Types of Underlay
Which carpet underlay do I need? It can seem to be a bit of a minefield but actually it's quite straightforward, so here we go...
There are three main types of carpet underlays - sponge rubber, crumb rubber and PU foam.
Sponge rubber
This is the most widely used underlay in the UK and is made from synthetic rubber, usually constructed as a "waffle" which is filled with little bubbles of air or a “textured” flat which has a thick wall of spongy rubber. Sponge rubber underlay is really flexible and it's available in a very wide range of thicknesses and colours depending on your needs and budget. There are three primary grades of comfortable underlays: Luxury (premium comfort), General Domestic (very good everyday comfort) and Light Domestic (good comfort, usable around the home, but not recommended for stairs). You'll find a sponge rubber underlay in most British homes as they've been used for about fifty years. They are quite heavy (anything from 25 - 45kg for a roll) because they're made to support intensive foot traffic on the carpet. If you're worried about the weight then have a look at our PU foam underlays as they are much lighter.
Crumb rubber
Crumb rubber underlay has been around for about sixty years but it's having a bit of a renaissance recently as it's both incredibly hard wearing and recycled. Crumb rubber is made from recycled car tyres (approximately one recycled car tyre per square metre!) and, not surprisingly, it's as tough as......car tyres! This makes a crumb rubber underlay ideal for high traffic areas where the carpet is going to get a lot of punishment, such as halls, stairs and landings (especially if you've got young ones running up and down stairs); and rooms (normally dining rooms) where there is heavy furniture. Crumb rubber underlay has 100% recovery under heavy weights so it will recover from pressure marks and indentations - leaving your carpet looking as good as new. It's not as comfortable as sponge rubber but it feels good underfoot and will protect your carpet for many, many years.
PU foam
This underlay is made from recycled furniture foam and is both very comfortable and lighter in weight than rubber underlays. Most PU foam underlays are approximately 15-20kg for a roll. They have slightly better tog ratings than rubber and can be used all around the home, but they are a bit softer than rubber underlays. We would recommend crumb rubber as being more appropriate for heavy traffic areas and for working under heavy furniture.
For more carpet underlay advice see our sections on benefits of underlay or which underlay to use.
Helping the Environment
If you are looking for an environmentally friendly underlay then the very best is crumb rubber, which is made from recycled car tyres - you can read more about this type of underlay above.
A close alternative is PU foam underlay, which is manufactured from recycled furniture foam.
To do its job all underlay needs to be made from some form of springy or spongy material, so recycling those kind of materials into new underlay is a fantastic environmental solution.