Leaking/Penetrating water from gutter valley & parapet wall

9 Jul 2021
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United Kingdom

I have spotted some damp spots in our bathroom. This is on a party wall with no pipe this side, so I figure this is penetrating water through the brickwork from the parapet above. And indeed, on inspection I can see some damage on the gutter valley and cracking mortar on the parapet.

1. Please have a look at the valley, this is not lead valley but something like asphalt (?) that you can walk on. What should I use to patch it up?

2. The mortar cracks along the line where this valley meet the parapet wall. Is there any treatment I can do to seal the porous structure inside (that allow rain water to seep downward)? I have heard a builder said chemical filler but not sure what type it is. And should I repoint with normal mortar or some special sealant?

3. On the other side of the parapet wall I can see it has been repaired like this before (see photo Repair). Would that work and what sort of material is that?

Thanks for your advice.


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  • Repair.JPG
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  • Mortar crack 2.JPG
    Mortar crack 2.JPG
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i thought id replied to this question, strange?
groovybug, now i see youve posted twice here and in plastering

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