How long does carpet underlay last?
You want to know whether underlay wears out and when it needs replacing.
Underlay generally lasts about as long as the carpet on top of it, and it is normally replaced whenever the carpet is. Over years of foot traffic it compresses, crumbles or flattens, especially in walkways, and a worn underlay makes a new carpet wear faster and feel harder. Reusing it saves a little now but usually costs you carpet life later.
Written for: For anyone replacing carpet and deciding whether the old underlay can stay.
What happens to underlay over time
Underlay works by springing back after each footstep. Foam and rubber gradually lose that spring. Older rubber crumb and waffle rubber underlays can break down into dust, and foam flattens in lines that follow the way people walk. Once it has lost its bounce, it stops supporting the carpet backing, and the carpet pile then crushes more quickly.
Signs your underlay has had it
You can often tell before lifting anything: the carpet feels hard or uneven in the main walkways, it rucks despite being stretched, or there are dips where furniture used to sit. When the old carpet comes up, the evidence is obvious.
- Crumbling or powdery rubber under the carpet
- Flattened tracks through doorways and along corridors
- Damp, staining or a musty smell
- Tears or gaps where joints have separated
Why fitters replace it with new carpet
A new carpet laid on tired underlay takes on its shape. Tracks and dips show through, and the carpet is doing the work the underlay should do. Most carpet manufacturers and fitters expect new underlay with a new carpet, and it is generally a small part of the total cost compared with the carpet itself.
Where it wears fastest
Stairs take the hardest wear, because every tread nose is loaded with each step. Hallways and the path from the door to the sofa follow. Bedrooms usually keep their underlay in reasonable condition for longest, which is also why bedroom carpets tend to outlast those on stairs.
Choosing the replacement
Underlay is stocked at both of our Kent warehouses alongside the carpet, so both can be bought and priced together. If fitting is arranged through us, underlay is part of the itemised quote so you can see what is being laid.
Looking after underlay so it lasts
Underlay cannot be cleaned or seen once fitted, but you can help it. Deal with spills quickly so liquid does not soak through the carpet into the underlay, where it can smell or stain. Use furniture cups under heavy pieces, move large furniture occasionally, and put a mat inside external doors to cut down the grit that grinds into both layers. In rooms prone to damp, fixing the damp first is essential, because no underlay survives long on a wet floor. When the time comes to change carpet, lifting the old underlay also lets the fitter check the floor beneath for problems that were hidden before.
Still wondering?
- Can I put new carpet on old underlay?
- You can, but it is not recommended. Worn underlay shortens the life of the new carpet and lets old dips show through.
- Does underlay last longer than carpet?
- Rarely by much. It is usually replaced at the same time as the carpet.
- Is rubber or foam underlay longer lasting?
- Both can last well if good quality. Density and the traffic in the room matter more than the material alone.
- Should stairs have new underlay each time?
- Yes. Stair underlay is under the most stress, so replacing it with the carpet is especially worthwhile.
- Where can I buy underlay in Kent?
- Both the Maidstone and Gillingham warehouses stock underlay alongside their carpet.