How to treat mould naturally

September 11, 2018

Natural ways to treat mould in the home

If I had a dollar every time someone asked me about mould.....I'd be a very happy person. Mould is a mystery to all of us and when I inform people that bleach is only whitening the colour of mould, NOT killing it, they gasp. 

So I wanted to debunk some of the common questions that I get asked at pop ups, activations and events. And I brought in the big guns. Meet Deanne Hislop, a Building Biologist with a wealth of knowledge. She comes through your house like gadget man and scopes the hidden nasties that could be lurking and potentially affecting your health. She loves mould almost as I love puss (too much info sorry) and below she answers the questions we all want to know the answers to. Go Deanne!

1. What is mould?

Mould is everywhere, it is natures greatest decomposer and without it there would be no life on Earth. Unlike plants who make their own food, mould needs to eat and eat like a growing teenage boy, making it a saprophyte. While mould will use almost anything as a food source, its favourite foods are cellulose materials such as anything made from wood such as timber, woodchip, cardboard, MDF (which is known as Maccas for mould in the industry) clothes, leather, insulations, glues, dust and plasterboard with its least favourite food being inorganic materials such as rocks and concrete – it would be very rare to see mould on these. It is suggested that 1 in 3 Australian homes have a dampness of mould issue.

Mould needs three things to grow – Moisture, oxygen and food. In reality, only one of these are in our control and that is moisture. A mould issue should always be addressed by identifying and rectifying the moisture source. This may be humidity through occupant behaviour such as the use of humidifiers, drying clothes inside with limited air exchange (not opening your windows and doors in most cases), gutters that have not be properly maintained causing water to back up and allow moisture intrusion into the roof cavity, a slow pipe leak on an internal wall, missing grout, or even silly things such as poor landscape design, reticulation spraying external wall or gardens sloping towards the house. Additionally, any building material that has been wet for more than 48 hours is likely to contain mould.

A Building Biologist is equipped to sample, identify and provide remediation advice as well as any other environmental factors that may be at play in the built environment such as chemical exposure, allergens, EMF and water contaminants.

2. How much mould is normal?

Firstly, there is no hard and fast answer to this. If you fall into the 24% of the population that is unable to create antibodies to mould then your threshold for mould exposure is decreased, if you then fall into the 2% subset of that, who will create an extreme inflammatory response, then you mould exposure need to be even lower. On top of that we have different genres of mould which exhibit difference responses in the body. Certain moulds produce proteins, mycotoxins and mould volatile organic compounds (MVOC’s) which can cause people to react to very strongly. Mould can cause both allergic and inflammatory responses in people. Mould can be associated with everything from a low level of fatigue to hospitalisation, there are so many factors involved.

3. Why is mould so bad now?

I see five main reasons as to why mould is a bigger issue now than previously.

Firstly we are on a mission to create air tight and energy efficient homes. Energy efficient homes have very limited natural ventilation – think plastic bag! This leads to increased condensation especially because of occupant behaviour. Leaky, breathable homes seem to be a thing of the past.

Secondly, poor build design and practices. The number of homes I see that have inadequate drainage and roof plumbing often draining directly under the slab, lack of eaves, windows that open from the bottom outwards not allowing steam to escape, or windows that don’t open at all, tradesmen putting extractor fans in the wrong place or don’t externally vent them, poor insulation, cracked grout and lack of silica and caulking etc –in fact I could write a book on bodgy buildings!

Thirdly, just as we have created a long list of super bugs through our love of antibiotics and antibacterial agents, the introduction of fungicides in our build materials, paints and some soft furnishings has seen the creation of super fungi/moulds that will often outcompete the less aggressive species.

The second last reason is that we are simply using cheaper man-made materials like MDF, plywood, chip or particle board and oriented strand board these materials contain chemicals such as adhesives and formaldehyde which change the pH of the material and consequently change the genre of moulds that grow indoors as a result. To add to this, these materials are about as attractive to mould as a clean house, glass of wine and chance to go to the bathroom alone is to a mum of six……

And lastly, I believe EMF (electromagnetic fields) through wireless radiation, cell phone towers etc play a huge role in both amplifying mould in the environment as well as its effects on the occupant. There is adequate research to suggest that not only does it increase the access of biotoxins to the brain through increased permeability of the blood brain barrier, but it can also set up a flight of fight response in the body reducing the body ability to detoxify from mould exposure. 

4. Does bleach kill mould?

Bleach is a biocide and is often used as a food source by mould which means that you are never actually getting on top of the mould issue, instead you are simply making it less visible, because you are bleaching the colour out of the mould itself.

5. If I don’t use bleach, what can I use to remove the visible appearance of mould?

To keep mould away, moisture should be addressed, drying your shower after use is a great example as well as increasing the ventilation in the home. If you have a condensation issue, you will probably have a mould issue somewhere. Keeping dust to a minimum will help mould growing off surfaces such as windows and window frames where condensation often occurs. Using a HEPA fitted vacuum cleaner will trap and remove mould spores from carpets and soft furnishings as well as hard surfaces.

All mould should be physically removed as opposed to just trying to kill it – which is not recommended in large areas and we understand that dead mould can be just and at time more harmful than viable mould. Removal should be with a HEPA fitted vacuum, microfibre cloth or by removing the material itself. A great example of this is to replace your silica every 12 months – it is impossible to clean mould from silica once it is in.

Lastly a solution of a few drops or oregano, a squirt of dishwashing liquid and some water in a bottle is a perfect mould solution for surface cleaning and best used in conjunction with a microfibre. Oregano is by far the best for preventing mould growth and the dishwashing liquid will help to break down the biofilm over the colonising mould to allow the oregano to do its job.

6. How can mould affect our health?

One thing to remember is that you don’t need to see or smell mould for it to be an issue. Mould can be a cause for increased asthma attacks, headache, allergic reactions, sinus infections, allergic rhinitis, fatigue, chronic inflammatory response, digestive issues, muscle aches and pains, chemical sensitivities, respiratory and chest infections that often do not respond to antibiotics, mental illness and skin issues to lung disease in children and cancer.

About Deanne

Deanne Hislop here, author, speaker, building biologist and mum of two beautiful firey redheads. Deanne is a certified Building Biologist and practitioner member of the Australasian Society of Building Biologists. She practices through Western and South Australia and runs numerous workshops and seminars from beginner to practitioner level. She is also the founder of where she practices geobiology/geomancy and energetic healings. If you need to seek advice for your home you can get in contact with Deanne via her Building Biology WA website