corner of parapet wall - water ingress

[lizziecupcakes]

Just incase it’s useful, this is a closer up photo of what if looked like before we purchased the house. The previous owner had the same water ingress issue but didn’t know the cause nor tried to fix it.

 

[Cubist]

That's pretty much what I'd concluded. The rain hopper is too low down the external wall to be the source of rain-water appearing where it is in the bedroom. The height of the damp patch indoors, in my estimation, broadly correlates with the with the top edge of the gutters or perhaps marginally higher. Also, I had not noticed before that both yours and your neighbours gutters halt near each side of the parapet wall and there is some kind of 'lip', perhaps made of lead or felt (?), intended to guide water from the upper face of the parapet toward the hopper below.

Some possibilities occur;

• I seem to recall you saying in an earlier post that your neighbours gutters were cleaned out shortly after you purchased the house. Sometimes the pipes from the gutter down to the hopper can become blocked with rubbish and in heavy rain the water in the gutter cannot escape fast enough and the dam at its end produces a cascade over its top. Both yours and your neighbours could be checked to see if theres a blockage on either side and perhaps also lower down through the pipe from the hopper to the ground.
• In heavy rain and windy conditions any water falling from that 'lip' in parapet could be driven against the wall behind.
• Whichever of the above your best approach would be to ensure that the render on the face and sides of the parapet wall is made good and at the same time examine and improve the pointing of the exposed brickwork behind and above the hopper.

 

[lizziecupcakes]

Thanks Cubist. The roofer sent a closer up photo too. It’s from about 9.30am today

Btw, by “lip” I think you mean the slate that sticks out? It’s slightly broken on our side (it was like that when we first viewed it too)

 

[lizziecupcakes]

I seem to recall you saying in an earlier post that your neighbours gutters were cleaned out shortly after you purchased the house. Sometimes the pipes from the gutter down to the hopper can become blocked with rubbish and in heavy rain the water in the gutter cannot escape fast enough and the dam at its end produces a cascade over its top. Both yours and your neighbours could be checked to see if theres a blockage on either side and perhaps also lower down through the pipe from the hopper to the ground.

The neighbour’s gutters were replaced last May - she installed new ones. They are normal sized ones (shallower), whereas ours are deeper. It is worth us checking if it’s trapped or over-spilling for sure! I don’t know why we didn’t think of this!

We experienced our own gutter poorly handle heavy rain a few months ago and saw with our own eyes water spill over onto the wall. This could be a potential cause if the mortar is already compromised.

In heavy rain and windy conditions any water falling from that 'lip' in parapet could be driven against the wall behind.

Ah, I see what you mean: so you mean water sitting on the slate could be driven into the wall during heavy rain. That is a possibility too!

 

[Cubist]

Damn my eyes! I didn't see that in your roofers photo of gutter and parapet that the end cap for the gutter is clearly leaking and nor did I see that the slate is damaged. Both of these could also be a source of the problem. The end-cap should be easy to stop it leaking but any overspill from the gutter may be a little more challenging. The slate on the other hand introduces another possibility inasmuch that it can sheer and split along its inner leafs (for want of a better word) and water can then track through between these to leak out further from the damage than you might expect. This may be a slim additional possibility but it could be worth considering.

 

[lizziecupcakes]

the end cap for the gutter is clearly leaking and nor did I see that the slate is damaged. Both of these could also be a source of the problem.

thanks Cubist, but I personally can’t see where the gutter is showing signs of leaking? Could you kindly point it, that would be so helpful to us

 

[lizziecupcakes]

Also, i found a photo from when we first viewed the property. The previous owner would just plaster over the patch and leave it. They said they didn’t know what the cause was. Weirdly, the darker shadow kind of looks like the shape we see when the rains are at their heaviest, but maybe I’m looking into it too much

 

[lizziecupcakes]

And this is the corner after we removed the old lime plaster and a few laths to get the insulation in above it.

 

[Cubist]

thanks Cubist, but I personally can’t see where the gutter is showing signs of leaking? Could you kindly point it, that would be so helpful to us

When I look just below the end of the gutter where it borders the brickwork of the parapet wall I can see a heavy stream of water droplets that appear to be coming from around the end-cap of the guttering and just above the pipe that feeds into the hopper.

 

[lizziecupcakes]

Thanks Cubist! I’ll keep this thread updated

 

[lizziecupcakes]

Hi all, does anyone know anyone that can do a partial re-render to our parapet wall ? Just the front corner. It’s currently made of cement render (plus little bit of sand and stones?).

I just want the portion that’s inline with our water ingress issue to be removed and then re-rendered and blended into the rest of the parapet wall.

I don’t know which professional to go to?

@Lacan07 do you have an idea in the kingston area?

Thank you