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Tips on how to fix a sagging mattress

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A mattress that is lumpy, out of shape or showing visible permanent sagging will not improve over time and will need to be replaced. But in the meantime, turning your mattress or replacing your bed base may help.

Over time, mattresses can start to sag and feel uncomfortable. This is usually a sign of general wear and tear. A sagging mattress can put your body out of natural alignment. This causes the spine to bow downwards and can put uneven pressure on the hips and lower back.

A sagging mattress will not support your spine correctly. It can often make you feel that you’re sinking to the bottom of the mattress, making it harder to turn over in bed.

A mattress that is lumpy, out of shape or showing visible permanent sagging will not improve over time and will need to be replaced. But in the meantime, there may be some things you can do to prevent it from getting worse until you buy a new one.

mattress sagging in the middle

Turn your mattress

Regular mattress turning, especially during the first few weeks or months of use, will allow the fillings in the mattress to settle more evenly. This will reduce the effects of sagging. To ensure you turn the mattress correctly, refer to the manufacturer’s care advice.

‘Non-turn’ mattresses have fillings on the top side only. As there is only one sleeping side, you can only rotate these mattresses from head to toe. Double-sided mattresses can be rotated and flipped over to ensure even wear on both sides.

Replace your bed base

If your mattress is in reasonably good condition, your bed base could be causing the problem. An old worn-out bed base is unlikely to support the mattress. If the bed base is sagging or has collapsed, the mattress will quickly take its shape.

Similarly, if your mattress sits on top of a slatted bed frame, it may sag between the slats if they are too far apart. Each manufacturer provides guidance on slat spacing. Generally, the slats should be no more than 7.5 cm apart.

If you decide to replace your old bed base, it’s important to ensure that the new base is compatible with your mattress. Some mattresses work best on solid bed bases, and you will also need to ensure that the bed base is strong and sturdy enough to support the weight of the mattress.

Can mattress topper fix a sagging mattress?

A mattress topper is an extra cushioning layer that rests on your mattress. A topper is unlikely to improve an old, unsupportive mattress. It will simply conform to its shape, dipping in the same areas where hollows and indentations are prominent on the mattress’s sleeping surface.

What causes a mattress to sag?

You will often experience discomfort and poor quality sleep with a sagging mattress. You may wake up feeling sore with aches and pains.

The fillings in a mattress will naturally flatten over time. Indentations and body impressions can start to appear on the surface of the mattress with use. This is particularly evident in the areas where most of the sleeper’s weight is concentrated, such as the shoulders and hips.

This is often described as mattress settlement and is usually no cause for concern. A mattress should contour to the shape of the body. Indentations and body impressions are evidence that the mattress is performing as expected. Mattress settlement can be more prominent in larger size mattresses like king size and super king size due to the wider sleeping area. Regular mattress turning will help ease the problem.

But over time, the components in the mattress can start to break down and cause the mattress to sag under the pressure from the sleeper’s body weight. The heavier the user, the more stress and strain is put on the mattress. This is evident when two people share a mattress of widely differing body weight and size. Sagging tends to be more noticeable on the heavier person’s sleeping side.

Cheaper mattresses often contain synthetic fillings like polyester. These fillings are not as durable as natural materials like wool and horsehair. They tend not to recover as well over time.

Similarly, one-sided mattresses tend to sag quicker than double-sided mattresses as the sleeper’s body weight is concentrated on the same area. In contrast, double-sided mattresses can be flipped over to evenly distribute the sleeper’s body weight on both sleeping sides and allow the fillings to settle more evenly.

Also, if the mattress gets damp or wet from moisture, liquids or neglect, this can damage its components, leading to premature sagging. Furthermore, a damp mattress provides the ideal conditions for mould and mildew to thrive.

A good quality mattress protector can help protect your mattress against stains, spillages and accidents. This will help keep it clean and dry and extend its life.

Can you complain about a sagging mattress?

Mattress sagging is generally caused by normal wear and tear and is not usually covered by a manufacturer’s guarantee or warranty.

In some cases, premature or excess sagging may be due to faulty materials or poor workmanship.

If you are not satisfied with the quality of your mattress during the warranty or guarantee period, contact the store from whom the mattress was purchased.

Providing you have followed the manufacturer’s care advice, the store will typically arrange to inspect the mattress. There is no industry standard for excessive sagging as there are too many variables to consider. But some stores may work on an acceptable tolerance level.

If the sagging is deemed to be the result of a product defect, they will usually arrange to repair or replace the mattress as appropriate.

Final thoughts

A sagging mattress is one of the most common reasons for customer complaints. But although mattresses are built to withstand excessive use, they will not last forever.

Mattress sagging is inevitable, but correct care can minimise its effects. But when an old unsupportive mattress is sagging, it’s unlikely to improve. Any measures put in place are only likely to be temporary, and the best course of action is to invest in a new mattress.

About the author

About the author

Tony Brown is the founder and creator of The Bed Consultant. His career in the bed industry began in 2002. After graduating from university with a degree in Business Administration, Tony joined one of the largest independent furniture retailers in the UK as a bed consultant. Tony has helped thousands of customers find the perfect mattress.

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