Roofer or Plasterer or both?

[butchdingle]

PXL_20210121_184146407

• butchdingle
• 24 Jan 2021

Wall

Hi

I am after a bit of advice please

The attached wall image shows a damp patch we have in one of the rooms it first started about Sept 20 as a damp patch but over the last 5 months or so has become this.

a bit of background on the property

The property is an 1980s built house which is half brick/half rendering and this damp is about half way up the rendered part of the wall and half way across it.

We had Dry Verges fitted approx 15 months ago and recently had a two tiles replaced at the front of the property as they were broken, these were on the same wall as this damp stain but we have had no water damage from the broken tiles that i can see, but the wall is still getting wet where the staining is when it rains heavily/persistently.

In a similar position to the damp stain I can see a possibly brick length of mortar missing.

My question is this likely to be caused by the rendering, it doesn't look blown( but i am no expert) or the missing mortar or something else ?

The next part of my question is once the cause of the damp patch is identified and fixed and the wall dried out would this wall need reskimming or could it be taken back to the plaster(it seems to be only painted over and then wallpapered?

Thanks

 

[datarebal]

picture would help

 

[butchdingle]

Sorry thought it was added - hopefully there now

 

[datarebal]

yes

 

[butchdingle]

Sorry yes to now added or my question ?

 

[datarebal]

The picture is there .. it doesn't help much as it's a damp patch.
Ideally needs outside and roof picturesv

 

[butchdingle]

This is an outside view of the roof area with one the replaced tiles visible ,I will try and add a side view tomorrow in daylight showing the rendered wall and the wall above the rendering.

 

[catlad]

Is the damp patch on the side with the sky dish?

 

[butchdingle]

@catlad Yes its is

 

[^woody^]

It's a cavity wall, so defective render will not cause water to the internal leaf.

Any damp plaster will need to be completely removed and replaced, not just waited for it to dry.

 

[butchdingle]

It's a cavity wall, so defective render will not cause water to the internal leaf.

Any damp plaster will need to be completely removed and replaced, not just waited for it to dry.

sorry, so are you saying this has been caused by a leak in my roof or maybe an issue with the pointing around the brick work ?

 

[^woody^]

sorry, so are you saying this has been caused by a leak in my roof or maybe an issue with the pointing around the brick work ?

A cavity wall by design does not let water across. Therefore other causes should be investigated first

 

[butchdingle]

A cavity wall by design does not let water across. Therefore other causes should be investigated first

Is there a way I can check the Cavity myself or if say a roofer removed some tiles on that area of the roof would they be able to see down the Cavity?

Could it be being caused by missing mortar around the bricks in the proximity of the stain, thus when it rains the water is going down the cavity and hitting the inside wall or is it more than likely to be something else ?

 

[butchdingle]

Some shots of the outside wall taken this morning, the damp in the room is behind the sky dish at a similar height to it

 

[^woody^]

Water does not get across a cavity wall. It just doesn't.

If an internal wall is damp then its either getting damp from above or the cavity is bridged.

A cavity may get bridged when the wall is built, in which case the inside wall is damp from day one. If the damp is new then something new has happened to cause it

If the damp happened after the dish install, the dish bolts may be too long or the brick was broken when the fitter drilled the holes - causing a cavity bridge