The choice of carpet tile backing is a key factor when it comes to the durability of your flooring. Backing type also affects the underfoot comfort and acoustic capabilities, making it a really important decision when choosing flooring. That said it can be difficult to find relevant information on the different types of carpet backing available and it’s often a struggle to decipher the scientific jargon. This blog simplifies and explains the options so you can be sure you choose the right backing for your next project.
When it comes to choosing commercial carpet tiles you have a whole range of options to choose from: different patterns, fibre types and face weights. As well as the aesthetic choices, there’s also are several different backing options to consider.
There are three main types of carpet tile backing:
- Hardback
- Open cell cushion backing
- Textile Felt backing
Each type of backing affects the floorings acoustic properties, underfoot comfort and durability differently.
What’s the difference between carpet tile backing options?
Hardback
Hardbackings are typically made of filled bitumen compounds or filled polyolefins. The hardbacking gives the tile stability on the floor but offers no additional benefits. As the backing material doesn’t compress under footfall, it means the carpet fibres directly absorb the impact, causing visible wear and appearance degradation or “traffic lanes” more quickly than would occur with cushion and felt alternatives.
The dense non-porous nature of hardback backing provides minimal acoustic benefit. It limits sound energy from dissipating into or through the backing, instead reflecting the sound back into the space. Hardback tiles are less effective at reducing both impact noise and reverberation when compared to felt-backed and cushion-backed systems.
Felt
Felt is a textile backing system made of mechanically entangled fibres, designed to trap air within the backing. The fibres are typically from recycled materials such as rPET from recycled drinks bottles, so felts can be a low environmental impact option, however longterm performance can be an issue. Initially, when subjected to footfall the trapped air compresses, absorbing impact energy, protecting the carpets fibres from wear, and providing sound absorbing properties, contributing to reduced impact noise and lower reverberation.
However, over time the felt structure compresses, causing the tiles to lose thickness, and some of its wear absorbing properties. Since a materials acoustic performance is directly related to its material thickness, consequently felt-backed tiles may not retain their original sound performance throughout their entire lifespan. Similarly, as compressibility is reduced the carpet fibres begin to directly absorb more of the footfall impact, leading to visible wear. In high-traffic areas, this collapse occurs more rapidly, resulting in uneven tile thickness across the floor. In environments requiring frequent underfloor access, tiles may be lifted and reinstalled; if not returned to their original locations, the thickness variation can create an uneven floor, highlight seams, and result in an uneven, poor-quality finish across the floorplane.
Open cell cushion
Open cell cushion backing is manufactured using recycled polyurethane and features an interconnected network of resilient air pockets and channels. During the recycling process, secondary polyurethane is compressed, producing a denser more robust material than virgin polyurethane, ideal for withstanding the tough demands of flooring. The open cell cushion compresses under footfall to absorb impact energy and then recovers post-compression, effectively protecting carpet fibres and maintaining performance over time. Incorporating 90% recycled polyurethane not only reduces the environmental impact but also improves durability of the flooring. Open cell cushion backing has proven track record, with over two decades of in-market performance since it was first launched, demonstrating long-term resilience, sustained acoustic performance and consistent comfort and ergonomics throughout its lifespan. As the most premium backing option in the market, it offers the highest level of sound absorption and the greatest underfoot comfort.
The myths of carpet tile backings
Myth: Felt performs the same as cushion backing
While felt backing may initially provide some of the same performance benefits as cushion backing, they are not retained over the product’s entire lifespan. Over time the felt’s structure can collapse (known as poor Dynamic and Static Compression recovery) reducing the thickness and therefore some of its sound absorption and durability.
MYTH: using a separate cushioned underlay with hardbacking saves money and delivers the same benefits as cushion backing
Hardback tiles tend to be cheaper than cushion-backed tiles but having a separate cushioned underlay increases both installation cost and time due to the additional materials, labour and coordination required for two separate flooring layers rather than one integrated system. It also complicates underfloor access; both the tile and underlay have to be uplifted, increasing maintenance time, disruption and the risk of damage over repeated uplifting. In addition, misalignment or compression difference between the tile and underlay can cause uneven seams and a result in a poorer overall aesthetic compared to tiles with built-in cushion backing.
MYTH: The Polyurethane in cushion backing is harmful to human health
While liquid polyurethanes (such as insulation foams and varnishes) can cause off-gassing which can be damaging to human health, pre-formed polyurethane is already fully reacted and off-gassed. It is not harmful and is used in many everyday products, from furnishings, to automotive interiors and most notably in athletic footwear such as Nike trainers – where it’s valued for it’s durability and comfort. The same qualities are what make it excellent for carpet tile backing. Milliken’s cushion backing is made of 90% recycled polyurethane, combined with 10% virgin polyurethane that acts as a binding agent. This is fully reacted prior to incorporation into the carpet tile composite, enabling Milliken carpet tiles to meet rigorous air quality performance tests to ensure low VOC emissions and provide peace of mind.
Myth: Open Cell Cushion Backing Absorbs Moisture, Promoting Growth of Mould and Mildew
The structure of open cell cushion backing promotes moisture wicking and not water retention. This means its interconnected structure allows any moisture vapour present in the subfloor to migrate through the backing and evaporate at the seams between the tiles, rather than pooling as water beneath them. Hard backings are impermeable and so moisture from damp sub-floors can become trapped as liquid. This trapped moisture is what can promote mould and mildew growth.
Therefore it is preferable to have tiles with a breathable open cell polyurethane or felt backing vs a hard backing that’s impermeable to moisture in areas where damp subfloor such as newly laid concrete can be a concern.
FAQs
What are the main types of carpet tile backing?
There are three main types: Hardback, Cushion, and Textile Felt Backing. Each offers different levels of durability, comfort, and acoustic performance.
Which backing provides the best underfoot comfort and sound absorption?
Open Cell Cushion Backing is the premium option. It offers the highest level of sound absorption and the greatest underfoot comfort, thanks to its resilient air pockets and long-term performance.
Is felt backing as good as cushion backing?
No. Felt backing may initially provide similar benefits, but over time it compresses and loses thickness, reducing its acoustic and durability performance.
Can I use a separate cushioned underlay with hardback tiles to save money?
It’s not recommended. Using a separate underlay increases installation cost and time, complicates underfloor access, and can lead to uneven seams compared to integrated cushion backing.
Is polyurethane in cushion backing harmful?
The polyurethane in carpet tile cushion backing is already completely off-gassed and meets rigorous air quality standards ensuring it is not harmful to human health.
Does open cell cushion backing absorb moisture and cause mould?
No. Its structure promotes moisture wicking and evaporation, reducing the risk of mould compared to impermeable hardback tiles.
