Mattress Settlement and Body Impressions

One of the most common reasons for consumer telephone calls or emails to the National Bed Federation (NBF) is the question of settlement – or body impressions – forming on the surface of the mattress where the user lies.

This usually manifests itself within the first few weeks of use as the mattress fillings ‘mould’ to the user’s body shape, with the areas of most pressure (shoulders and hips) showing the greatest signs of settlement.

This can be particularly evident where mattresses use polyester fibre pads or multiple layers of synthetic fillings to create a ‘high-loft’ appearance. These fillings tend not to recover as well as more luxurious natural materials such as cashmere, mohair, horsehair, silk, wool, cotton etc.

There is no official industry standard for determining whether the settlement is excessive, as there are simply too many variables to consider. Some bed manufacturers, retailers and independent inspection companies use a measuring system based on the type of mattress fillings and the age of the product but this really isn’t based on any scientific evidence and so should only be used as a broad guideline.

Settlement on its own isn’t an indication that the mattress is failing – on the contrary, a mattress with generous layers of comfort fillings should be expected to demonstrate ‘body impressions’ and is an indication that the mattress is performing correctly. A mattress that has collapsed or sagged will be very evident when you lie on it – there will be a distinct lack of support, almost a sensation that you can feel right through to the bottom surface of the mattress.

Similar to a good pair of leather shoes, a new mattress will ‘relax’ and take on the shape of the user. There seems to be a misconception amongst some people that a mattress should look and feel as good as new even after months or years of service – despite it supporting your body for around seven to eight hours every night. Of course, this simply isn’t the case.

The extent to which the mattress will show signs of settlement depends on a number of factors such as the weight of the user, the number of fillings, the type of fillings, the firmness of the mattress, whether the mattress is two-sided or single-sided. Larger-size mattresses such as super king-size (180cm wide) and king-size (150cm wide) will show signs of settlement more so than a smaller-size mattress. This is because there is a wider area in the centre of the mattress that doesn’t get used and the fillings don’t become compacted. This ridge in the middle accentuates the sleeping areas on either side of it where the fillings will have settled or compacted during the night.

The NBF recommends that you follow the care instructions supplied with your mattress to prolong its life and minimise the effects of settlement.

In the absence of any specific mattress care instructions, don’t flip a one-sided, non-turn mattress – but always rotate it.  

One-sided mattress:

In the first three months rotate weekly and monthly thereafter.

Two-sided mattress: 

Week one: rotate  

Week two: turn/flip over 

Week three: rotate  

Week four: turn/flip over 

Repeat for three months and alternate rotating and flipping monthly thereafter. 

Some retailers offer a turning service if you can’t do it yourself. 

However, you should expect your mattress to show some signs of settlement and remember that it is not necessarily an indication that the mattress is failing.