White fluffy mould appearing on ext wall - photos.

seeing_ie

Hoping someone can point me in the right direction here.

This white fluffy mould, with speckles of the traditional darker mould patches, has started appearing on an exterior wall behind a toilet in a ground floor en-suite.

The wall was replastered about a year ago, the mould started appearing about 3 months ago.

Would appreciate info on what's the correct course of action to take.

seeing_ie

couple more photos here.

North West

Hi seeing ie
that looks like a fungal growth of some sort. Ring Protim Ireland they should be able to help you or direct you to who maybe able to help ?
NW

seeing_ie

North West wrote: »

Hi seeing ie
that looks like a fungal growth of some sort. Ring Protim Ireland they should be able to help you or direct you to who maybe able to help ?
NW

OK, anyone have time to outline how you'd deal with it yourself?

Or what exactly causes this usually?
Could there be a leak in pipes under the concrete behind the toilet?
Could it just be bad ventilation?
The wooden windows in the house were replaced with pvc framed (without built-in vents) a couple of years ago. As an old house it also doesn't have vents built into the wall of every room.

This problem only arose the first winter after the wall was replastered on the interior.
As an aside, I think a bad plastering job was done.
The wall is nowhere near smooth, and the metal cornerpiece surrounding the window that the plasterer put in (the piece to give the corner a clean edge, that's supposed to be under the plaster) is visible in places.

Thanks for reading folks.

Avns1s

The white "fluffy" mould as you call it looks to me like there is water coming from somewhere, either a pipe in the vicinity or ingress from outside.

The black mould is condensation caused by the temperature of the wall and less than ideal ventilation.

All in my own opinion of course.

CBYR1983

Looks like Saltpeter to me- could it be from the blockwork? Have you been living there long? Is there any dry lining on the wall?

seeing_ie

CBYR1983 wrote: »

Looks like Saltpeter to me- could it be from the blockwork? Have you been living there long? Is there any dry lining on the wall?

It's a 40 year old house, we've been there 20 years.
There's no dry lining on the wall in this ensuite, but there's dry lining on the same wall in the adjoining bedroom, and the wall of the bedroom next door.

I'm not explaining this too well, but the whole gable end of the bungalow, which is hit by the prevailing wind, was dry lined on the inside in the bedrooms about 10 years ago.


Please see attached photo of a similar-ish gable end:

The 2 white areas are the parts of the 2 bedroom walls which are drylined.
The ensuite between the two bedrooms wasn't dry lined.
The toilet in the ensuite is against the gable wall, roughly where the red square is in the photo, and the dampness is concentrated on the wall behind the toilet, mostly low down, just above the skirting boards.
There's a small window above the toilet in the gable wall.
There's no shower or anything to cause excessive dampness.

BryanF

you need a site visit - but start by looking behind the drylining

wayoutwest

But the O.P has said that there is'nt any dry lining in the en-suite room-maybe its a simply a cold bridging issue because of this
O.P - is their a radiator in the room and how often do you open the window?

seeing_ie

wayoutwest wrote: »

But the O.P has said that there is'nt any dry lining in the en-suite room

Exactly.

wayoutwest wrote: »

maybe its a simply a cold bridging issue because of this
O.P - is their a radiator in the room and how often do you open the window?

Yes, there's a radiator in the room. There's no shower in the room.
I'm told the window is open regularly (don't live there myself), as in left open a crack at night etc.

Just found out too that both bedrooms are dry lined along the sides of the house too, as well as the gable end.

BryanF

wayoutwest wrote: »

But the O.P has said that there is'nt any dry lining in the en-suite room-maybe its a simply a cold bridging issue because of this

perhaps i didn't explain myself - if its like this in a non-drylined area, it would be advisable to assess the wall condition behind the drylining elsewhere to ascertain the extent of the problem.

mould causes respiratory health issues, just because its not visible on the internal wall doesn't mean its not as serious

'cold bridges' hidden by dryining - where will the due point be? maybe have a read up on interstitial condensation..

O.P - is their a radiator in the room and how often do you open the window?

the ventilation is very possibly a factor but the skirting level mould would suggest its a penetrating damp issue aswell

I concur with northwest's company recommendation

BryanF

seeing_ie wrote: »

OK, anyone have time to outline how you'd deal with it yourself?

not trying to be smart but, there is nothing like a site visit to and a dig about to figure out the source. so the only advice i can offer is by process of elimination.

Or what exactly causes this usually?

1. lack of ventilation, cold surface temp due to lack of insulation(if single leaf, this should be external insulation) or lack of heating
2. leak, external render cracking
3. rising damp - change in external gl or water source
4. in old homes possibly a change in the breathable (hygroscopic) properties of the wall build-up

Could there be a leak in pipes under the concrete behind the toilet?

so get a moisture meter and assess floor/wall, internally and externally check for signs of leak

Could it just be bad ventilation?

is there no vent in the room, this will have some bearing, but the mould colour suggests additional moisture source - what is the cleanness of the house/bathroom generally like?

The wooden windows in the house were replaced with pvc framed (without built-in vents) a couple of years ago. As an old house it also doesn't have vents built into the wall of every room.

the pvc wins and/or additional insulation levels will alter the houses temp and air-tightness, and thus ability to expel humidity

This problem only arose the first winter after the wall was re-plastered on the interior.

now were getting somewhere - why was it re-plastered? what type of plaster was there originally and what type of wall build up is it. perhaps the original plaster was lime based?

As an aside, I think a bad plastering job was done.

this suggests to me that its about the wall structure/plaster coat and not solely ventilation

additional textthere appears to be earth up against the building?? this is potentially your problem! install a French drain and back fill with gravel for at least a ft around the house.
also dry-lining is a rubbish solution especially where there are underlining damp problems, consider cavity fill or EWI instead, and install room vents regardless! best of luck

roy rodgers

As a plumber it looks like rising damp from a leak under the floor.

I have seen many places like that from a leak.

seeing_ie

Appreciate the time taken with the replies folks, some good information there.
Don't have time to reply in detail just now.

dathi

the white "fluff" is not mold it is efflorescence, that is a build up of salt crystals as moisture evaporates from damp block work, check that you don't have a leak from any pipes in the area.

Hootanany

Protim have gone bang Pm me and will put you in touch with main guy that as with them.

TopTec

Hootanany wrote: »

Protim have gone bang Pm me and will put you in touch with main guy that as with them.

Wrong thread perhaps ? ;)

Hootanany

TopTec wrote: »

Wrong thread perhaps ? ;)

How is it

TopTec

Hootanany wrote: »

How is it

Whats efflorescence on brickwork got to do with "Protim" (whatever that is)? Or have I had a headrush and have missed something obvious?

Hootanany

Would you like to read the third post op:cool:

TopTec

Aaaahhhhhhhhhhhh! Now I get it!

My apologies. :o

TT

Hootanany

TopTec wrote: »

Aaaahhhhhhhhhhhh! Now I get it!

My apologies. :o

TT

No problem.

seeing_ie

Hootanany wrote: »

Protim have gone bang Pm me and will put you in touch with main guy that as with them.

PM sent, thanks for all the replies folks.

kieranhr

dathi wrote: »

the white "fluff" is not mold it is efflorescence, that is a build up of salt crystals as moisture evaporates from damp block work, check that you don't have a leak from any pipes in the area.

Probably too late now, but Dathi was right. It was efflorescence, or a washing through of salts.