Roofing

Conflicting advice on leaking roof valley - waterproof sealer or replace mortar?

Anonymous user 03/03/2024 - 3.10 PM

I have a small leak that is coming through the felt that sits under the top end of the valley. I've had 2 roofers in who have said different things. First said the fitting of the valley has been done poorly when house was built (20 years ago), but could be fixed with a waterproofing sealer (liquid rubber?). Surely if the issue has been there for 20 years the I'd have had a leak earlier, or maybe the felt has protected me? To do valley on both sides of the pitch - £220.00. Second guy said the mortar holding the tiles in place along the valley needs replacing (previous guy said mortar was fine), as all the tiles are loose & not fixed in place - £780 to dig out & replace mortar. He didn't go on the roof, just up the ladder. So, should the tiles be fixed, or do they simply need to rest on the mortar? And is it possible to seal the valley & its surround to waterproof it? Any help greatly appreciated as I'm struggling to get another builder out to quote. ----- Not sure how to reply here, so just adding to my post. Thanks to Stronghold construction for your reply. No, neither guys took photos, despite having a camera! Managed to get a third firm out today, who say the mortar will need replacing in time, but it's not the cause of the leak. They feel the problem is at the apex of the valley - water is possibly pooling in a small mortar area (photos taken!!), so putting in a lead saddle which cannot currently be seen, & mortaring. It certainly seems the most plausible reason, bearing in mind the leak comes through the felt towards the top end of the valley. Thanks again.