July 2020

Mattress mould; Why it happens and how to treat it

Mattress mould can pose a real health risk in the bedroom. It can come as quite a surprise as you lift back the sheets to discover a dark sprawling stain on your mattress from mould. In this article, we’ll look at the common questions as well as solutions to your mattress mould issues.

Mould growth is predominantly caused by humid environments, sweat, moisture or stains. Factor in that the human body perspires during sleep to cool down and there are many contributing factors. This guide will help you avoid mattress mould.

No mould here; mattresses should be turned and kept well ventilated

Why is my mattress mouldy?

Please note that no new mattress is constructed and sent out with mould. New mattresses are made in clean factory environments and then bagged and sealed before being sent out. The mouldy mattress phenomenon is always caused by environmental factors.

So what should you look out for?

Mould needs a humid environment

Mould needs moisture, food and an optimum temperature in order to thrive or grow. The moisture could come from the water released by the human body during perspiration and a humid room would encourage this even further. Food is not food in the literal sense but rather materials such as cotton or even dead skin found in a lot of mattresses. It is this combination of moisture and food that enables mould to develop. It’s entirely preventable with mattress maintenance and care.

Subsequently, mould spores thrive the most in temperatures between 21 and 30 degrees Celsius. Comfortable room temperature is around 20 degrees.

Stack of cheap thin mattresses
Mattress mould is caused by a mix of humidity and bacteria. Mattress maintenance can ensure mould never affects your bedroom.

It is worth noting that mould spores are always present to some degree in the air, so a humid environment is what encourages growth. It’s this excess moisture that you need to combat. Drying clothes on radiators or clothes maidens in the bedroom should be avoided where possible.

An effective solution to a humid room is either consistent airing of the room or purchase of a dehumidifier or air purifier if not possible. This will help to reduce any unnecessary moisture in the air and subsequently make it more difficult for dust mites and mould to grow.

Mould is caused by humidity in the bedroom
Mould is caused by humidity in the bedroom
Ventilation and regular mattress maintenance can prevent it
Ventilation and regular mattress maintenance can prevent it

Mattresses kept directly on the floor

You will often see the initial signs of mould on mattresses that are kept directly on the floor or on cheaper solid top bases. This is because the mattress underside gets zero ventilation meaning that any moisture can build up leading to mould. This is also why some short-term rental properties end up with mattress mould, as mattresses can be left for months without any mattress maintenance or ventilation. It is the build-up of heat and moisture that then enables mould to thrive in this scenario.

Mouldy mattresses on the floor
Mattresses should never be kept directly on the floor. They are more likely to become mouldy and damaged. They should always be on a suitable mattress base.

How often have you stayed somewhere short term and thought ‘I’ll turn the mattress’ and open the window, probably not much! We always recommend you turn your mattress monthly which should help keep any potential mould problems at bay. Remembering that its only in rare cases of high humidity and lack of ventilation that mould takes hold.

What to do if your mattress develops mould?

If your mattress does develop mould then there’s no need to panic; it can be removed by following the mattress maintenance steps below.

  • You would first need to vacuum both sides of the mattress thoroughly. Even on a non-turnable mattress, it’s advisable to thoroughly vacuum both sides. Once you have done this ensure that you fully empty your vacuum in order to prevent any further spread of the mould.
  • Using warm soapy water use a circular motion to clean the affected area with a damp cloth. Ensure that you do not soak the cloth that you’re using as this will only exacerbate the situation by adding further moisture to the area.
  • Once this is done allow as much air to the mattress as you can in order to let it dry and ventilate. The ideal way to do this is to allow direct sunlight to the mattress. If this can’t be done, just allow as much air as possible to it.

Mould on a mattress is a product of the environment in which it is kept and is not caused by the mattress itself.

How to stop your mattress getting mouldy

As part of correct care and maintenance, we always advise to flip over any fully turnable mattress once a month as part of your mattress maintenance. By doing this you will highlight any potential mould issues as well as allowing the mattress to ventilate evenly, particularly where the mattress is on a solid top base. All of our mattresses have side handles enabling much easier turning of them.

If you don’t turn your mattress frequently this can result in uneven settlement in your mattress, where lumps and bumps may form. This is because you’re not evening out the wear of the internal fibres of the mattress on both sides.

Origins Pocket Reflex 1000 on a Cream Chenille base
Turn and rotate your mattress monthly. Avoiding one-sided mattresses where possible.

If you’re looking for more mattress help and advice why not check out our ultimate guide below, it could save you a fortune when you next buy a mattress.


Reducing humidity such as drying clothes outside of the bedroom if possible and opening a window each morning will greatly reduce the potential of mould occurring. If really advanced mould is found on your mattress the best option is to replace the mattress. Mould spores can really impact your breathing and exacerbate asthma and other respiratory problems.

If you need help then please get in touch with us for a friendly chat on 0161 437 4419.

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