Got Problems With Your Lead Flashing? Let’s Talk.
It’s one of the most common calls I get across Brighton and Worthing. You’ve spotted a damp patch on your ceiling, usually right by the chimney stack or where a wall meets the roof. Nine times out of ten, the culprit is failed lead flashing. Before you panic, let me walk you through what’s happening and what you can (and can’t) do about it.
First off, what even is lead flashing and why does it fail?
Think of lead flashing as the waterproof seal in the awkward corners of your roof. It’s a sheet of lead that’s expertly shaped to bridge the gap between, say, your roof tiles and a brick chimney. It stops rainwater from sneaking into those joints. It’s brilliant stuff and lasts for decades, which is why it’s so common on pitched roofs across Hove.
So why does it fail? Over many years, the constant heating and cooling from the sun makes the lead expand and contract. Eventually, it becomes brittle and can split or tear. Sometimes, it’s just been fitted badly in the first place, with the wrong fixings or without enough room for movement.
Can I just paint it with bitumen or a waterproof paint?
Honestly? Please don’t. This is the number one mistake I see. Painting over a split in your lead flashing is like putting a sticking plaster on a broken leg. The lead underneath will continue to expand and contract, and that paint will crack and peel within a year, leaving you right back where you started, but with a messier problem.
What’s a realistic DIY fix for a small split?
Look, I get it. You’ve got a drip, and you want it stopped now. If you’re comfortable on a ladder and the split is small and accessible, you can try a temporary patch. You can buy a tube of lead sealant or a roll of self-adhesive flashing tape (like Flashband) from a hardware store.
My honest advice for a temporary fix:
- Clean the area thoroughly: Use a wire brush to get rid of any moss, dirt, and loose bits. The surface must be clean and bone dry for anything to stick.
- Apply the sealant or tape: If using sealant, push it deep into the split. If using tape, cut a patch that’s much bigger than the hole and press it down firmly, making sure there are no air bubbles.
Here’s the hard truth: This is a short-term band-aid. It might get you through a rainy weekend, but it is not a permanent repair. The movement of the lead will eventually break that seal, and you’ll have an urgent roof leak on your hands again.
So, when is it time to call a professional?
You need to call a roofer if:
- The split is larger than a couple of inches.
- The lead has lifted away from the wall or has large, sagging sections.
- You have multiple splits all over the place.
- You’re not 100% confident working at height. It’s not worth the risk.
- Your ‘DIY fix’ has failed and the leak is back.
Often, a leak you think is the flashing could be from something else entirely, like cracked tiles or even problems with your guttering. I can spot the real source of the problem straight away. If you’re unsure, just book a free roof inspection with me and I’ll tell you exactly what’s going on up there.
How do I fix lead flashing properly?
When I turn up to a job, I don’t just slap sealant on it. A proper, permanent professional lead flashing repair involves either welding a new piece of lead over the split (lead welding) or, more often, cutting out the failed section entirely and replacing it with new code 4 or 5 lead, correctly shaped and fixed into the mortar joint.
This is a skilled job. It has to be done right to allow for thermal movement, or it’ll just fail again in a few years. When I do it, it’s fixed for good. I provide a fixed-price quote so you know exactly what it’ll cost, and you can even track my progress through my client portal with daily photo logs. No mystery, just a proper job done right.