Mould Issues

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networkn

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# 205001 26-Oct-2016 10:07

Hi.

We live in a 12-year-old (owned from new) brick and tile place in Auckland. Over winter after a few years, we noticed that net curtains were getting mouldy (light) and after a few years basically falling to pieces. We also have drapes which were getting a bit of mould as well.

We had the bathroom remodeled a few years back and in the past 12 months, for the first time ever we seem to have a mould problem in that new bathroom. It started on the bottles of shampoo etc, but now seems to be pretty much everywhere. We have used bleach and washed it off a few times, we thought, pretty thoroughly, but it comes back within a few weeks.

We don't believe anything fundamental has changed in our living habits, but don't understand why after so many years, now we have a mould problem.

We are wondering if potentially we have dampness behind the walls or something similar? Is there such a thing as a service who come in and find the source?

We consider ourselves clean and conscientious owners.

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# 1658015 26-Oct-2016 10:31

You can have building inspectors view the property and provide a report which can indicate moisture levels in walls. They use a small digital meter which outputs a % value of moisture found between two probes they press into the wall/floor/whatever.

It's not 100% accurate (because the probes tend to be no more than 50mm apart), but in your case they could analyse areas of the bathroom to give you an idea of whether the walls are retaining excessive moisture. It may be that prior to the renovation the wall linings/room configuration/forced and/or natural ventilation was able to manage the moisture better. Older linings are typically more porous (although 12 years ago gib was still pretty much as it is now), and if the shower/whatever was closer to an open window then natural ventilation would also play a part.

networkn

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# 1658017 26-Oct-2016 10:35

I am not sure if it's just that once we got mould, we didn't get ALL of it, so it's spreading again? Could that be the case?

We don't run the dehumidifier as much any-more because we were told the heat-pump in the bedroom (Bathroom in question is ensuite) would cover it.

Maybe it's just an accumulation issue.

MikeB4

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# 1658020 26-Oct-2016 10:41

sometimes this can be a result of over insulating and heating. The house needs to breathe. A previous house had this and we fitted security stays on windows to allow them to be open enough to allow airflow during the day and the problem went away.

You will need to treat existing mould to kill the spores.

Mike
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Disrespective

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# 1658029 26-Oct-2016 10:50

Almost all heatpumps will only dehumidify when cooling, so just by virtue of having one it may not help year-round. YMMV.

I would think it unlikely that you could stop mould repopulating a room by solely removing the existing mould growth. Even if you removed 100% of the spores, they are not only tiny, but can/will spread easily. They're in the air you breathe, clothes you wear etc. The reason they grow is the warmth and moisture levels are ideal for growth. Fix one/both of those issues and the problem will reduce.

jonathan18

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# 1658030 26-Oct-2016 10:54

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What surface is the mould initially reappearing on? Bleach will only kill mould, I understand, on non-porous surfaces - so if it's on surfaces like tile grout etc, it's going to come back.

Is there anything you can do to improve airflow in the room, such as leaving a window partially open (or fully open for a period each day)?

networkn

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# 1658031 26-Oct-2016 10:56

Yup now the temperature is improving having a window open is an option. We will put stays on those windows. too.

It's growing on the gib/paint primarily. It's not on/in the grout thank God.

cynnicallemon

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# 1658034 26-Oct-2016 11:08

networkn:

Hi.

We live in a 12-year-old (owned from new) brick and tile place in Auckland. Over winter after a few years, we noticed that net curtains were getting mouldy (light) and after a few years basically falling to pieces. We also have drapes which were getting a bit of mould as well.

We had the bathroom remodeled a few years back and in the past 12 months, for the first time ever we seem to have a mould problem in that new bathroom. It started on the bottles of shampoo etc, but now seems to be pretty much everywhere. We have used bleach and washed it off a few times, we thought, pretty thoroughly, but it comes back within a few weeks.

How often do you wash your nets and drapes?

How often do you open your windows in the house?

I assume the bathroom refit included a sufficient heatlamp/extractor fan?

Mould will grow on fabrics easy so I would clean your nets, drapes and other furnishings like couches and carpets about every 2 years. Also mould will accumulate on dusty surfaces too so keeping the place fairly dust free will help. Also, if you can, lightly wash walls with soapy water and a soft, non abrasive cloth. If you do all of this you house will be less mouldy and smell a lot fresher too.

Opening windows and letting in fresh air is a big help, so many homes I see these days never have a window open as they have heating/ventilation systems and while they are good, nothing beats opening some windows around the house.

NZ is a damp place to live in general, had a house which was a year old when we got it and we had mould problems after a year or two. The house was fine, it was just where we were in Northland at the time, very humid.

MikeB4

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# 1658038 26-Oct-2016 11:12

areas folks often forget when treating/cleaning mould is behind furniture, especially bedroom furniture. This is why we have dumped our dressing tables etc and only have small beside tables and a wall attached headboard. Our nets are cleaned fortnightly.

Mike
Retired IT Manager.
The views stated in my posts are my personal views and not that of any other organisation.

There is no planet B

cynnicallemon

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# 1658041 26-Oct-2016 11:20

I find that with nets and curtains, inside window moisture is the biggest problem. In winter months I squeegee the insides every morning as there can be a considerable amount of condensation.

MikeB4

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# 1658042 26-Oct-2016 11:24

cynnicallemon:

I find that with nets and curtains, inside window moisture is the biggest problem. In winter months I squeegee the insides every morning as there can be a considerable amount of condensation.

Glad we don't need to do that anymore. Since moving into our current home, a Lockwood our windows and sills never get wet. It could be the high ceilings allowing good air flow.

Mike
Retired IT Manager.
The views stated in my posts are my personal views and not that of any other organisation.

There is no planet B

MikeAqua

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# 1658091 26-Oct-2016 12:32

Mould will generally establish and persists in any damp area.

Ventilation (mechanical or passive), followed by a clean up generally deals to it.

Mike

richms

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# 1658138 26-Oct-2016 13:33

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Aircons do nothing for dehumidifying unless you put them on dry mode, and that will chew up more power than a standalone dehumidifier does when it has to heat the room back up and then switch to cooling. Plus they tend to stink when changing modes back to heating as the moisture on the heat exchanger evaporates off, defeating the dehumidification it did in the process.

You have 3 options really, ventilate, dehumidify or stop breathing/cooking/showering/etc in the house.

Richard rich.ms

SepticSceptic

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# 1658301 26-Oct-2016 15:57

Treating Mould - Bleach-based products only bleach the spores, and doesnt do anything to kill them.

Borax works, believe it or not. Kills the spores, right down into the wood etc grain.

Have a shower that has no external venting, and would regularily build up mould along the ceiling, corners, etc.

A good dousing with borax solution has eliminated the problem for at least the last 18 months.

Unfortunately, borax is now becoming harder to find, as it it classified as some kind of poison ( salt is more poisonous than borax ? ). Found the last lot at a Binn Inn. TradeMe as plenty at the moment.

http://blacktoxicmolds.com/borax-kill-mold.php

My thoughts are no longer my own and is probably representative of our media-controlled government

MikeAqua

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# 1658704 27-Oct-2016 08:18

he world is full of mould spores. It will keep coming back until the damp is removed.

Mike

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# 1658774 27-Oct-2016 10:17

I have ongoing mold problems. Bleach is only a very short term 'fix' , and everywhere Ive used bleach too often the
paint is ruined (flaking off)
I'll give borax a go .

What helped minimize it for me was
2 rooms have dehumidifiers in them. I store anything that I dont want to get mold damage into those 2 rooms ; especially cameras, mold loves to grow
on camera lenses . To dehumdify the whole house would cost a fortune .
Anti mold paint. It really works . Its not perfect, after 3 years I have a few little spots where I used antimold paint, but nothing like it used to be.
An open drain around the house, to redirect rain runoff.I leave 2 windows open all through the day.. Not an option for most unless the windows are high enough that none one could climb in.
I open every window when I get home , even if its only for 1/2 hour

The only way for me to be completely rid of mold will be to sell the house & move .

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