Serious Mould Problem

[Mshepp]

I am currently having a serious mould problem behind my sofa and was wondering whether I could pick some brains on the forum to help solve the cause.

I went to clean behind and underneath the sofa today but found a large amount of mould on the skirting and the wall itself. I re-caulked the skirting about two months ago and saw some minor mould when I did this but just cleaned it off and it was no problem. The amount I found today is in a completely different league. The paint has bubbles in it and is peeling away from the wall exposing the plaster itself, the plaster does not look wet or damp and is in no way discoloured.

I suspect the cause of this is lack of air circulation, the sofa is right up against the wall and we have put some pipe insulation under the sofa to prevent the draught that comes in, in retrospect may not a been a great idea. I'm hoping it is a simple matter of limited air flow and won't require any major work.

The whole ground floor has had a chemical injected damp course applied just under a year ago.

I've uploaded some pictures of the affected area. In the meantime I've put some pots of rice behind the sofa in the hope of extracting some moisture.

Thanks in advance.

 

[John D v2.0]

Yes must be stagnant air near a colder wall, the moisture in the air condenses out when it diffuses over there. Maybe the draught was drying it out before.
You can try the usual things, use fans when cooking/showering, ventilate daily, don't dry washing inside.

 

[endecotp]

The whole ground floor has had a chemical injected damp course applied just under a year ago.

What symptom was that intended to solve?
Did some "damp expert" convince you to part with lots of money because of "rising damp"?

 

[Mshepp]

What symptom was that intended to solve?
Did some "damp expert" convince you to part with lots of money because of "rising damp"?

I'm pretty sure this is what happened. We live in a semi built in around 1895 and the slate damp course had apparently been breached. In fairness there was damp up the wall, to about 1m, that was causing the wallpaper to peel of and a lot, if not all, the plaster was blown.

 

[richw]

Out of interest, why not simply call the damp-proof firm back as ask them to explain? I wouldn't mention the soft, and move the pipe wrap!

 

[Mikefromlondon]

It is essential that before you do anything to clean this mold, you need to kill its pores so that they don't settle in a damp place again and start breeding again, I tackled such problem using strong bleach (domestos) and applied in strong concentration, not a weak, all over the damp wall, until all mold was killed and then using clean towel, dried the wall and allowed it to dry for 2 to 3 days using just cold air blown by a fan, (when i mop my workshop floor, it takes 20 minutes to dry when my garden door is closed, even though i have like 21 - 23 deg indoor temperature, but as soon as I open the door, some cold draft will come in, but dries my floor in less than 5 minutes) it is not the heat that dries but the flow of air that dries my floor in 5 minutes) so yes essentially a good air flow will remove moisture and take it away somewhere else, so you also need to ventilate to expel this damp air, also clean your floor with bleach as the mold pores could be all over the floor and carpet, so good vacuum all over, to speed up, you can use fan heater, but this will cost you a more in electricity, but will be much quicker, again don't allow the warm air laden with moisture from the wall to get in other rooms or areas of your house as the problem will simply shift somewhere else, so good ventilation to outside is essential when doing this.

After walls are dry, I painted an oil based white paint such as undercoat, this seals any pores still lingering about, and then when this is dry you do your normal emulsion and I have not had this problem reoccur again ever.

(Many things such as using bleach and sealing with oil based paint after drying may contradict opinions of professionals and what others might say, mine is a proved and tested method and has worked so well for me that mold has never come back.) but it also essential that your must change your life style and living habits such as not to dry your washing indoors and on CH radiators, when cooking , use extractor fan, after taking a shower or bath, keep the bathroom door closed and open bath window and ensure bath heater is on also, or you will get this in bathroom as well, I won't be surprised if you also have this mold in your bathroom and as well as kitchen in some spots, so you need to also air your house for about 15 minutes with all doors and windows open for about 10 to 15 minutes everyday, tw0 times if possible, place permanent vents for moist air to escape when CH is on. lots of things we do can cause such like problems, and also maintain gaps for air to circulate behind sofas, cupboards, beds, and other furniture.

I experienced this at a property I was put in charge for another landlady, and her tenants could not open the garden sliding door as they had lost the key, and the landlady did not have a spare key! so for much of the time the room had no other opening or windows except this sliding door, to air out moist air to the outside, the mold started and spread not only along the walls, but ceiling as well as her bed that was two feet away from the wall, and got hold on her duvet, and pillows! It was something from real hell!

in the end, all bedding's were thrown out, cupboards were also cleaned with bleach, there was also thick layer of mold (at least 3mm thick behind the cupboard lining, after cleaning with bleach it was also sealed with two coats of white undercoat, as far as i know it has not reoccurred. The door opens now and a permanent air brick has been installed in that room.

 

[vinn]

OP,
You have classic "Black Spot" condensation but there also appears to be salt signs from damp penetrations.
Is the wall in the pics Dot & Dabbed or solid plaster?
Did the D&T Co. use render or gypsum plaster on any walls?

Are the walls solid?
Is the floor solid? Is that a wood or vinyl floor covering?
Is the outside rendered?

FWIW: If you have children then keep them away from the mould/room.
Isolate or unplug the elec outlet - its at risk of arcing due to moisture in the box.