Problems with fungus on kitchen wall

We have owned our house for 6 years and lived in it permanently for 5, last year in the summer fungus appeared on one end of the wall in the kitchen cleaned it off with bleach and water only to return and get worse, it is only from the worktop upwards.

We had an expertise out to look at it and he said it was not water in the wall causing the problem but because the house was too air tight and we needed to install a machine in the loft to purify the air at a cost of 5000 euros not possible as we dont have that kind of money to spend. We also had 2 people to have a look at the roof they said no problem there.

Has anyone any ideas on how to solve the problem or who to ask to come and have a look at it i.e. builder or someone with a machine that tests the wall for water.

Please any help or advice really appreciated as it is getting worse and dont want it to cause major problems that we cannot afford to get fixed.

Thanks Vic will have a read, not given up just a bit despondant. But as they say onwards and upwards.

Margaret. I,m sorry that my response to Mr Goddards "pah"ing!! has derailed your search for a solution to your damp problem. I can,t help you with a product to kill the mould but do seriously commend you to read the "Building Research Institute " publications you will find if you click on the link I previously indicated. Positive ventilation is an excellent & cheap solution in many cases such as yours. I have proved beyond doubt it,s efficacy in properties I own(ed), but as usual it does depend on the layout of the property.

If you have a roofspace, which is joined by a landing, which in turn is joined via the staircase to the ground floor rooms ( & in your case the kitchen assuming doors open) it can work well with negligeable running costs.

Have a look. What can you lose?

Once again thank you for all of your comments and advice soooo very kind I did not mean to cause disharmony amongst anyone.

If we have ascertained that it is condensation and not anything else and do the correct thing to correct this how do I proceed with getting rid of the spores, reading many articles on this that say the fungus are living spores and can multiply at an alarming rate before your eyes. Some comment that the only way to eradicate them is to strip the wall back to the original brick/stone and get an expert in to kill them with special chemicals. Surely there is something I can do myself to stop them growing this is purely for financial reasons that I have to try to deal with this myself.

Just in case anyone is thinking why cant my OH do this the reason is he has a broken neck and obviously lifting, stretching etc. is not an option and if I can solve this sooner rather than later would make me very happy.

Thank you Vic!

Mrs Higginson x

I,m sorry Ms Higginson if my post appeared personal. It was certainly not intended that way! I was always tought it was "bad form" to rubbish anothers professional opinion & I guess that even though I,m retired I still hold dear the principles I lived by in business.

My sole aim was to try to assist with the original problem & this is difficult if one,s opinions are being rubbished.


Calm down guys! And remember - this is not personal and please keep it that way.


Have you actualy read the information on positive ventilation or are you baseing your reply on something you say you did 30 years ago?

I have given an honest opinion & sadly have no wish to debate the subject further with somebody as angry & rude as you appear.

Have a look at this Mr Goddard. It may change your mind re. "attic fans".

It,s a different mindset but I can assure you, as a retired professionel building services design engineer, it is very often a good & ecconomic solution. It is of course difficult to diagnose problems like this at a distance, but given that the fungus appears above the kitchen worktop, on a north facing wall, in what appears to be a relatively sealed environment my immediate diagnosis is condensation.

Yes Mark the wall is North facing. Where do I get active sealer and do you know the name of it? and is it to use on the wall inside the kitchen.

Is the wall North facing? Below ground in any of its length? Dependant on the age of the property the mortar, render, plaster mix could have been made with water left for a few weeks in a large container/Vat. Dont panic no great expense use a propriety active sealer- within its makeup is usually an active herbi and fungicide. Some years ago I had a similar problem comments re ventilation are relevant but the active spores and their proliferation are the first point to be negated.

Try Googleing "Positive Ventilation"

It,s a relatively cheap solution which normally requires little building work.

It worked for me in my last french house & now works well in my mother in law,s stone built house in England.

good luck


The bleach can clean the mould but not kill it. Try using clove oil mixed in water.
It will keep it mould free for longer if it is ventilation problem.
I doubted this until I used it on ceilings in tropical Queensland bathrooms.
I redo the ceilings with the oil mix and a clean mop whenever the mould regrows - 12 months or more.

Hello Margaret

We solved our problem of mould on our walls by fitting trickle vents to most doors and windows. The vents allow a small amount of airflow from outside and can be also be temporarily closed if required. They are relatively cheap and easy to fit by a competent DIY'er To clean the walls I used a Mould and Mildew Cleaner, which did a good if not 100% job of removing it, and inhibits regrowth. The combination worked well for us.

Good luck

I would like to say a big thank you to you all for your advice and kindness in trying to help with this.

We will get another roofer out to check the roof again before trying anything else.

Great, we're making progress.


it could be lack of air ingress due to new doors.

It could be water ingress from the roof

If the mold is near the corner pointing, then it could well be that, but any water entering the first layer of wall should run down the cavity and out of weep holes at the base.

First job, wait until it rains and then get up in the loft and expose the area closest to the mold, see if there's any ingress.

If you don't have any ingress there. Clean up the mold as best you can and install an intake air vent and a higher level extract vent.

Use quality controllable air vents. If you have a woodburner or a fire, try to install the intake vents nearby as it'll provide fresh air without dragging air through the envelope.

I'd say it's either water ingress from the roof or lack of air intake from the new doors.

Bon chance!

Dear Margaret,

Damp problems can be quite complex and often there is no quick fix answer since it greatly depends on the construction of the building. Nick is quite right in that he says that ventilation is absolutely necessary. However you might not want to open your kitchen window in the middle of the winter and it is here that the problems start. You need a constant form of ventilation which as you have found can be expensive if it is mechanical. In a kitchen the humidity can be very high as in a bathroom. Without looking at the construction of your building it is likely that you have no insulation on that wall and added to this it is painted with a plastic paint which cannot breath hence the condensation etc. If it is an outside wall and made of stone you could make a big difference by insulating it on the inside but also using a vapour barrier so that no water vapour can reach the wall from the inside. Note that a 50cm stone wall has virtually no thermal resistance. In short your problem is a combination of lack of ventilation and lack of insulation. So don't go out and buy kit but go to the root cause.

Hope this is of some help.

Hi Henry

Answers to your questions:

1. The only vents are in the top of the kitchen windows and one window in the loungs.

2. We have had a new front door, patio doors and é sets of double door upstairs in the bedroom no air vents.

3. No changes externally.

4. Yes they are.

5. The gutters were cleaned this summer.

6. The mould is from the start of the worktop to the kitchen ceiling.

It has been pouring today and there is much more water in the dehumidifier.

I am really not sure if I truly believe that there is not a problem with the roof.

We have decorative stone edging running up the 4 corners of the house, so a possible problem with the pointing?

Hi Margaret - having had this problem more than once (in our student house) - it's down to living, as simple as that!

We had a report on this, a few years ago, from someone that does these reports for a living, and no, we were not ripped off, he was recommended by someone very trustworthy, and we were told that the problem was simple - living!

We have just had our handy man putting in an airbrick in another room in thestudent house + a bit of decorating to make the wall look good again, and all is well, and again, our handy man is gold dust, he does not 'fix' anything that does not needs fixing, and he never ever rips us off either (wish we could take him with us to France when we hopefully move in there in the near future) - yes, indeed one of the old reliable kind which is a rarety these days!

You need to make sure that your doors inside as well as the front/back doors and windows open a regular basis, so there is an air flow though your house regularly, not just where the problem is. Be careful with mould, it's not healthy stuff! Do you have any air bricks?

We all live in such a 'warm' dobule/tripple glazed environment with our central heating or whatever heating we have, our carpets and the rest!

Wish you good luck, this should not cost very much to get fixed, but bleach will not do the job! :)

Here's a great article on mould: