfloor. This provides installers with a more predictable surface for installation, and a much better finished product at the end.
  • Improves Adhesion: Underfloor also helps your floor covering of choice stick better. Good bonding between the subfloor and the floor covering is important, as it stops your floor covering moving around when walked on, or shifting over time to become uneven. And since subfloors are known to expand and contract, this can cause problems later down the line.  Underfloor provides better grip and allows for that expansion, so you never notice a difference in your floor.
  • Improves Stability: As a side effect, underlay can also give the entire floor better structural stability. This is particularly useful in older homes, where subfloors tend to be constructed from boards rather than OSB or plywood sheets, and aren’t as stable.

When it comes to underlay, you have a lot of options available to you. But it can be difficult to know what to choose, especially if you don’t know much about the core construction of your home At Warson Flooring, we care about every element of your flooring experience, which is why our expert fitters can assess, advise and fit all types of underlay alongside your floor coverings. With the right underlay, you can be sure your floor will look amazing, and stay that way for much longer. If you would like to know more, just drop us an email, and one of our fitters will be in touch as soon as possible.

Chat to us today