Leaky solid wall - to be expected?

[brummielad]

We have a Victorian semi, with an exposed SW-facing 9" rear wall, currently painted brick, although this is peeling in parts. We had 4m double-doors / windows put in (nearly full width), replacing small doors and window. When the opening was made and the steel put in, we noticed that rainwater was coming down the inside of the wall, and also seemed to be coming down the middle of the 'solid' wall, too.

(An aside: builder didn't use a cavity tray because it is supposedly solid, but since there's a gap of a few mm between the courses - aside from those bricks that tie them together - it doesn't seem solid to me, in terms of water anyway).

The job has been finished, and all small cracks that opened up externally above the steel have been filled; yet the leaks continue, with water evidently running down either the middle of the wall or the inside, hitting the steel and tracking inside (rather than out through weep holes drilled as an attempt to solve it). Windows on 1st floor and attic conversion have been replaced recently (PVC instead of rotting wood), and sealed properly I believe.

There were damp patches before the work was done (internal plaster on 1st floor, brickwork on ground floor to about 3ft), which suggests water was coming in and I guess could have been running to the floor unnoticed.

Final point: many of the houses in the road have had their rear walls pebble-dashed or rendered. The mortar is very soft.

My question: would it be considered normal for a wall of this type/age to let in so much water? Was that the design? Is it even feasible that repainting might solve the problem, or should I be considering render?

Apols for long post, any advice welcome, I'm struggling to get anywhere.

 

[stuart45]

9 inch walls were not designed to let in water. The idea was that some water would soak into the brickwork evenly over the wall, but it was thick enough for the water not to penetrate the interior. The water would then evaporate later into the outside.
As brickwork gets older and the joints become loose the wall can become more porous. When a wall is painted it can protect the brickwork, but when it peels it allows water back in. The problem can be made worse by the fact that the paint will hinder the evaporation and the wall stays wetter than without the paint.
It may pay you to re-point the wall first and then re-paint it. Once brickwork has been painted you are stuck with it.
The builder was correct about not using a tray, although weep holes are no use on a solid wall either.
Have you got any leaking gutters?

 

[brummielad]

Yes, the gutters are leaking a little, although not significantly. Do you think repointing and painting might solve it then? There really does seem to be quite a lot of water coming in - is this to be expected?!

 

[stuart45]

Fixing the leaking gutters and re-pointing should help. Paint with a micro porous paint which will allow the brickwork to breathe. Probably best to wait for the summer when the walls should be dryer.

 

[brummielad]

Thanks for the advice Stuart. That's interesting about the solid wall, I didn't realise they were built to work like that.

You're right, the wall is saturated now, so we'll keep the buckets on hand for a while longer. In terms of the microporous paint, would wirebrushing the old stuff and painting over be sufficient to get the benefit? I'm going to guess that the old stuff is unlikely to have been microporous.

One final qu: if we went the render route, would I be right in saying that we should get lime render, for the same breathable quality you recommend for the paint?

Thanks again for the help.

 

[stuart45]

I would think that most plasterers would recommend a sand/cement render with an added waterproofer to seal the wall.
Another place that can sometimes let in water is at the eaves. The felt here can become brittle and fail allowing any water which has penetrated the tiles and run down the felt to enter the top of the wall.
If you decide on he painting option I would take off as much of the old loose paint as possible.

 

[brummielad]

Thanks for the help, that gives us a few things to investigate.