Replacing (chimney) flashing.

[Jethro_uk]

AS luck would have it, our roof sprung a leak a few weeks ago. A panicked run up the roof suggests it's the flashing - the bottomost strip - which runs up the roof along the chimney. For now, a heavy duty plastic sheet has been fixed under the offending run, and seems to be doing the trick.

Leaving aside the fact that it was allegedly replaced (with the rest of the roof) 4 years ago, initial googling suggests it has to be replaced.

I have some concerns about having to shape new flashing - not really in my skill box. However, my bigger worry is mortaring it in. Especially in the winter. And even before that, raking out the old mortar.

All of this being the case, I notice there are quite a few lead flashing alternatives ... certainly here :

alternative.html

What's the groupthink on such things ?

[Roger Hayter]

If the firm that did the roof four years ago still exist I would think they would be sufficiently embarassed to at least have a look and see whether they thought their work inadequate or there was some other cause.

Wouldn't you still have to mortar in the lead substitue? Received wisdom is that the subsitutes don't last as long, though they should last more than four years!

[Dave Plowman (News)]

Working with lead in incredibly satisfying and not nearly as difficult as you might think if you've not done it. Properly done it will outlive all of us.

[Robin]

I found Lead Mate easier - and neater than my execrable pointing. (You can use gaffer tape to keep the edges neat!) Can be used applied down to 5 Celsius.

Other brands are available.

[Jethro_uk]

One to look at ...

[Jethro_uk]

I will bear than in mind. The take home phrase being "properly done" ...

[Bill Wright]

From what I saw in my 45 years as an aerial installer lead is best. I saw plenty of failed lead substitutes. I retired four years ago though so there might be better things now. I had to replace the lead flashing round my own chimney and found it quite easy. As for fixing the lead into the mortar joint:

-- chase out quite deep

-- make wedges from lead and hammer them into the joint at intervals to hold the lead sheet

-- use a fairly stiff mortar mix with lots of cement.

-- use a woodworkers mallet to shape the lead, then a normal hammer to mould it to the tiles.

Bill

[Tim Lamb]

Just so!

[Dave Plowman (News)]

When my main roof was being done some 30 years ago, I got the roofers to provide the materials to do the roof on my outside loo. Including the lead to do the stepped flashing. I had watched them do the main roof, and found it not that difficult. Since then added lead flashing where the conservatory leans too. And discovered that lime mortar is better for pointing it. Had to repair some of that the roofers did with ordinary mortar.

[Dave Plowman (News)]

Yup. I treated myself to a 'proper' lead dressing tool. Made from a semi hard plastic. Local BM sold them.

[alan_m]

I've had to replace a small amount of pointing where the roofers attempt failed. I suspect that when they did it it dried too quickly - it was initially done on a hot Summer's day. I raked out the old, washed out the gap to clear it of debris and to dampen the surrounding brick and used cement based mortar - but waited until the late afternoon when the wall was in shade.

[Jethro_uk]

Which echoes the question I am thinking about timing, winter etc ?

[Roger Hayter]

You could use quick setting cement in the mortar. Or, as someone said above, they do tubes of very sticky lead-coloured sealant especially for the job, and it seems to work very well - though I have no idea how long-lasting it is.

[Jethro_uk]

That's the stuff they used in the Uniflex video ... the claimed life is

25 years.

[Huge]

Whatever you do, don't leave your rubber mallet on the roof, like I did ...

[damduck-egg]

I can remember by Dads delight at finding his slate ripper resting by a chimney stack when he was going to repair on a customers roof sometime in the early 70's . When did you leave it there ? I asked thinking it may have been at the beginning of the job, " about 1953 when I replaced some slates" he replied . "i knew it would turn up eventually".

G.Harman

[Huge]

I'd already replaced my rubber mallet. The old one was only up there a couple of years.

[Jethro_uk]

Thanks for reminding me ... I have a rubber mallet somewhere.

[Andy Burns]

I have two, but my neighbour's daughter-in-law borrowed one (I wouldn't have lent the non-marring one if I thought it wasn't coming back).

[Dave Plowman (News)]

How long do they warrant it for?

Bit like car batteries.

'Our batteries are designed to last far longer than others, hence the higher price'

What's the warranty?

'Three years'