What is Mould

By October 21, 2015 News No Comments

What is Mould?

We all know Mould is bad in our home, but what is it?

Mould can be identified by its musty odour and by the distinctive discolouration of whatever it is growing on. Mould is a collection of lots of tiny fungi and can grow both indoors and outdoors and it exists everywhere in nature to breakdown organic matter by consuming it. Mould needs 3 critical
things to grow. Removing one of these 3 things will reduce or even eliminate mould growth.

1. Source of food

Mould likes to eat Carbon atoms in organic material such as leather and soil along with cellulose such as wood and paper. Since most buildings are made from, or contain these materials inside, it’s almost impossible to eliminate these from our living environment.

2. Oxygen

Most moulds require the presence of oxygen to grow, even in very low amounts. Therefore it’s impossible to eliminate this critical factor from our living environment since we human beings also require oxygen to survive!

2. Moisture and humidity

Mould requires plenty of moisture or humidity to grow and likes conditions above 70% relative humidity to thrive (but it can survive in less). People are comfortable at relative humidity levels of 30-60%. Therefore the number 1 critical action we can do to control mould growth is to reduce moisture and humidity levels, and keep the building dry.


Bazz’s tips to reduce Mould

Three things you can do to stop mould growth:

  1. Identify the source of moisture.
  2. Remediate and remove the mould by cleaning it off or removing mould damaged building materials or furnishings.
  3. Stop mould from coming back by ventilating your home or subfloor space.

#1 Identify the source of moisture

Mould needs moisture to survive and grow therefore you or an expert needs to identify a possible source of moisture.

Is there water leaking from the roof or a pipe?

If so, fix the leak, remove and replace damaged building materials.

Is there water accumulating under your home from rain run-off or garden vegetation preventing cross ventilation causing increased
subfloor humidity?

If so, water diversion or drains may be required for periods of heavy rain. Also make sure vegetation or additions (such as a deck) are not blocking cross ventilation grills in the sub floor.

Is there moisture being trapped in your home from gas heating, cooking, showering, cleaning, bathing and the use of clothes drying racks or clothes dryers?

If so, in all cases, adequate ventilation is needed to stop moisture and humidity build up. Make sure extractor fans are vented to the outside of your home and not into the roof space as moisture can accumulate and create the environment for mould to grow.

Has flooding caused water damage?

If so, remove and replace the affected building materials. Remediate other surfaces with my mould cleaning recipe.

Leaving damp towels or clothes lying on the floor.

It’s a common problem with an easy fix. Piles of clothes or damp towels promote the environment for mould to grow and are often found in rooms with poor ventilation. These rooms tend to have a musty odour, so a regular tidy-up and ventilating the room will sort this out.

Gas heaters burn either natural or liquid petroleum gas and have no flue or chimney to take the combustion products outside.

Combustion products include nasties like carbon monoxide, nitrogen dioxide and formaldehyde, which are harmful to health if present in high concentrations. Unflued gas heaters also produce up to 1 litre of water per hour, resulting in increased humidity indoors, which can indirectly affect health through promoting the growth of mould.

If possible don’t use unflued gas heaters because they increase the risk of asthma and promote conditions for mould growth. If unflued gas heaters must be used, ensure there is adequate ventilation to the room(s) being heated to reduce the build-up of harmful gases and moisture levels. Ensure the heater and gas bottle are properly maintained.


#2 Kill the mould and clean it away

Mould Cleaning Recipe

Determine if the surface the mould is growing on is porous or nonporous.

In many cases the porous surfaces on which mould is growing will need to be thrown out or replaced if badly stained. This includes clothing, carpet and even silicone in the shower. Bleach as a remediation method is not strongly recommended because it discolours the surface mould but does not kill the substructure.

  • 1600ml white vinegar
  • 400ml distilled water
  • A couple of drops Oil of Clove
  • Couple of teaspoons Bi Carb soda


  1. Pour 50% of the solution into a plastic spray bottle, like you’d use for gardening and 50% into a bucket.
  2. Spray the affected area, leave for 5min (for lightly affected areas and 10+min for badly affected areas) to allow the solution to be absorbed into the mould and surrounding area.
  3. Wipe off with a micro fibre or cotton cloth then rinse the cloth in the bucket with the solution to prevent cross contamination.
  4. Wear protective clothing such as disposable coveralls, gloves, P1 or P2 respirator, a disposable cap or shower/swimming cap and protective
  5. It may take a few attempts to kill the mould and bleach can be used on any discoloured surfaces caused by any streaking of the vinegar, once the mould has been killed.
  6. A reminder that cleaning the mould alone will not eradicate the problem if tips #1 and #3 are not followed. Once you have cleaned the mould away you need to keep the affected areas dry and well ventilated.

#3 Keep the mould away – Ventilate!

Your home or apartment is a giant sponge which absorbs moisture created from all the activities we carry out on a daily basis when living such which has accumulated from cooking, showering, cleaning and bathing and using unflued gas heaters. After a while conditions become great for mould growth.

The of mould growth that we can control is the moisture and humidity in our homes and drive out those nasties like mouldy and musty
odours, and keep your home dry. The most cost effective way to do this is to ventilate your home. Our modern lifestyle means the house is often unoccupied and closed up during daylight hours and therefore can’t be ventilated (particularly in winter) and security concerns mean we can’t leave doors and windows open or unsecured.

  • Cross-ventilate your home by opening windows and doors as often as possible to flush-out stale air moisture and humidity. If you live in an apartment, consider leaving the extractor fan in the bathroom operating for extended periods (they generally draw only 50W electricity or less and are therefore inexpensive) as the benefits outweigh the cost of operating them.
  • Open wardrobe doors and do not stack clothing tightly, place shoes on shoe racks in wardrobes rather than on the floor.
  • Pull furniture and bedding away from walls or at least enable a 20-30mm gap.
  • Ensure that wet areas are well ventilated and that extractor fans are used during bath / shower times. Clothes dryers and bathroom extractors should be vented to the outside, not into the roof space.
  • Install a ventilation system such as Ventis to automatically flush your home all day with purified fresh air which has been warmed by the sun and use natural cooling in summer.

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