Why Dry? Everything You Need To Know About Why Items In Storage Need To Be Dry

Many of us may remember a shampoo ad that suddenly switched from glossy swishing hair to ‘And now for the Science’ bit. What ensued was a whole lot of impressive-sounding jargon. Unsurprisingly it’s never been quite as long-running as ‘because you’re worth it!’ because it was blinding us with science.

So, fear not. I’m not about to launch into the benefits of hyaluronic acid or biotin, or its equivalent in the world of packing boxes. No chemical equations follow. Just some good sound science to persuade you that anything you store away, whether with us at easyStorage or elsewhere, should be clean and – most importantly - dry.

If you’re squeamish, you may want to take my word for it and step away from the screen now. Because I’m about to talk about fungi and mould, and it’s really quite stomach-churning.



Mould is found everywhere and is part of the natural environment. Outside, moulds break down dead organic matter (fallen leaves and dead trees) making them invaluable to nature.

They can grow almost anywhere moist. To reproduce, mould sends out spores. Carried by air, if these spores land on any moist surface that can sustain them, they start growing. And by ‘sustaining’ I mean ‘things that they can eat’. Indoors as well as out.

Mould produces enzymes that break down proteins and cellulose for food for it. Yes, mould isn’t growing on your things. It’s eating them!

Whilst the average fridge is a banqueting ground for moulds, most moulds like temperatures above 40 degrees to survive. Most fridges are set at 39 or below. However, moulds are by no means fussy eaters. They’re particularly partial to natural (plant) fibres like cotton, and linen. Wool and silk aren’t top of their ‘munch list’ and therefore are slightly less susceptible (thanks to being made of protein rather than plant-based fibres), but given a little moisture, no self-respecting mould spore is going hungry and dying. It’s going to munch away for survival. Even leather makes a tasty host. It will even enjoy some synthetics like paints and glues.

It’s not so hot on anything inorganic like glass or concrete, but any dirt, dust or organic residue on the surface of these things (like a shower glass, for example) is fair game.

Don’t think that because you can’t see it it’s not there. Spores can bide their time. They don’t die because they don’t have water or food. They simply hang on in there until they find the right conditions: water, food, temperature and oxygen.


The difference between mould and mildew

Mould and mildew are often confused. Mildew is a particular mould type. Both are fungi. Moulds are fungi that grow in what are known as ‘multicellular strands’ called hyphae. They are only visible ‘en masse’ to the human eye, not individually. (The scientific term for mould when it’s got big enough to see is mycelium.) They are all interconnected. Once they reach this point 0 big enough to see with the naked eye - the damage is usually done. If the item’s not already irreparably damaged in appearance, the smell and the spores may linger. Without very good reason, it’s almost always better to dispose of these items than to try and fix them, sadly.

Most moulds are slime or fuzz, raised in appearance, and blue, black, green or even red in colour. They have a strong, pungent smell. Mildew, by contrast, looks white or grey and is usually flat and powdery. It smells musty, like damp socks that haven’t been put out (or in) to dry, and it particularly loves damp to thrive in. It also lives pretty much on the surface of things, so isn’t quite as damaging as many other moulds, which burrow on down. That doesn’t, however, make it desirable or ‘ignorable’.


The dangers

A Microbial Volatile Organic Compound (MVOC) is what creates those smells (and most mould produces more than mildew). MVOCs are released by the metabolic processes – the chemical reactions - of fungi and bacteria, which cause decay by digesting the carbon in anything they grow on. Exposure to MVOCs is believed to cause many illnesses caused by exposure to mould, although research is ongoing. Symptoms include blocked/runny noses, sore eyes, sneezing, coughs and wheezes, breathing problems including infections and worsening asthma and allergies. This is particularly true - and particularly risky - for anyone with a weakened immune system or existing lung diseases.

There is also a risk of mycotoxin poisoning if clothes infested by toxigenic moulds are not effectively decontaminated before wearing. But decontamination may not be possible.

Once anything absorbent or porous, like carpet or clothing, has grown mould, it may be almost impossible to remove it completely. Mould can grow in the smallest of spaces, even the tiny ‘holes’ in the weave of the cloth. Most mould infected fabric will need throwing away if it’s not to continue smelling out your home and/or infecting other items with its spores. Even dead mould can create allergic reactions in some people: it is not enough to simply kill it. It has to be removed.


Can you get rid of it?

Allowing air to circulate can help dry any dampness and dislodge spores, which is why we always suggest leaving a little ‘breathing space’ at the top of packed boxes in storage, but it’s far better to starve them of moisture, and therefore food, in the first place. There is no practical way to remove all mould and mould spores from the indoor environment. The only real way to control indoor mould growth is to control moisture.

So when you store things away, even in the most airtight of spaces, storing dry is definitely storing safer when it comes to keeping mould-free.


As the storage experts, we have plenty of advice that you may be interested in, like tips to keep those boxes dry whilst moving in wet weather or protecting your furniture before putting it in storage!

This advice comes to you from easyStorage, the low cost self storage people who make it easy for you.