Flat Roofing in Norwich

Expert Flat Roofing
in Norwich

Why Flat Roofs Fail - and How to Spot Trouble Early

A flat roof that is performing well is easy to forget about. The problem is that the signs of failure are often subtle right up until water is coming through your ceiling. Knowing what to look for means you can deal with an issue while it is still minor and relatively inexpensive to fix.

Flat roofs on extensions, garages and outbuildings are the most common casualties. They take direct rainfall, standing water and temperature swings all year round. When the membrane, felt or finish starts to break down, the process can move quickly - especially once water finds a way in.

The Warning Signs You Should Not Ignore

The most obvious sign is water inside the building. Damp patches on a ceiling below a flat roof, or brown staining around the edges of a room, usually mean water has been getting in for some time. By the time you see it inside, the roof deck and insulation may already be wet through.

On the roof surface itself, look for these problems:

• Blistering or bubbling - pockets of trapped moisture or air beneath the membrane surface. They tend to split open under foot traffic or in hot weather, letting water in.
• Cracking or crazing - especially on older felt roofs. UV light breaks down the surface over time, causing the top layer to crack. Once the surface is open, water gets into the layers below.
• Ponding water - flat roofs should have a slight fall (typically at least 1:80) to drain water off the surface. If water is sitting for more than 48 hours after rain, the drainage or the fall is wrong. Standing water accelerates deterioration of any roofing material.
• Lifted or open seams and laps - where sheets of felt or membrane overlap, those joints are the most vulnerable points. If they lift or open up, water tracks straight through.
• Damaged or missing upstands and flashings - where the flat roof meets a wall, chimney or parapet, a flashing seals the junction. Failed lead or mortar at these points is a very common source of leaks that can be mistaken for a failed roof surface.
• Sagging or soft spots - press gently on the roof surface near the edge. If it gives more than it should, the deck beneath may be rotten. Decking that has been wet for a long time loses its structural strength and cannot hold fixings properly.

What Actually Causes a Flat Roof to Fail

Poor installation is the single biggest cause of premature flat roof failure. A membrane laid without the correct preparation, wrong adhesive, insufficient fall or badly dressed flashings will fail far earlier than it should. A correctly installed EPDM rubber roof, for example, can last well over twenty years.

Age is a factor with traditional mineral felt. Three-layer felt systems have a realistic working life of around ten to fifteen years. When they reach the end of that life, patching repeatedly costs more in the long run than a full replacement with a more durable system.

Poor drainage causes problems that compound over time. Water that sits on a roof puts weight on the deck and keeps the surface wet, which accelerates the breakdown of any membrane material. A blocked outlet or a low spot in the decking can turn a good roof into a failing one over a few seasons.

Thermal movement is another factor. Flat roof materials expand in summer heat and contract in winter cold. If the system is not designed and installed to accommodate this movement - particularly at seams, upstands and outlets - it will eventually pull apart at those points.

Should You Repair or Replace?

A single small split or a lifted lap on an otherwise sound roof that is less than ten years old can often be repaired effectively. However, if the roof is old felt showing widespread cracking, if the deck is soft in more than one area, or if you have had repeated leaks in different places, repair after repair is rarely the right answer. A full replacement with EPDM rubber or a modern felt system will cost more upfront but removes the ongoing problem.

Ask any roofer who surveys your roof to tell you the condition of the deck, not just the surface. Replacing a membrane over a soft or wet deck is wasted money - the deck has to be replaced or dried out first.

Flat Roofing Systems We Install

We install EPDM rubber and felt flat roofing systems on extensions, garages and outbuildings across Norwich and the surrounding area. EPDM is a single-ply rubber membrane that is highly resistant to UV and temperature movement - it is a popular choice for a long-lasting, low-maintenance result. Mineral felt systems are a cost-effective option where budget is a priority, provided the installation is done properly with correct laps and a quality top layer.

Every installation includes correct attention to the falls, outlets and upstands - the details that most often cause problems when they are rushed or skipped.

Covering Norwich and Nearby

We work across Norwich and the wider area, as well as nearby towns and villages throughout North Norfolk including Stalham and North Walsham. If you are not sure whether we cover your postcode, call us and we will tell you directly.

Get a Proper Assessment Before You Spend a Penny

If you have noticed any of the warning signs above, call us to arrange a roof survey in Norwich. We will check the surface, the deck condition, the falls and the flashings and give you an honest picture of what is going on and what it will take to fix it properly. Call North Walsham Roofers to book your flat roof survey.