Lead valley repair with flashband

Jul 12, 2020 2 Replies

After the rain last week, a piece of soffit fell off, and on inspection the lead valley appears to be leaking. No damage that I can find to actual str uctural timber, just the piece of wood that the soffit was nailed to. I've cleaned the wood out, and applied wet rot hardener.


1930s house, slate roof, plenty of slipped slates, but none that would have any bearing on this. Found a piece of flashband (I think, and there's no r eason to suppose the previous owner did anything fancy like welding a plate on) over the lap between two sections of valley. I'm looking for bodge it again. I don't need a repair that will last for more than two years, possib ly even just one winter (quite likely we will do a loft conversion in the n ear future, and we will definitely redo the whole roof at that time. Is the simplest option to replace the flashband? How would I go about getting it off? I think I'll be happy working with a roof ladder and a belay over the ridge from my climbing gear, though I might just hire a tower.

he lead valley appears to be leaking. No damage that I can find to actual s tructural timber, just the piece of wood that the soffit was nailed to. I'v e cleaned the wood out, and applied wet rot hardener.

ve any bearing on this. Found a piece of flashband (I think, and there's no reason to suppose the previous owner did anything fancy like welding a pla te on) over the lap between two sections of valley. I'm looking for bodge i t again. I don't need a repair that will last for more than two years, poss ibly even just one winter (quite likely we will do a loft conversion in the near future, and we will definitely redo the whole roof at that time. Is t he simplest option to replace the flashband? How would I go about getting i t off? I think I'll be happy working with a roof ladder and a belay over th e ridge from my climbing gear, though I might just hire a tower.

To remove flashband. Heat it up with an electric heat gun to soften the bla ck stuff.

A blowlamp would be a bit dodgy as it'll probably have bitumous roof felt u nder the slates. (check this from inside.)

Use a hot air gun to soften the mastic under it and use a wallpaper stripping tool or similar to scrape it off. Clean the lead with petrol or similar solvent and lightly abrade it, to remove surface oxides. If the sun makes the lead warm to the touch, you don't need to do anything more. Otherwise gently warming the underside of the flashband will help it adhere. Once in place, press it down firmly with a wallpaper seam roller.

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