Damp patches

hermum

I have problems with damp coming through my walls. I know that some of the render has blown but one huge patch is where previous owners had re-rendered. I've just noticed that the front of the house is also very damp & just gone out to check it & there's a pretty big crack that was covered with paint, might have been filled but too high up to check.
I know that I won't get a proper answer without having a builder in but am panicing about costs.
It's a Victorian house, originally 2 up 2 down with a utility & bathroom single storey extention. Which will make scaffolding tricky. Would it be best to take off all the render & start from fresh or knock back the damaged? Any idea of approximate costs? If necessary I would do the taking off the old to keep the costs down.

hermum

Anyone, please??

[Deleted User]

Hi,

when I saw the thread title, I was gonna suggest Tena Lady, but, not much help I suppose.

iamcornholio

If render is blown, then water gets trapped behind it and can't dry out. Patch repairing one or a few places only works as long as it really is just those few places which require repairing.

If the render is significantly in need of repair (blown/hollow/loose/soft/chipped etc), then you have to renew it all. But cracks on their own can often be sucessfully filled and that will be sufficient

But first you need to determine if blown render is really the cause of the internal problems

hermum

iamcornholio wrote: »

If render is blown, then water gets trapped behind it and can't dry out. Patch repairing one or a few places only works as long as it really is just those few places which require repairing.

If the render is significantly in need of repair (blown/hollow/loose/soft/chipped etc), then you have to renew it all. But cracks on their own can often be sucessfully filled and that will be sufficient

But first you need to determine if blown render is really the cause of the internal problems

Sorry for sounding dense but how do I do determine the cause? The front hopefully may get away with filling, as the damp is in line with the cracks initially until it soaks down almost the entire wall. Hopefully filling will work.
The side wall a lot of the render is damaged there's no window on the wall downstairs & it start a couple of feet away from the external door.

hermum

[Deleted User] wrote:

Hi,

when I saw the thread title, I was gonna suggest Tena Lady, but, not much help I suppose.

& probably more expensive than re-rendering

iamcornholio

hermum wrote: »

how do I do determine the cause?

You either investigate yourself, or get someone more experienced to have a look

Essentially, you look for obvious signs of defective render either just outside or above of the damp location. Dripping gutters, and cills wont help, but you are looking for defective render, and also defective paint.

But what I meant was - you need to determine if penetrating damp is the problem, and not something else such as localised condensation or rising dampness

If the damp problem is localised, and related to defective render, then just doing that repair will suffice in the short term, but if the rest of the render is on it's way out, then you need to plan for more extensive work in the near future

You may want to get some local quotes, but remember that the contractor will probably make things sound a bit worse as he obviously wants the work. So if you do get some builders/plasterers around to quote, listen carefully to their comments to work out which are being realistic and which are possibly over-stating any problems

hermum

Hi, Thanks, it's definitely damp not condensation & it's starting at the top of the wall-I'm not swimming so guess & hope it isn't rising damp.
I can see that the rendering has bubbled & in places has come off. It does look as though previous owners have tried weatherproofing by re-rendering patches, badly. Is this an incredibly expensive job? I'll do as much prep as I can.