Fixing flat roof leaks in Sussex
When a flat roof starts leaking in Brighton, Hove or Worthing, property owners usually want a fast answer: can it be repaired quickly, or does it need a full replacement? I’m Jan Sagi, and after 18 years on roofs across Sussex, I’ve seen every type of flat roof failure you can imagine.
How I diagnose a flat roof leak
The first step is never guesswork. Water often travels far from the actual defect, especially on older felt systems. I check the condition of the membrane, joints, upstands, and outlets. In many cases, the real issue is poor detailing rather than a hole in the middle of the roof.
Quick fixes: when I use Acrypol
In some emergency situations, I use Acrypol. It’s a liquid waterproofing compound reinforced with glass fibres, and it can stop active leaks very quickly. It’s useful when water is coming in and we need an immediate seal.
However, I don’t personally rely on it as a long-term solution. In my experience, Acrypol typically lasts around 1–3 years, and sometimes less depending on roof movement and exposure. I always make it clear to clients that it is a temporary repair, not a structural fix.
Long-term repair: SBS torch-on felt systems
For a proper, durable repair I prefer using Tecnatorch SBS Torch-On Mineral Felt Charcoal. This is a far more robust system designed for long-term performance. When installed correctly, it should last around 20 years and provides a fully bonded, weather-resistant surface.
Unlike coatings, torch-on felt becomes part of the roof structure. That’s why I recommend it for most flat roof repairs where the substrate is still sound enough to justify a permanent solution.
Silicones and quick sealants
We live in a time where silicone products are used everywhere, but I’m cautious with them on roofs. On some older structures where the roof is already at the end of its life, silicone patches can be a reasonable short-term measure. But on roofs that are meant to continue performing, they rarely provide a reliable long-term fix.
Where it makes sense, I prefer mechanical or lead-based detailing rather than relying on surface sealants alone.
My repair process on site
When I attend a leak, I start with a full inspection and moisture assessment. If it’s urgent, I may stabilise the issue immediately before planning a permanent repair. You can request an urgent leak assessment if water is actively entering the property.
Once the cause is identified, I’ll recommend either a targeted repair or a full system replacement using high-performance materials. For general cases, you can also view my flat roof repair service for more structured solutions.
Repair or replacement?
Not every leaking roof should be patched. If the insulation is saturated, the decking is rotten, or the felt system is already beyond its service life, repairs will only delay the inevitable. In those cases, I advise full replacement to avoid repeated costs.
Final thoughts
Fixing a flat roof properly is about choosing the right material for the condition of the roof, not just the quickest option. Acrypol has its place in emergencies, but for long-term peace of mind I always aim for a structural, durable repair.
If you’re unsure what your roof needs, I provide an instant online calculator on my website so you can get a rough price estimate in about 30 seconds before deciding on a site visit.