My mattress smells – how should I clean it?

If your mattress smells, you need to get to the source of the smelly problem before tackling it with any cleaning products.

Is your mattress brand-new?

The ‘new mattress smell’ is a quirk of buying a mattress caused by chemicals in the mattress evaporating when the mattress is unpackaged.

This process is called ‘off-gassing’, where moisture in the mattress evaporates, releasing gaseous chemicals called volatile organic compounds (VOCs). This process lasts one to two weeks, so all you have to do is wait for it to stop.

You can accelerate off-gassing by airing your mattress outside and temporarily mask the smell with fabric odour neutraliser spray.

If after two weeks your mattress still stinks, ventilation is vital – open a window, prop your mattress up against a wall and direct a fan towards it. Leave it on all day (best to do it when you are in) and repeat for three days.

Does your mattress smell mouldy or damp?

If your bedroom is damp (basement dwellers know this all too well), your mattress will have a damp, mouldy smell. Unfortunately, this is the most arduous smell to eradicate because it penetrates deep into the mattress.

Try these steps to get good results:

1. Dry your mattress for a week – outside is best, but any room with a fan will do.
2. Take a wet vacuum cleaner to the mattress with an anti-mould fabric cleaner – do the mattress’s top, sides and bottom.
3. Let your mattress dry overnight.
4. Repeat steps 2 and 3 up to three times.
5. Let your mattress dry thoroughly and spray it with a fabric odour neutralising spray in a scent that you enjoy.

A wet vacuum with anti-mould detergent is the ONLY way to remove the damp smell from a mattress – you need to penetrate more than the surface!

Does your mattress smell cheesy?

A cheesy mattress smell is caused by dead skin cells and sweat accumulating on the mattress’s outer cover. Bacteria grow and feed on the concoction, emitting smells that would make even the hardest noses gip.

You can get rid of a cheesy smell with a sponge, a bucket and anti-bacterial soapy water – don’t use a spray because you want to get the mattress damp.

By getting the mattress damp, you can work the detergent into the outer cover and suck up the moisture containing the bacteria.

Sometimes, the smell can penetrate the outer cover and seep into the sponge/fibre comfort layer. If the smell goes this deep, use a wet vacuum.

Has someone had an accident?

Whether it’s you, your dog, your cat or your child, urine and faeces are the death knell of any mattress. Thankfully, if you deal with it early, it is unlikely to cause any long-term smells that make you reach for the cleaning spray.

Here are the best steps:

1. Remove all bedding immediately and soak up whatever’s on the mattress with a damp sponge or paper towel.
2. Remove all bedding if the stain is dry and go to step 3.
3. In a bowl or bucket, create a solution of two parts water, one part baking soda and one part vinegar — this neutralises salts in urine.
4. Take a sponge soaked in the solution and work it into the stain, wetting it thoroughly before drawing the contaminated water back.
5. Repeat this process until the stain has disappeared or until there isn’t a smell.
6. Let your mattress dry.

Dealing with general smells (dry method)

If you can’t pinpoint a stain or smell, remove the bedsheet, cover the top of your mattress with a layer of dry baking soda, and leave it on for four hours. The baking soda will draw out the moisture in the mattress and neutralise top surface odours.

Hoover the baking soda off after four hours and see if it helped. If so, voila! If not, try a deep wet clean using the steps in our accident section above.