Lead bay roof leaking

[Andy Pandy]

My bay roof leaks when there's heavy rain. The problem seems to be hairline cracks in the mortar just above where the lead enters the mortar. I've been out today with a hosepipe and gave the lead (not the wall) a thorough soaking and no water came through. I then soaked sections of the wall where the lead enters the mortar and think I've identified the section of wall where the water is getting in.

My question is - how to fix the problem. Does the mortar need to raked out and repointed, or can I just use some sort of sealant over the cracks? If so, what's the best sealant to use?

TIA

-- Andy

[stuart noble]

Re-pointing with a pva mortar should improve matters, but you'll need to rake out to a depth of at least an inch. If the bricks themselves are letting water you may have to render. I don't think any sealer/surface coating is likely to be effective for long.

[Pete C]

Hi,

Would PVA do it? It should soak into the mortar if dry and looks fairly transparent.

cheers, Pete.