Leaking flashing

29 May 2020
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United Kingdom

So basically i have had some awful leaks during the storms and I have had visits from every tradesman you can imagine including 3 roofers who all suggest putting a lead flashing over the top of the rubber upstand.

I know this work is needed but due to personal issues i am hoping to survive another winter without any leaks so have literally filled the mortar / upstand joint with sealant and then went over the entire mortar bead with more sealant.

As you can tell from the attached photos i am terrible at sealing and hate doing it! :D The picture only shows a small section but i have done this across the entire upstand. I have tested it with plenty of water and no leaks so far (i previously managed to make it leak pouring water over the upstand) and seeing as it will probably need ripping out soon i don't really care what it looks like.

I know its a total bodge job but it only ever leaked during heavy rain and very strong winds so i am hoping this will keep it at bay.

Any thoughts?

Many thanks.


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If it keeps the water out and saves you money that you probably don't have then crack on. Silicon won't last forever in that position, if you end up having more leaks then rake out the mortar (shouldn't be hard by the looks of it, there's only a skin in there) and put Leadmate in the gap instead ( it'll last a lot longer)
thanks for the reply

its not a long term solution but more of a band aid for now. do you think a lead flashing is needed or should the gap of been filled with leadmate in the first place?

ive attached another few pics


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Pointing narrow beds with mortar is always tricky. Leadmate is much more expensive but much easier to get a decent looking long lasting seal. The bits of the cover flashing in the pic look OK, long as they're set into the chase by 25mm or so then they'll be fine.
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before i applied the sealant, the mortar had definitely eroded away in some places. It also seems to have no grab on the cover flashing which makes me think it should of been sealant all along? so my theory was rather that removing all the mortar and possibly making the leak happen more often (seems to only be during heavy rain and wind) i would go straight over the top of the mortar just to seal whats there short term and then when i can get the lead flashing done or at the bare minimum get a roofer to rake it out and fill with leadmate.

Ive had conflicting views by roofers....some say a lead flashing is needed and others say the seal needs redoing. I have noticed some slight movement in the flashing when its pushed which im assuming is where the mortar no longer holds it... also around the door entrance its not all the way around the brick?

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