Dear internet hive mind,
I humbly request your opinions / knowledge / counsel.
TL:DR; We moved into a new unit and (accidentally) brought mould with us. It spread madly. We've cleaned away 95% of it or so. We bought a humidity monitor and it seems we are always between 59% to 67% humidity, despite having two windows permanently open, doors open, wardrobes open, running exhaust fans and the rangehood etc. Is it just going to keep growing back?!
Full story:
We (accidentally) brought some mouldy items with us when we moved into a brand new ground floor 2 bed 2 bath unit in early Feb this year. The mould spread fast in the smallest bedroom (which we were using as temporary storage) before we noticed it. When we'd finally noticed it, it had spread to the main bedroom wardrobe, and started to appear throughout the house as well: mainly on fabrics and clothing, eg handbags, backpacks, dark clothing, shoes.
Up until then, we had always used the exhaust fans in the bathrooms, but admittedly we didn't open the windows at all for a few weeks (waiting on a flyscreen).
When we noticed the mould, this is what we did:
* Threw out the worst of the mouldy stuff
* Immediately bought damprid and put some in the worst bedroom, and some in the wardrobe of the main room
* Started keeping 2 windows open 24/7 for ventilation
* Kept using exhaust fans as normal in the bathrooms, but now [/also/] left them on for longer (even after we'd finished the shower)
* Cleaned about 95% of the leftover mould - this has been a long process because I had to take out ALL our clothing in the main wardrobe, and towels/linen, and shoes… and wash it all.. and dryclean some.. etc.
* We don't run any heating, we don't have any indoor plants, we never dry clothes inside, no fish tanks, we cook with lids on and a rangehood.
Before putting everything back into the wardrobe, I wanted to check if our home still had conditions that were conducive to the growth of mould - despite the list above. So I bought a humidity meter - I know it's probably inaccurate as it was a cheapie… but it reckons we are at 60 - 67% humidity all the time, which seems far too high.
Is the mould going to come back? Why is our humidity so high? What can we do about it? Even with all our windows open, and a sliding door open, and a rangehood whenever we cook (not much), and exhaust fans that run longer than needed, and every internal door open… we can't seem to budge that number.
By doing some reading, the internet said there could be a leak somewhere in the walls or floor… but according to the humidity meter we have, it's about the same all around the house.
We tried the "dry" mode on our ducted air con, and it works! Got it down to about 56%. But it makes the room verryyy cold despite checking the temp settings.
H E L P. Is your home's humidity also high? Can we do anything, aside from just buy a dehumidifier for the whole house and a crapton of damprid? Is this common in new builds? I am sick of cleaning, and paranoid it'll be back.
Thank you so much in advance for any thoughts you have.
PS: We are in Sydney.
Answered your own question. You need heating.
Any humidity in the air will condensate on cold surfaces.