problem with black mould building up walls, ceiling

starlight09

Mick,
Thank you for all that info, especially as you have one yourself. How do you measure the airtightness in the house, this I would like to understand more.

starlight09

gsxr1 wrote: »

yeah have to agree. The HRV systems are very impressive. The quality of the air in the home is noticeable fresh, balanced and pleasant . A house I once built had it and I noticed the need for plenty of attic space for the ducting. It all looked very expensive to install in a new home. I would expect it would even more expensive to fit into a completed home.

Dont know the price yet but I will definitely make a phone call to the company plus find out if it can be installed into my 20yr old house

MicktheMan

starlight09 wrote: »

Mick,
How do you measure the airtightness in the house, this I would like to understand more.

With a calibrated blower door system.
In a nutshell, a large calibrated fan(s) is fitted to one of the external doors. This fan(s) is used to pressurize/depressurize the building to different pressures and the air flow through the fan is measured. These measurements plus the geometry of the building are used to calculate the air tightness. The test is quantitative and repeatable and takes a couple of hours to do (there can be a bit of preparity work). Imo, this should be one of the first tests done where there are poor air quality issues in a home. You can pm me if you need more detail.

brendankelly

It is a pity you are so far away from me. I need to skim just one wall with about 5mm of lime putty just to see how much of a difference this will make. I am sorry I cannot be of any help to you.

regards Brendan

trixyben

just been looking at an extractor type van called the drimaster, think it sits in your roof space and an extractor van is installed in your landing ceiling, it has senors when it senses high humidity it sends clean filtered airflow through the house, seems a good product seems to be around €700 installed, i need something quick as i think its getting worst.

starlight09

MicktheMan wrote: »

With a calibrated blower door system.
In a nutshell, a large calibrated fan(s) is fitted to one of the external doors. This fan(s) is used to pressurize/depressurize the building to different pressures and the air flow through the fan is measured. These measurements plus the geometry of the building are used to calculate the air tightness. The test is quantitative and repeatable and takes a couple of hours to do (there can be a bit of preparity work). Imo, this should be one of the first tests done where there are poor air quality issues in a home. You can pm me if you need more detail.

Thanks Mick for all that.
You mentioned earlier that the HRV works in the right situations, Mick would it help to keep mould away, some of our walls are badly affected. I imagine it would.

starlight09

trixyben wrote: »

just been looking at an extractor type van called the drimaster, think it sits in your roof space and an extractor van is installed in your landing ceiling, it has senors when it senses high humidity it sends clean filtered airflow through the house, seems a good product seems to be around €700 installed, i need something quick as i think its getting worst.

I've been looking at that also and considering it but the thing is, it is placed in the landing and from that I understand that I would have to let all room doors open especially where there is steam or condensation for it to reach the fan, sure that's just taking the condensation all over the place, wouldn't a fan in each place be better. I have decided against it.

starlight09

brendankelly wrote: »

It is a pity you are so far away from me. I need to skim just one wall with about 5mm of lime putty just to see how much of a difference this will make. I am sorry I cannot be of any help to you.

regards Brendan

Thanks Brendan and good luck with it.

howtomake

I know this thread is a couple of months old. Have black mold (spots) underneath the vent in bedroom. Normally the windows are opened for awhile and it usually feels like there is a draft going through the room, even when the windows are closed, it is actually the coldest room in the apartment (which was very annoying this winter). Any suggestions, I can understand if it was the bathroom.

AMG86

The mould is due to condensation over a period of time. Have a look at this link. http://www.proair.ie/index.php?optio...=63&Itemid=209. Installation of a HRV system could go some way in solving your problem.


Look at Micktheman’s post of 30/01/11 in this thread. He is also suggesting the installation of a HRV system. This will most likely keep it under control. Of course if the build were done correctly day 1 you would not have this problem. It could be difficult to get rid of the cold bridge at this stage.

hucklebuck

Hi folks,

I live in a two bed townhouse and the two bedrooms are located at the front and back of the house, both of these get brown/black spots on the ceiling where it meets the external wall.

We dry clothes in the front room and the problem is not as bad there(this room has two windows, the other room has one), there have been cold nights where I have woken up to the sound of dripping water. This is where the condensation on the window has gathered as water on the sill and this is dripping onto the carpet. I know in my dads father's house there is a little tray with holes in it at the bottom of the window where the condensation can gather. I used bleach and this cleaned the mould off, the plaster underneath looks fine.

I went up to the attic and noticed the insulation is all the way across the joists and it is dry over where the mould forms, I remember hearing before that you should stop short of where the joists meet the rafters to allow ventilation. As the problem is the same spot in both rooms and does affect the downstairs rooms I was thinking of trimming the insulation in the attic by 6 inches on each side which would give more ventilation in the attic and which I hope should stop the mould in the bedrooms. A few of my neighbours have put vents in but they are unsightly and I am a light sleeper so wind whistling through the room would wake me.

Is trimming the insulation worth a shot? Both rooms heat very well and hold the heat.

Thanks

MicktheMan

hucklebuck wrote: »

Is trimming the insulation worth a shot? Both rooms heat very well and hold the heat.

Thanks

If you dont have a condensation issue in you attic space then, no, trimming the insulation as you call it will not help. Does the fibre insulation go all the way to the wall plate? If not, then add some but make sure you leave a 50mm air gap between the top of the insulation and the roof felt.
The attic space is a seperate space to your internal living space from a ventilation point of view.

You have excessive moisture build up in your living space which needs to be ventilated to the outside especially in the winter months. Drying clothes indoors doesn't help and just because you dont have the problem as much in the room where the clothes are dried does not mean that this activity is not compounding the problem.
Essentially, normal daily activities (cooking, washing, breathing, drying clothes) add moisture to the internal air (think up to 10 liters per day for a family of five) and this moisture needs to be constantly vented to the outside. Make sure you extact the vapour at source (extraction fans) open window and close bathroom door when showering etc, cross ventilate regularly and if you must dry clothes then do this in the coolest part of the house with the windoe open and door closed.
There are other ways to ventilate as well and these solutions would depend on the layout, budget etc.

Above is based on information given, is my opinion based on professional experience of investigating similar problems and assumes there are no other moisture sources in the building (leaks).
Hope this helps, Mick

hucklebuck

MicktheMan wrote: »

If you dont have a condensation issue in you attic space then, no, trimming the insulation as you call it will not help. Does the fibre insulation go all the way to the wall plate? If not, then add some but make sure you leave a 50mm air gap between the top of the insulation and the roof felt.
The attic space is a seperate space to your internal living space from a ventilation point of view.

You have excessive moisture build up in your living space which needs to be ventilated to the outside especially in the winter months. Drying clothes indoors doesn't help and just because you dont have the problem as much in the room where the clothes are dried does not mean that this activity is not compounding the problem.
Essentially, normal daily activities (cooking, washing, breathing, drying clothes) add moisture to the internal air (think up to 10 liters per day for a family of five) and this moisture needs to be constantly vented to the outside. Make sure you extact the vapour at source (extraction fans) open window and close bathroom door when showering etc, cross ventilate regularly and if you must dry clothes then do this in the coolest part of the house with the windoe open and door closed.
There are other ways to ventilate as well and these solutions would depend on the layout, budget etc.

Above is based on information given, is my opinion based on professional experience of investigating similar problems and assumes there are no other moisture sources in the building (leaks).
Hope this helps, Mick

Thanks Mick,

The insulation in the attic runs from wall to wall so there is no gap between the wall and the end of the insulation, that is why I was thinking of cutting the end of the insulation to leave a gap to see if that helped.

A vent would look unsightly, would it be an option to put a vent in the celing? I would put it beside where the mould is forming and this would allow the heat out and cool air in.

MicktheMan

hucklebuck wrote: »

A vent would look unsightly, would it be an option to put a vent in the celing? I would put it beside where the mould is forming and this would allow the heat out and cool air in.

You should look at the cause, not the sympton as explained in the earlier post.

M007

Anyone got the names of a good bleach/cleaner to get rid of mould on walls?

Have a lot of mould building up around windows - also spots developing on ceiling in bedroom. Will investigate the attic to see if there is a reason up there but at this point in time really want to try and get rid of the spots on wall beside windows.

Thanks

M