Penetrating Damp? remedy

guppy

Sonofa wrote: »

I'm no bricklayer, but you should be able to determine the type of construction from the outside by looking at the brick pattern. Standard stretcher bond is where the bricks overlap above and below by half the length. This will be a cavity wall construction if the wall has any significant thickness. Should be immediately obvious by looking at the depth of the reveal to the window opening and how far in the window is set into the opening from the outside.

A solid wall construction will look the same with the exception that every fourth course will be bricks end on (headers?) so you are looking at their width by height rather than length by height. I think this tends to be about 9" (225mm) thick.

A third option would be a combination of the two where you don't have a complete course of headers, just one after every three, four (I'm guessing here) stretchers.

Paintpot,

Have a look at the pictures here http://en.wikipedia.org/wiki/Brickwork to see examples of what Sonofa is talking about.

paintpot

Hi

Thanks everyone for the help. I am attempting to post some links to one of the affected walls (hopefully). The damp runs between the two windows in the photos. The last picture shows how the decor was affected before the plaster was redone and shows the damp as a strip that is above the level of the render outside but it doesn't reach the ceiling. I think the wall is flemish bond possibly but it is quite hard to tell due to the render and masonry paint but I think I can see a combination of headers and stretchers. The photo does show the masonry paint deteroriating above the render. The mortar joints seem fine, I don't believe any cavity wall insulation has been put in (if indeed there are cavities). The building was converted into flats pre 1991/992 building regs and there has not been any building work done since then.

sooz

Paintpot - you've got a boiler there with an overflow. There is some staining under the overflow. Does water regularly overflow?

Is the boiler upstairs in the same position - or any other overflows coming out in that area? Perhaps a toilet one, with a ball thing (censor won't let me write that word) that gets stuck?

Are there any airbricks under that render, that shouldn't have been covered?

Atleast the inside is looking better than the picture in your first thread! Still not great though.

The interior pic - is that by the second larger UPVC window? The pointing to the side & the bottom of that window does look like it's been repaired by someone with a spoon. .

absolutebounder

Paint pot just a couple of ideas
1) is it getting in at the top of the rendering?
2) The boiler Does it plume and the plume blow back on to the walls. Im guessing its not a condensing boiler as I couldnt see a condensate pipe but boilers produce quite a bit of water in the form of condensation

ukmaggie45

The rendering looks strange to me, the way it's done - goes up one side of the window and not the other. And it's upper edge is not straight under the left window, so the whole thing isn't symmetrical. I wonder if the rendering (looks like over-painted pebble-dash?) was put there to cover up some fault?

I know nothing about building and stuff like that, only the small amount I have learnt from 35 years in the same terraced house. So feel free to ignore me, just saying what I noticed from your photos.

Good luck with sorting it out!

paintpot

Sooz, your comments did make me laugh :rotfl: Most of the render looks like it was applied by a blindfolded man with a spoon.

Whilst the render has been applied in a strange fashion:rolleyes: it is solid and adhered to the wall ie it isn't blown, cracked or falling off. I have always questioned why it only goes to that height and whether it was hiding something. No idea if there are air bricks behind it or not. I reckon it was done about 15 years ago, maybe more.

The windows are wooden single glazed not UPVC in that flat.

The boiler overflow was leaking back in April but was quickly repaired and I did at first wonder if that was the cause of the problem as it was leaking probably for quite a considerable period of time and wasn't reported by the previous delinquent tenant, hence the staining on the wall. However the worst damage to the masonry paint is the opposite end of the problem.

The boiler does plume out of the flue - could that really cause that amount of damage plus the damage is much lower than the flue and has spread quite along way from the flue but definitely an option? How would one remedy that then :rolleyes:

There is no boiler above, there is only the bathroom to another flat above the bedroom.

I can't remember what other pipes are immediately above, there could be an overflow from the toilet perhaps but you can see that there are waste pipes from the bathroom above the window.

The worst breakdown of the masonry paint is by the biggest window and you can see there is no pipework immediately above in the photo. Aso, I have looked and can't see any of the pipework leaking or the gutters spilling over.

Hence my penetrating damp theory. Could the bricks have become porous, anyone able to deduce whether the house has cavities or not from my pics?

Also remember I have a similar issue next door but on an upstairs bedroom wall.

Below is a picture of the two houses from the rear. As you look at the picture the house on the left is one with the ground floor damp issue and the house on the right has the damp on the wall where you can see what looks like a burglar alarm bellbox. If you look at the brickwork on the end wall particularly to the left of the upstairs window right at the back of the building it looks pretty cracked and blown to me. I also had the roof and the guttering looked.

Any more thoughts and theories appreciated.

mlz1413

In my house I have a patch of damp starting about 3' high and spreading up and outwards (it's about 6' wide and 3' high) it seems to magically start 3' up which most people would say is impossible.

We have found that when the house was DPC'd the plaster up to 3' high was replaced, being newer plaster it is doing a fine job of holding the damp back, but as the plaster above is old (also a victorian terrace) the damp is rampent.

My damp IS rising but it is caused by a garden wall that just touches my outer brickwall (it's an end of terrace at the top of the street, so the gardens from street above run down towards the house), irritatingly this has all be digisnosed by my partner who is a general builder - but had nothing done about it because he is a general builder and getting him to do a major job is like booking a unicorn.

Anyway personal stuff aside, I'd say get a general builder out to quote for remedial work to stop the damp, that should be free (its a quote) and should give you a idea of how it is happening and how they are going to put it right. I'd also ask if they won the job how long they would guarantee it for - should sort the cowboys out.

Good Luck.

paintpot

Thanks for that. My damp is above the render level so it seems that possibly the render is serving it's purpose by stopping damp getting in below. I have also stripped all the plaster off the wall which your normal type stuff which I don't believe is the right stuff for a property of this age and construction and then a specialist plaster supposedly to prevent damp coming through that had a 10 year guarantee on it - only that hasn't worked. :rolleyes: Which tells me it must be quite serious if the damp has managed to penetrate again this quickly.

The wall behind the boiler hasn't had any work done on it though and the plaster behind the pipes is crumbly so maybe damp from there is moving along the wall to the bedroom as the problem isn't as bad now as it was in the photo but given time probably will become so.

Would rendering higher possibly cure the problem or would that only exaserbate the problem further . I've read alot about wall treatments like coatings causing more harm than good as it it traps the damp inside so it can't escape.

I just don't want to make a bad problem worse.

I thought tanking might be an option but I believe that has its problems as well and it not always a long term solution.

Oh, which way to turn, I might just bring in the bulldozer :rotfl: