Hole in chimney lead flashing - Letting in water - Fastest fix?

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Hi,

I woke up to two rooms with wet ceilings and walls today. A quick poke around in the attic and saw water was coming in around the chimney. Put my ladders up, tied them off and took the picture below.

https://images2.imgbox.com/88/b4/yolwAEWV_o.jpg

There's a hole in the lead flashing just before it tucks up into the apron around the brickwork.

What's the fastest way to fix this?

I can't wait 1 - 2 months for a roofer to come out. Ideally, I'd replace the lead with a continuous piece but that's a big job.

I have some strips of lead flashing I could cut to shape to cover the hole. Bash it into shape with a hammer. The hole is right on a bend, and at a low point, so water will sit on it.

I take it a regular propane blow torch is no good for welding the lead together (?) I see people on YT using very fine tip torches to weld lead. Seems to be a bit of an art. Too much heat and you creat another hole.

I could use lead sheet sealant under the patch. How big would the patch overlap need to be?

Thanks.
 
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As a temporary measure I’d whack some mastic on there after cleaning the area
 
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Suggest strongly, do not attempt a blow lamp repair?

Have a look @ "FLASH BAND" a sticky backed material

Clean of the lead, stick a wide strip down on to the flat of the back gutter, get it a wee bit up the vertical part of the gutter, then another piece of Flash band down and on to the already applied flash band on the flat of the gutter.

Ken.
 
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I would use flashband.

clean the lead completely, dry with a hot air gun.

paint flashband primer on.

warm up flashband on radiator so it’s pliable.

put on flashband use a seam roller to get it stuck tight

don’t just do a patch do the whole length and upstand
Fold flashband in half along length the apply to upright first working down to the corner.

use heat gun to soften the flashband and use roller again - be careful not to melt the edge too much or you will get goo all over the roller.


Yes it’s a bodge, but done well it will last for years - the key is getting completely dry surface first.
 
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Well, the patch is on.

I cut some regular lead flashing and used a roofing sealant from screwfix. Cleaned the lead back to shiny and dried it out. Hammered it flat to keep the gaps as small as possible. After all the brushing and cleaning, I found 3 holes, all on the corner.

https://images2.imgbox.com/86/78/qBJRVlH4_o.jpg

Had the option of some flashband lead sheet, but if you look at the first picture, the existing lead is anything but flat. There are big ruts all over. All it takes is a small gap and water will find a way in. The sealant I ended up using on regular sheet also filled any voids, and covers the whole patch.

Before the above patch I tried my hand at soldering. Cut a much smaller patch using 60/40 tin/lead with flux (190 deg C). This worked on a test piece (below), but it didn't work on the chimney flashing. All I managed to do was create some new holes... What I didn't factor in was the gauge of the lead sheet on the chimney which is thinner than the patch. It's also much easier to solder sat at a bench, compared to balancing on a ladder 6.5m above ground.

https://images2.imgbox.com/cf/4d/jbAVSDvp_o.jpg

Looking at this retrospectively, and given the date the leak started (11PM 25 Dec), I've come to the conclusion that the holes in the chimney flashing were created by none other than .. Father Christmas.

I shall be writing a strongly worded letter to him, advising he tread more carefully next time. :).

Thanks for the replies.
 
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