What’s the Real Story with Roofing Guarantees?

You see it on every van and every quote: “10-Year Guarantee!” “25-Year Guarantee!” It sounds great, but let me be blunt: a guarantee is only as good as the person who gives it to you. I’ve spent 18 years fixing roofs in Brighton, Hove, and Worthing, and a lot of those fixes were on roofs that were still supposedly ‘under guarantee’ from another company that’s suddenly impossible to get on the phone.

A piece of paper doesn’t keep the rain out. Good workmanship does. So let’s break down what a roofing guarantee actually means, so you don’t get caught out.

The Two Guarantees You Actually Get (And Why One Matters More)

When you get a new roof, you’re not getting one guarantee. You’re getting two, and you need to know the difference.

1. The Manufacturer’s Guarantee (The Paper Promise)

This is a guarantee on the physical materials – the felt, the EPDM rubber, the GRP fibreglass, the tiles themselves. The company that made the product guarantees it won’t fail due to a manufacturing defect. This can be 10, 20, even 30 years.

Here’s the hard truth: it’s incredibly rare for a modern, quality roofing material to fail on its own. When it does, manufacturers can be experts at finding a reason to blame the installation, not their product. They might say the decking wasn’t right, the ventilation was poor, or it was installed in the wrong weather. In my experience, relying on a manufacturer’s guarantee alone is a risky game.

2. The Roofer’s Workmanship Guarantee (This is The One to Care About)

This is my promise to you. This is the guarantee that matters. At least 99% of roof leaks on new or recently repaired roofs are due to poor workmanship, not faulty materials. It’s about how the seams are sealed, how the lead flashing is dressed, and how the details around vents and skylights are handled. This is where experience counts.

My workmanship guarantee covers you against leaks or failures caused by how I installed your roof. If it fails because of something I did, I come back and fix it. No arguments, no excuses. It’s my reputation on the line with every job I do in Sussex.

“So, what does your 20-year flat roof guarantee actually cover, Jan?”

This is a question I get all the time, and I respect it. When I install a new GRP fibreglass roof, for example, it comes with a long guarantee. That guarantee means that if the roof I installed leaks due to a defect in my workmanship within that period, the repair is on me.

It covers the integrity of the roof system I installed. If you want to see the kind of systems I stand behind, you can read about my flat roof services here.

What it doesn’t cover is damage from other sources. If another tradesperson drills a hole in it to fit a satellite dish, or if a storm drops a tile from your neighbour’s roof onto it, that’s not a workmanship issue. It sounds obvious, but you’d be surprised.

What Can Void Your Roofing Guarantee?

A guarantee isn’t a blank cheque for the roof’s entire life. You have to look after it. Here are a few things that can instantly void a workmanship guarantee:

  • Unauthorised Alterations: Fitting a skylight, solar panels, or a satellite dish by someone else without consulting the original installer.
  • DIY ‘Fixes’: Slapping a bit of sealant on a problem you see. This can often make the problem worse and masks the true source of the issue.
  • Pressure Washing: Never, ever pressure wash your roof. You can lift seals, damage membranes, and force water where it shouldn’t go.
  • Neglect: Letting gutters get completely blocked can cause water to back up under tiles or over flashings, causing issues that aren’t related to the installation quality.

My Guarantee to You

My approach is simple. I provide a fixed-price quote with no hidden extras. You get a client portal where you can see daily photo updates of my work. You see exactly what’s being done and how it’s being done.

The guarantee I provide is based on that transparency and the quality of my work. Whether it’s a full pitched roof replacement or a detailed repair to some leaking lead flashing, my name is on it. If you have an active problem right now, the first step is always a proper diagnosis; my emergency leak repair service is designed to find the source and fix it properly.

Before you commit to any work, the most important step is understanding the true condition of your roof. If you’re in the Brighton area, I suggest you book a free, honest roof inspection with me. I’ll get up there, take pictures, and tell you exactly what you’re dealing with – no obligation, no sales pitch, just straight facts.