How to remove Mould on walls and ceilings.

​What causes mould?

​Most people think mould in their home is caused by some sort of leak. But in my entire career as a painter (and all-round wall/ceiling obsessive) I’ve come across leak formed mould … once.
 
The vast majority of Mould outbreaks are caused by:
 
too much CONDENSATION (man-made dampness)
plus
too little VENTILATION (air movement).
 
With cooking, washing, using a clothes dryer and just breathing, an average family can create up to 15 litres of air born moisture a day!
 
Which is fine if the windows are open and a lovely fresh breeze blows all that moisture away.
 
But in winter, doors and windows are shut, heaters are on, and ventilation all but ceases. AND your nice warm, cosy interior meets your homes cold exterior. The difference in temperature turns water vapour into … water. A winter home is like an inside out can of frosty beer on a hot day. Cold meets hot and water condensation occurs.
 
Mould loves condensation. Mould loves a lack of air movement. Mould loves warmth. And mould loves a nice porous surface to hook into (walls and ceilings).
 
As a result I get heaps of calls from people concerned about a sudden and unexplained mould outbreak at the end of winter.
 
At other times of year I’ve seen mould behind pictures, pianos and other wall hugging furniture and in high corners of under-used rooms. This is all caused by a lack of air circulation.

​Should I be terrified of mould?

Condensation formed mould - DIYable

Leak formed mould - call an expert

​Everyday condensation-formed mould is not healthy. It can irritate the breathing of asthmatics, babies and old people. But its not nearly as dangerous as people think. I’m an asthmatic and I clean it up all the time.

And look at me! Apart from occasional blindness and a near total loss of memory, I’m fine!

​(That was a joke).
 
Leak-formed mould is more serious, often because it has sometimes been growing for years. It is usually embedded in the fabric of your building. Expert removal is required. (And condensation-formed mould that has been left to run rampant for years would need expert removal too.)
 
Unfortunately a visit to Dr Google is full of horror stories implying that your basic surface mould is some sort of deadly killer. These stories are brought to you by mould removal companies. They are probably brilliant at removing the really nasty stuff but are not essential for basic surface mould.

How do I get rid of mould?

Google again offers about 10,000 different ways but the general idea is as follows:
 
STAGE 1 - Put on a mask and remove what you can by any of the following:
 
1. Vacuuming (using a special HEPA filter so the mould spores don’t shoot out the other end of your vac).
 
2. Wiping and rinsing with dish washing detergent and water.
 
3. Wiping and rinsing with Vinegar.
 
4. Wiping and rinsing with Baking soda diluted in hot water.
 
5. DON’T USE BLEACH. Its pretty noxious and while whitening the area, it does not kill the mould. Someone said it was like a shaving a face – the visible whiskers are gone, but the roots are strong and healthy and will push up more whiskers tomorrow.

6. DON'T MIX CHEMICALS.  The results range from 'turns into water' to 'turns into poisonous gas'.  If you want to use various mould killers, do them one at a time and let each one dry before applying the next.
 
STAGE 2 – Put your mask back on and spray or wipe and leave 24 hours with any of the following:
 
1. A few drops of Oil of Cloves diluted in water.

2. A few drops of Tea Tree Oil diluted in water.
 
3. Vinegar.
 
4. A product called Mould Action (available at Bunnings)
 
The key here is to let your chosen fluid just soak deep into the mould roots then DRY OUT. Wait until the next day or longer before moving to the painting stage.
 
STAGE 3 – Paint with added mould inhibitor.
​
The previous 2 stages will kill most of the mould but will usually leave a few stains and marks. (That’s why people love bleach – everything ‘looks’ white. Don’t do it!)
 
1. Paint the affected areas with a good quality mould killing primer. I use Dulux Precision Stain and Mould Blocker. This hides the stains and works long term on any mould roots that have escaped the previous stages. It also seals and hopefully suffocates these escapees.
 
2. Paint one or two top coats with a quality ceiling paint. I use Dulux Ceiling White which comes with ‘Mouldshield Technology’.
 
THE PURPOSE OF PAINTING IS TO CREATE A NEW, CLEAN, INHOSPITABLE ENVIRONMENT THAT NEW MOULD FINDS VERY HARD TO GROW ON.
 
And if your mould affected area is a bathroom or kitchen ceiling, here’s one more trick!
 
3. Paint the ceiling with a Low Sheen finish rather than the usual Flat finish. This is shinier and makes gripping that much harder for new mould. I use Dulux Wash and Wear +Plus Kitchen and Bathroom Low Sheen paint. In fact, that’s what’s on my own bathroom and ceiling, in an old house, and we don’t use the fan much. We’ve been mould free since I applied it years ago.

​How do I stop mould coming back?

VENTILATE, VENTILATE, VENTILATE!!!

1. Especially in winter, if you get a dry windy day, throw all your windows open and let the breeze through as many times as you can.
2. Use ceiling fans.
3. Open up unused rooms as much as possible.
4. Get vinegar or oil of cloves onto any new mould spots as soon as you see them, before they grow.
 
 
So while this is a bit of work, it’s not impossible to do yourself.
 
I’d be glad to help with your condensation-formed mould problems AS PART OF A MULTI-ROOM INTERIOR PAINT JOB but I’m afraid my business model doesn’t work for ‘just one ceiling’.
 
Click here to find out more about how I can help you.
 
Cheers Tony - The Tidy Painter.