Flat roof problems are a source of continuous nuisance for homeowners across the UK, with old fashioned installation practices that cannot get through at our present and ever-unpredictable weather conditions.

Thankfully, we now have modern materials that allow roofing professionals to provide 50 or more years guaranteed on flat roofs and are insured across the UK. The three most common materials available are the following:

  1. EPDM Rubber Flat Roof
  2. Liquid Rubber Flat Roof
  3. Fiberglass Flat Roof

All of the above are excellent roofing materials to use, and if applied properly, they will last almost a lifetime. They can be cheaper than the traditional roof due to the simplicity of the installation procedure.

Though flat roof system have many benefits over time, they can also sustain damages and problems, which, if left unchecked, can lead to much more significant issues. Here are some of the most common flat roof problems and how to deal with them:

Ponding Water

Flat roofs do not drain very well compared to pitched roofs, which can lead to ponding water. Ponding water is defined as a water puddle formed on a roof for 48 hours or more. The problem only develops when the water remains there for a while. This can generate stress on the flat roof’s membrane and can begin to wear it down.

Also, ponding water can lead to leaking if the stress on the membrane is too much, which will allow moisture into the roof.


Being proactive and keeping your flat roof well maintained is the best way to stop ponding water. Having your gutter and drains maintained is essential. Any form of blockages should be addressed as quickly as possible to prevent ponding water.

Furthermore, having professionals install your flat roof can reduce any potential for ponding water to form.

Ponding Water
Cracks in Flat Roof


With age, the flexible materials that compose the waterproof layers of your flat roof can crack, wear away or rip, due to water, debris or long term exposure to the sun.

The cracking will eventually develop further if left unnoticed, leading to water getting into the roofing and cause leaking and more damage.


Applying a new coating to your flat roof can fix cracks. Thoroughly clean the flat roof, removing all unwanted debris. Then use a primer. Once the primer has dried, apply the new coating.


Blistering happens on your flat roof when small pockets of air or moisture get caught under the membrane or between the layers of the membrane. The sun can worsen this, which causes the pockets of air or moisture to expand, thus stretching the membrane.


As long as the blisters stay intact, you don’t need to worry too much. If they do pop, you can either replace or repair them.

To repair your flat roof’s blisters, cut the blistered part up to the point that it is joined tightly to the roof. Then you can reapply the new membrane material, stretching it to at least six inches over the edge of the blister to prevent future leakage.

Blistering in Flat Roofs


Temperature changes can cause the flat roof’s materials to expand and contract, which is normal. Still, you must observe your roof for signs of this, as continuous expansion and contraction can weaken the flat roof and cause leaks.

Additionally, this movement can also happen on your flashing, resulting in it pulling away from the edges of your roof. This can potentially leave room for leakage.


Make sure you use high-quality roofing materials and flashing and that they are professionally installed. If you see your flashing pulling away from the edges of your roof, it’s best to call professional roof services and fully replace the flashing.