House Cleaning Tips – Getting Rid of Mould at the End of Your Tenancy

By Nick Vassilev

updated: 18/01/2023


Mould Is Everywhere In The House

Here is a bit of a disclaimer. A quick story. I was renting a flat in West London until last year. It was a lovely place that made a great home. The apartment was my little castle and forward base.

As all good things my tenancy at this lovely property came to an end and I had to return the keys. Before I did that How to remove mould from carpetsthe landlord’s letting agent sent an inventory clerk to carry out a check-out survey and prepare a report that reflects the current condition of the flat I was returning back to its owner. To my bitter surprise the inventory clerk found a number of missed/problematic areas that failed on the report. One of the issues highlighted was the presence of mould almost everywhere – in the bathroom, in the kitchen, along the window sills, everywhere. I thought it was something I could not get out with my modest amount of elbow grease and therefore not worried about it too much. It turns out, however, according to the letting agent, of course, that I was responsible for the mould removal.

I was shocked and at the same time I was gutted with my indecisiveness. I had the opportunity to book a West London end of tenancy cleaning company which offered to treat mould. The didn’t offer any guarantees (I completely understand that, mould is tricky) however they could have treated it with their professional  cleaning materials and the results would have been much better than my pale attempt.

During my university student days, I flatted with a microbiology student. As one assignment, she had to grow mould cultures taken from various parts of the house, including the refrigerator. I know, exciting stuff, but this is the toad to greatness, a wise man said.

Petri dishes with revolting grey, white, orange and black substances kept cropping up all over the house. This is one of the few situations in which someone would actually want to have mould around. Most of us want to eliminate mould from the house – especially if you’ve seen a Petri dish with a particularly repulsive culture in it.

Getting Scientific – What is Mould?

As my flatmate informed us, mould needs several things to grow. Mould needs water, food, the right temperature and time. Eliminate these things and mould will not be able to grow.

Keeping things at the right temperature to prevent mould is not practical for most parts of the house. Fridges are kept at about 4°C but mould still can grow inside the fridge, given enough time. After all, my flatmate got an orange-coloured culture from inside the fridge and we’ve all found something covered in blue mould at some point in our lives. And don’t forget that the beneficial bacteria in live yoghurt survive quite happily inside your fridge. Freezing and boiling are the only temperatures that mould can’t survive in – but neither can we.

How Does Mould Grow?

Eliminating food for mould to grow on can also be difficult. Minute particles of skin, dirt or dust can provide sufficient food for mould to grow in, even in the most unlikely places.

Mould On Windows

Windows, for example, don’t appear to have anything smeared on them, but mould can still grow there. However, any smears of a biological nature (e.g. handprints, food splatters) should be cleaned off as soon as possible before they have time to grow moulds.

Eliminating moisture is a big factor in preventing mould and is much easier to achieve. Window condensation is particularly prone to growing mould if it is allowed to settle or pool.

Reasons For Mould Growth

Mould (mildew) can also grow in places with poor ventilation and rising damp combined. Some older houses (especially those with wooden flooring) can have particular problems with rising damp, but fortunately, they also have good ventilation. Problems with mould and rising damp occur when air is not allowed to circulate in or around items – mildew can often occur on stored items that get damp but can’t breathe (e.g. if wrapped in plastic or packed tightly into a container – my grandmother accidentally ruined some vintage clothing and books this way). Bathrooms are also prone to moulding. An extractor fan – or an open window – to allow steam and damp to escape is vital.

How To Remove Mould

But what if it’s too late to prevent mould and you already have greenish-black dots on your windows or walls? The first step is to attack any surface mould and kill it off. Household bleach (chlorine bleach) in a 10% solution with water is an effective mould-killer, although you should not use this on areas that will be damaged by the bleaching effect (e.g. curtains or soft furnishings). Mould can also be removed by using natural home cleaners as neat (undiluted) white vinegar, as the strong acid kills the bacteria forming the mould. Do not merely wipe mould away with soapy water, as the mould spores will need to be killed. And always remember to dry the area as best you can after using the bleach or vinegar treatment.

If the mould is more than surface deep or if it comes back after treatment, stronger measures will have to be taken. The affected item will have to be thrown out before the rot spreads further.

In summary, here’s a quick checklist of how to deal with mould.

1. Check: is it surface mould or deeper? Throw out anything with deep mould.

2. Wash off any surface mould.

3. Check again after a week or so for any reoccurrence. If mould has reoccurred, then it is deeper mould and the affected item needs to be thrown out.

Incidentally, this is the advice given in some of the more obscure passages of law given in the Old Testament – old advice and it works!

About the author 

Nick Vassilev

Nick blogs about cleaning. He is a cleaning expert with more than 25 years of experience. He is also an NCCA-certified carpet cleaner. Founder and CEO of Anyclean.