corner of parapet wall - water ingress

[lizziecupcakes]

hi all
Unfortunately, the very heavy rainfall and high winds seem to have cause a leak in the corner of my bedroom (which i just had boarded and skimmed). it's not a terrible amount that I'm hoping will be ok once dried. It is drying too, since the rain stopped.

Our roofer came out to look at the area and he said the bitumen (breathable type) in the area is bone dry and the lead flashing seems absolutely fine. He said our new (deep) gutters seem fine too and there doesn't appear to be any overflow possible. He said he noted a lot of hairline cracks along the parapet wall (I'm waiting for the photo to be sent to me to share with you) and he thinks the high winds have forced the heavy rain into the cracks and it's soaked the brickwork/wall and that's seeped into the plaster a bit. I think it's likely this too, as our surveyor also mentioned cracks in the parapet wall before we bought the house. I think if it was the gutters, then it would have soaked the walls more.

I've attached a photo below from the day I discovered it - it's the bit in the curved ceiling part that alarmed me. The corner where the leak appears is at the junction between the parapet wall and roof (right in the corner). The section on the wall has been drying super slowly since we had the plastered added to that corner - this is also the party wall. It was turning pinkish before the heavy rain. It's looked darker since the rain, suggesting there has been water ingress.

It doesn't feel wet to touch at all though. And it is drying since and appears more pinkish in patches now.

I've also attached a photo of the outside where it's occurring. The roofer didn't want to leave without doing anything, so he added some "Crytalline" thing (I didn't catch the name though), and added a bit more lead flashing to point into the gutter more (as I wondered whether it was this too).

I just wanted to know what you all thought, just incase i'm missing something. I'm a bit annoyed about this, but I'm reading that parapet walls can be a real nuisance grrr

 

[lizziecupcakes]

 

[lizziecupcakes]

 

[Glenn586]

I’m sure that bottom sheet of lead on the right hand side has not been stitched into wall correctly. I’d be expecting it to look more like that of the left side.

 

[lizziecupcakes]

thanks @Glenn586 I thought it was that too initially. Theyve added another bit of lead underneath it (photo attached), and put it up the flashing you've referred to up against the wall more yesterday.

 

[lizziecupcakes]

 

[lizziecupcakes]

Left side is my neighbours and right side is mine

 

[lizziecupcakes]

 

[lizziecupcakes]

 

[Cubist]

I think @Glenn586 is right. Your latest pics highlight the fact that the last two lead sheets are not properly jointed with and bonded into the parapet wall. In fact the very first sheet seems only to float above the old lead-work. Sorry LCC but I think your roofer has done a pretty shabby job there.

Also worth considering is that the mortar render and pointing on your side of the parapet looks a little poor. Is the prevailing weather/driven rain commonly from that side?

 

[lizziecupcakes]

Thank you for responding!

They are coming back on Monday to fix this but now I am just totally not trusting them and won’t know it it’s okay until the next heavy rain. I am feeling so annoyed and feel like it’s stopping me from moving on with the house work

 

[lizziecupcakes]

Also worth considering is that the mortar render and pointing on your side of the parapet looks a little poor. Is the prevailing weather/driven rain commonly from that side?

@Cubist Tbh, I don’t know if the usual weather patterns/rain coming from that side. I should check - it’s a good point. I should check, although not sure how to.

I don’t think the render is in good condition either. Do you know how we can fix it? I prefer bot to remove it (it’s concrete) and I don’t think my neighbour wants that either (high costs). I thought my neighbour got a bit of re-rendeirng in her side, probably before she bought it 12 years ago because it looks like the render has been put over the top end of her flashing. Her flashing looks old too.

The roofer suggested we could use Johnson roof sealant in that corner to help, but I just have no experience with that.

 

[lizziecupcakes]

@Glenn586 @Cubist does the rest of the flashing look okay to you, eg around the chimney etc?

 

[lizziecupcakes]

Btw @Cubist , I thought i’d ask chatgpt and it said that the prevailing weather and driven rain generally come from the SW. my house faces more in a south easterly direction (including that part of the roof), so I think generally it's coming from my neighbour's side on most days. I would like to ask my neighbour if she has any leak issues, but with my neighbour though, she doesn't seem to want to do repairs on her house so if she has a leak, she would probably ignore it for quite a long time. It was a bit difficult to discuss the party wall agreement with her, but I think it was just down to her feeling a bit worried about signing things (she's elderly and I could empathise with her hesitation since we are new neighbours and she may feel vulnerable). She also lives alone.

Thankfully the plaster is drying quite well. Do you think the plasterboard and plaster is damaged? Or is likely to be damaged from constant water ingress, rather than a one off? I have a dehumidifier in there now.

 

[Cubist]

I appreciate your frustration and sadly too many of us have been stung in the past. Chin up, give em a roasting the word will soon get out that you're not someone to be taken for a ride.

Easy enough to establish typical wind directions in your area, just make a mental note each time you leave the house of which way the wind usually blows and the rain, if any, slants. Or.... you could do as you have done already.

The pointing around the bricks is more important as any gaps may allow water ingress. Both the pointing and render are easy to fix but would require the use of appropriate safety equipment for access so not likely to be cheap. If Glenns right, as I suspect he is, then your roofer should address those associated with the bond of the lead to the parapet wall.

The flashing around the chimney does not appear to have been replaced recently - the ribbon mortar pointing over the lead-work has not been replaced.

Plaster can handle getting very wet at times but plasterboard can simply fall apart or bow and distort. If theres a leak up there it needs to be addressed.

 

[lizziecupcakes]

Ah, yes, you're right regarding the ribbon mortar pointing over the lead-work has not been replaced.

Can this be fixed with just some mortar?

 

[Cubist]

Can this be fixed with just some mortar?

Yes, but if the lead-work was replaced it should have been done then.

 

[lizziecupcakes]

Just to double check, you meant this @Cubist ?

 

[lizziecupcakes]

 

[Cubist]

That mortar in the section you've highlighted appears to need re-pointing. My earlier comment concerned your question about the flashing around the chimney stack.