Mouldy wall -what to do?

[JoceAndChris]

This is the wall outside our London flat, in a Conservation area of Highgate, which I've been painting annually with exterior paint for years. I'm not really too sure of its age as our flat used to be the servants' quarters for the building but was converted in the 80s, so guess the walls are either late Viccy or 1980s :?

It's the view from the sitting room, so the impact on desirability is high- having said that the flat gets snapped up time after time and this year we've had just one day between changeover of tenants to sort the place out.

It's basementy at the front but the back is higher and leads into the entire garden for the whole 5 storey building, which belongs to just our flat. This garden sells the flat really, but still, I'd like to improve this front patio area. The sunken walls are severely damp and support the paved bin cupboard area at the front of the property, so we need them to survive!

Rather than repainting again this summer, would it be better to Klingstrip off all the paint and have bare brick? Is that something that would need permission in a Conservation area where white paint has been insisted upon?

Would limewash have less green mould after a year?

Thanks for your learned opinions, as ever.

 

[Feltwell]

I suspect bare brick would show any mould a lot less, but it would also mean the flat feels darker - much less reflected light.

Did you treat the walls with fungicide prior to painting?

http://www.rawlinspaints.com/p384/Sandtex-Trade-Fungicide/product_info.html

 

[JoceAndChris]

Thanks Feltwell - Good point regarding light. I didn't treat the walls with fungicide as the paint said it contained fungicide- wonder if that would make a difference?

 

[Feltwell]

I think you're supposed to treat the wall prior to painting if there is any growth, regardless of what the paint contains.

Very limited experience, but I treated a rather mouldy wall on a previous house with this stuff prior to repainting (with modern masonry paint - it was a modern house) - and when we left 3 years later nothing had regrown. That wall would have been drier than yours though.

 

[JoceAndChris]

Thanks Feltwell, useful.
I'm still tempted to strip it though.

 

[MdB]

A modern wall would have to be built with weep holes in it as potentially too much water could be trapped behind it. I guess an old wall like that would have less of an issue as the bricks / mortar would be more porous giving you the damp wall you have. Weep holes may be an idea though to allow more water to come through and allow your wall to dry out more. They wouldn't look great though.

 

[Feltwell]

Weep holes won't stop a wall being damp, they are there to stop the water from collecting behind the wall and the soil becoming saturated - the build-up of hydrostatic pressure can be quite dangerous and can push walls over. They're nothing fancy, in Civil Engineering structures they're generally just plastic pipe, rather like 32mm domestic waste pipe, running through concrete retaining walls and bridge abutments.

For a domestic brick wall a few small holes drilled through the mortar will do fine. It wouldn't hurt to do this and it will be unobtrusive, but I'm not sure it will make much difference to damp - the soil behind will still be damp, just not saturated.

Joce, even if you're stripping the paint off ( which won't be a pleasant or quick job) I'd still use fungicide first before doing anything, even brushing the walls, just to make sure that whatever is there is killed off.

 

[Gareth Hughes]

What about painting it with a nice yellow, and then applique-ing a Georgian print-room effect over it? :wink:

 

[jocelyn plummer]

Lovely flat Joce!

 

[FamilyWiggs]

Lovely flat Joce!

From what I gather from the limited photograhic evidence available, it is sometime since anyone called her that!

 

[JoceAndChris]

What about painting it with a nice yellow, and then applique-ing a Georgian print-room effect over it? :wink:

:lol: Or a shell grotto? With mossy statues?

Lovely flat Joce!

From what I gather from the limited photograhic evidence available, it is sometime since anyone called her that!

:lol: Unfortunately that is the case!

And thanks for the nice comment Joss - we felt very limited there in the end, but we did what we could with it in an eight year labour of love - removing the concreted garden, putting a new kitchen, bathroom etc. I'd love it as a pied a terre but funds won't allow!
Few more pics...

Feltwell, and MdB, thanks very much indeed for the advice regarding weepholes and paint. There is a little pipe in there that dribbles water onto the patio but more, little, discreet holes might improve matters. I will treat with fungicide when I go back. You've put me off stripping it a bit, I could only give 2-3 days to this - the cost of going there is about £60 a day for the train and tube. Oh, difficult to know what to do. It never seems to be empty for a good long period.

 

[Feltwell]

Oh, difficult to know what to do. It never seems to be empty for a good long period.

In which case, dare I say are you trying to fix a problem which does not exist?

The problem is the mouldy wall putting potential tenants off, not the wall itself. It clearly isn't doing this. I know it will be hard, but you need to think of the place in a business context, not as your home. Sorry if that's being patronising, it's not meant to be.

I appreciate that you want to keep the place in good order but it sounds like a single day trip to put some fungicidal wash on the wall and drill a few extra weep holes will be more than sufficient for now - the problem is cosmetic rather than structural. You can always give it a lick of paint before the next tenancy or before selling, should you ever decide to do so.

Stripping the paint off will be a very messy job. Ask PFord!

 

[JoceAndChris]

Not patronising at all - really appreciate it. You're right that it doesn't seem to be putting anyone off.

I suppose I have been concerned that by just repainting the damp wall every year I'm trapping moisture and eventually it will just crumble and collapse. The soil behind is very clay, so I guess if that happened the wall could just be built again against the solid clay?

It always amazes me that things don't collapse, even when they appear very damp . And weep holes would make some difference.

 

[Feltwell]

If the wall is not showing any signs of distress then I wouldn't worry - by distress I mean things such as the surface of the bricks flaking off ("spalling"). The wall being damp isn't really a problem - if it was then all our cellar walls would be well & truly shot by now!

It's the damp freezing and thawing repeatedly that would cause it damage - but that spot looks quite sheltered and the soil behind the wall will be acting as a heat sink. A wall built to retain soil will nearly always be damp, it's pretty much inevitable. Just keep an eye on the top of the wall, that's the most likely spot to eventually need work. From your pictures it all looks pretty sound though, given that the wall is at least 30 years old and more likely over 100 years old and has probably been painted in impermable paints for the last 30 years then I wouldn't worry.

If you've already got a pipe coming out of the wall that dribbles water then that sounds like it's doing it's job. Just bear in mind that any extra holes will cause a little run of water down the brickwork below, causing a stain, so keep them low.

Lovely building by the way - but then you know I've got a definite weakness for Victorian buildings!

 

[JoceAndChris]

Thanks Feltwell for that most reassuring of posts! In that case I will stop worrying about it, and plan just one day in London for a fungicidal wash and repaint with exterior white.

Your help is much appreciated. xxx

 

[JoceAndChris]

Lovely building by the way - but then you know I've got a definite weakness for Victorian buildings!

Oh, me too. I love that Dutch-style grandeur of the turrets and swooshes. 4 bed house in that street = 1.6 million. :shock: :shock: :shock: (Our flat is a tiny fraction of that size, I hasten to add!)

 

[CatherineB]

I agree with Feltwell, in that if you're only repainting to make it look nicer for tenants, why bother? If they're snapping it up anyway, let them, and then if a sitting tenant asks to have the wall painted you can go and do it. Or maybe they'll offer to do it themselves.

 

[Feltwell]

Thanks Feltwell for that most reassuring of posts! In that case I will stop worrying about it, and plan just one day in London for a fungicidal wash and repaint with exterior white.

Your help is much appreciated. xxx

No problem. Not sure you'd do that in 1 day though - the wall needs to be completely dry after the fungicidal wash, I would normally leave it 24 hours in good dry conditions before painting. Personally, from the look of the pictures, I'd just give it the wash and not bother repainting for now, it doesn't look that bad. Catherine's post is pertinent too, if you're happy for tenants to do it themselves.

 

[JoceAndChris]

I agree with Feltwell, in that if you're only repainting to make it look nicer for tenants, why bother? If they're snapping it up anyway, let them, and then if a sitting tenant asks to have the wall painted you can go and do it. Or maybe they'll offer to do it themselves.

Nice idea, but in my experience allowing tenants to manage the gradual deterioration of the property is a bad idea. I make a point of making a change for the better to that flat every year, whether they ask for it or not. Last year they had a lovely new sitting room door, the year before a new carpet. We are buying some new garden furniture for them and getting the pond professionally maintained. None of these things were asked for but at £50 a day I feel I have to make sure standards are kept high and tenants, who typically have stressful jobs (next pair are doctor and nurse) are looked after. This perfectionist approach means I have quite a lot of hassle and expense with it all but the flat gets snapped up time after time and my reputation is good.

I would normally leave it 24 hours in good dry conditions before painting.

Ah, OK, I am again being too ambitious then. I'll have to come over a period of 2 or 3 days.
Thanks for the warning.

 

[Feltwell]

£50 a day

£1500 a month? :shock:

Don't get me wrong, I'm sure you only charge the going rate, but by'eck that's a lot of money to rent a flat. London never ceases to shock me with it's expense compared to the rest of the country! While there's folks willing to pay it though........