Advice on best way to stop mould on walls and ceilings in bedrooms

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#2961998 1-Sep-2022 13:45

Also check the gutters. If they impede the flow of water to the downspout it can back up and get into the ceiling/ roof space. This can also happen if the gutters are mounted too high on narrow barge boards under the roofing.

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I've been on Geekzone over 16 years..... Time flies....

pih

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#2962000 1-Sep-2022 13:50

Clima:
Cleaning down with white vinegar will certainly retard any regrowth

Ethanol (eg. Methylated spirits) is also good, and doesn't leave a smelly residue or deteriorate paper surfaces like a water based solution might.

OP: I agree with most of what's said above. My list in order of priority would be: remove sources of indoor moisture (no clothes drying, add a shower dome), increase sunlight and ventilation by removing foliage around exterior walls, check for signs of water ingress and repair it (around window frames, attic space, cladding, internal gutters leaking/overflowing, etc), check insulation is thick and tightly packed in ceilings (ie no gaps), improve extraction/ventilation, add a moisture barrier under the house of possible, sanitise walls and ceiling well and repaint with mould inhibitor, and finally improving drainage generally around the house.

Dehumidifiers are good in the interim, but they're a band aid and not a solution.

Handle9

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#2962215 2-Sep-2022 00:01

Linuxluver:

BUT!!! Be aware if you get the house assessed for the healthy homes standard...and it fails....you have 90 days to remediate the problem or the tenant can (rightly) take you to the Tenancy Tribunal for mediation and possible compensation if it can't resolved in a timely way.

The compliance date for a tenancy which started before the 1st of July 2021 is 1 July 2024. If you started the tenancy after 1 December 2020 then you should have issued a compliance statement.

There's a tool here to show you when you need to comply.

https://www.tenancy.govt.nz/healthy-homes/healthy-homes-compliance-timeframes/compliance-timeframes-decision-tool/?decisionpathway=756%2C750%2C744%2C738

Handle9

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#2962216 2-Sep-2022 00:03

tripper1000:

Long story: Property manager advised that a HRV is the norm in rentals now days and it is very rare not to have them.

The property manager is full of it. There is no requirement for this and it's not "the norm."

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#2962218 2-Sep-2022 00:09

tripper1000:

HRV are smiled upon by the standards, helping to achieve compliance but unlike the alternatives an HRV is automatic, so they're a win-win - between the landlord and law makers, houses are kept healthy despite tenant actions.

This is 100% wrong.

Recirculating systems (products like HRV and DVS systems), or fans that do not extract to the outdoors are not suitable to meet the ventilation standard.

https://www.tenancy.govt.nz/healthy-homes/ventilation-standard/

Wellingtondave

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#2963179 4-Sep-2022 21:14

Treat symptoms.

Run the living crap out of dehumidifiers. Buy your tenants a couple, pay them a dollar per day to actually run them.

K8Toledo

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#2963210 4-Sep-2022 23:55

DanielWilliamsNZ: Hi, I have an investment property that has issues in the bedrooms with mould on the walls and ceilings. The tenants said that they are ventilating the bedrooms and cleaned down mold regularly but keeps returning. I currently have a heat pump in the lounge and no issues there. I am looking for advice on how to fix this issue? I would like to keep the costs as low as possible but ensure the tenants don't have to put with the mould on an ongoing basis. I am keen to either get advice here or advice on someone who I can pay to visit the property who can advise on the best solution who is independent - the options I have looked at so far have been tradespeople who specialise in installing a particular product that they have been keen to install given they specialise in that product, but it hasn't been clear that this has been the best option for the issues.

Ventilation...notably extractor fans in bathroom? Check Healthy Homes requirements for rentals under RTA - it contains all the info you'll need.

What type of foundations does the house sit on?

AliExpress

Shop now on AliExpress (affiliate link).

K8Toledo

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#2963215 5-Sep-2022 04:46

These pics show what a bathroom without an extractor fan installed and window that only opens part way due to the water tank outside obstructing it looks like after four years.

This is the kitchen door (taken from inside kitchen), it opens into laundry.

This is the external laundry door opening to outside

The photos are mine, I took them.

They were presented during a tribunal hearing when I took the landlord to court for a slew of offenses under RTA.

I was the third tenant and had rented the flat four years.. Owner lived above.

Three times he disconnected the power to my downstairs flat at 10pm while I was on an overseas phonecall.

This happened without warning or even a text from him and the power remained off until 7am each time.

His reasoning when I finally confronted him - "he could hear me talking".

One winter the inside temps dropped to 9c, a complaint about the drafty house was overdue so I phoned the landlord

The next morning I received 3mths notice.

What the landlord didn't realize is that I'm also landlord, with rentals in another city. And I've read the RTA.

All landlords should be familiar with the act imho as well as tenants (for everyone's sake).

Yeah I could just move out....but this guy wasn't fit to be landlord; & tenants are usually oblivious to RTA. If I as tenant didn't stand up to him no future tenant would either.

It would just keep on going.

Retaliatory Termination under RTA is a punishable offence, back then a $4,000 fine. Now $6,500

Landlord Disconnecting Services to a Tenanted Property? Well, that's a fine of $2,000 - per offense.

That was just the start.

The hearing didn't go well for him.

On a side note..The healthy homes amendments are about protecting ignorant tenants from exploitation by slumlords, not make landlords lives difficult.

I don't have a heat pump installed in my rental, breaching RTA however it's well insulated, warm, and I've offered to put one in but the tenant of 9yrs said don't worry about it.

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#2963218 5-Sep-2022 06:27

@K8Toledo interested to hear more of that story, how it went for the landlord!

K8Toledo

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#2963763 6-Sep-2022 02:05

timmmay:

@K8Toledo interested to hear more of that story, how it went for the landlord!

I went on a little rant there sorry.:D

From memory the landlord came away ~$8,000 out of pocket. AFAIK the place hasn't been rented since, the work required to meet compliance was cost prohibitive.

We then had an understanding that if I got wind there were tenants downstairs he would be prosecuted. It's a small town. :)

It happened about 5yrs ago, right after the new laws came into effect.

With newly increased powers of enforcement and heavier penalties the Tribunal were probably having the time of their lives. Seemed there was a crackdown for a while..

My parents didn't support me at all - "why bother go through all this trouble - you're moving out anyway?".-Mum Sadly also a landlord. :)

Back OT:

@everyone do people know about this Warmer Kiwi Homes grant?

It ends next year and the eligibility requirements are few. A friend in Wellsford had underfloor insulation installed for less than $100.

Ironically not available to landlords.

Warmer Kiwi Homes

mattenz

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#2963840 6-Sep-2022 11:32

Did he try and spin the old "we're flatmates" defense?

If you can get the grant, you probably should.

neb

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#2963960 6-Sep-2022 18:20

Wiping the affected areas down the BZK, benzalkonium chloride, will go a long way towards controlling mould, as long as it's not washed off later on. Unlike virtually everything else that's sold for dealing with mould, BZK is a fungicide that will kill the stuff and help prevent it from coming back. You can buy it as one of the 30-second mould killer brands in 3L or 5L concentrate form at places like Bunnings and M10, just make sure it says benzalkonium chloride on the container because virtually all other "mould removers" are just dilute bleach.

gzt

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#2963962 6-Sep-2022 18:35

Thanks for the tip. Is that suitable for fabric and synthetic blinds?

kiwirock

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#2963972 6-Sep-2022 19:25

mattenz:

I wish that we could stop calling PPV systems 'HRV'.

Sales people be sales people, confusion marketing tools. :) "Balanced" ventilation with an actual heat exchanger ('h'eat 'r'ecovery 'v'entilation) is certainly the bees knees all seasons.

I would argue to others that suggest not using PPV units it as much during the night in winter, that's when they're almost needed the most if your heat source drops for the night. In saying that, we don't have either. Heatpump stays on minimum 13 over night or when no one home, windows are cracked open in the morning and kitchen fan put on high to draw fresh air in during breaky, and all locked back up for the day.

Moving from a piled house with polyethylene ground sheeting to slab was the difference between mold and no mold for us. Both double layered roof insulation, reflective insulation under the piled house. Both places bathroom windows open a crack for faster return air for the extractor when in use.

I think a balanced HRV would hardly ever have to run where we are now. Maybe 5 minutes an hour over night if needed just to keep co2 down for a more comfy sleep in the smaller bedrooms (that's if the neighbours aren't one of those that don't know how to burn a fire hot and clean rather than smoky/wasted fuel).

timmmay

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#2963982 6-Sep-2022 19:46

kiwirock:

I would argue to others that suggest not using PPV units it as much during the night in winter, that's when they're almost needed the most if your heat source drops for the night. In saying that, we don't have either. Heatpump stays on minimum 13 over night or when no one home, windows are cracked open in the morning and kitchen fan put on high to draw fresh air in during breaky, and all locked back up for the day.

Moving from a piled house with polyethylene ground sheeting to slab was the difference between mold and no mold for us. Both double layered roof insulation, reflective insulation under the piled house. Both places bathroom windows open a crack for faster return air for the extractor when in use.

I think a balanced HRV would hardly ever have to run where we are now. Maybe 5 minutes an hour over night if needed just to keep co2 down for a more comfy sleep in the smaller bedrooms (that's if the neighbours aren't one of those that don't know how to burn a fire hot and clean rather than smoky/wasted fuel).

We keep the ducted heat pump on 19 when it's a cold day like today and no-one is home. I slowly ramp the lounge temperature so it's 24 degrees by the time we want to be in there. All heat pumps thermostats are different though - 21 degrees on the kitchen heat pump feels similar to 24 on the ducted.

We use a PPV system on a timer. During a warm time of the day ventilation comes on, ducted heat pump goes into "fan" mode, and I crack the uPVC windows so it blows air out of the house at the same time fresh filtered air is coming in. Plus we run the system other times as well, but not much at night. It works fine if your house has good extraction and doesn't get too moist.

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