Rug Underlays: The Layer Nobody Sees

Of everything we sell, the rug underlay is the least glamorous and among the most important. Nobody admires an underlay. But almost everyone notices the difference it makes, even if they cannot quite say why a rug feels so much more settled, comfortable and secure.

Four things an underlay does

1. It keeps the rug in place. On timber, stone, tile or vinyl, a rug without grip will slide, ruck and creep. That is not just irritating; it is a trip hazard, particularly on stairs, in hallways and in homes with young children or older relatives. A good underlay anchors the rug firmly.

2. It adds comfort. A thin flatweave or low-pile rug can feel surprisingly hard over a solid floor. Underlay adds a layer of cushioning that makes the rug feel more luxurious underfoot.

3. It protects the rug. Every footstep grinds the back of a rug against the floor beneath. Over time, that friction wears the foundation. Underlay acts as a buffer, absorbing impact and reducing wear, which helps a good rug last considerably longer.

4. It protects the floor. The rough backing of some rugs can scuff delicate finishes. An underlay sits between the two, keeping your floor in better condition.

Rugs on carpet

If you are laying a rug over fitted carpet, you may have noticed it slowly travel across the room or form ripples. This is called creep, and it is caused by the movement of the carpet pile beneath. A dedicated rug-to-carpet underlay helps hold it still. We explore this in our guide to layering a rug over fitted carpet.

How to size an underlay

An underlay should be slightly smaller than the rug, by a few centimetres on each side, so that it is completely hidden and the rug's edges lie flat to the floor rather than perching on a visible lip. Most underlays can be trimmed with sharp scissors for a precise fit. Our Snug Rug underlay is available in standard sizes to suit the most popular rug dimensions.

A few cautions

• Underfloor heating: check that your underlay is suitable for use with underfloor heating, as some materials insulate more than others. Our guide to rugs and underfloor heating explains why this matters.
• Delicate floor finishes: if you have an unusual or newly applied finish, test the underlay in a hidden corner first.
• Keep it clean: lift the rug and underlay occasionally to vacuum the floor beneath. Grit trapped underneath will wear both.

Curling corners and new rugs

An underlay also helps a new rug relax and settle. If your rug arrives with a little curl at the corners from being rolled, underlay combined with the techniques in our guide to flattening a new rug will usually solve the problem within days.

A decorator's note

When budgeting for a rug, include the underlay from the start. It is a modest addition to the cost, and it is the difference between a rug that merely sits on the floor and one that feels properly part of the room.