Common flat roof problems and how to solve them

  • 9 years ago
  • DIY

While flat roofs are often made from simpler materials than pitched roofs and tend to be cheaper to construct, they can be prone to leaks and other common problems. Roof damage can be expensive, but if you know what issues are likely to occur you can work on preventing them – or if they’ve already happened, can fix them in the best way possible – so here are some handy tips.


Flat roofs work well in warm countries with limited rainfall, but if they’re exposed to a lot of precipitation they can start to leak and need to be repaired before the problem gets worse. Thankfully companies like provide a wealth of emergency repair paints as well as waterproof flat roof paints which can provide up to 25 years protection for felt, concrete, timber, asbestos and more. This is the kind of specialist material you’ll need to complete such a job properly and efficiently.

What’s more, you can get rid of ponding water by adding roof drains or automatic siphons for ponds in the centre of the roof. These should be kept clear of debris at all times as a clogged drain will still cause water to pond causing a dead weight that’s too heavy for the roof to handle, leading to a possible collapse. Maintenance is key and the quicker the water is removed from the roof the less chance there is that a problem will occur.

Flashing issues

Flashing is a material – usually aluminium or galvanised steel – that’s used over joints in roof construction to prevent water from seeping in and causing leaks. This can become damaged due to weathering and oxidisation and might need to be replaced or resealed with plastic cement, mesh and a small mason’s trowel. There are many how-to guides online, but if you don’t feel confident, always get a professional to do the job for you. Loose flashing can also cause leaks, so it’s important to keep an eye on the condition of your roof.

Roof blisters

Roof blisters or creases might not leak instantly but over time they can become points of weakness that eventually provide a route for water to seep through. Once this occurs they will only get worse, so cover with plastic cement and mesh or use special roof coatings and paints that can fix leaks and extend the life of a flat roof. Roof coatings also prevent degradation by the sun and offer a seamless, watertight membrane.

Flat roof problems do occur and while many are relatively simple to fix they can take time and money to solve properly. With this in mind, always try to take preventative measures and keep your roof in good condition.

Compare listings